JPH11260596A - Plasma processing device and plasma processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control the constituents and capacity of activating seeds and thereby carry out highly selective etching, and high-precision and high-speed etching by controlling electron energy and electron density in plasma by means of electromagnetic waves. SOLUTION: A process gas in a processing chamber 9 is transformed to plasma by the use of a capacitive coupling discharge means by supplying power from a power supply 1 to a parallel, flat electrode 2, and thereby various activating seeds are produced, and an electric field 14 is induced near a side wall part 6 by an electromagnetic wave radiating antenna 11, and the condition of the wall surface of the side wall part 6 is controlled by adjusting a power supply 12. The diffused plasma also infiltrate into the gaps of parallel, flat electrode plates 2, 3, so that radical composition can be controlled. In addition, by generating magnetic lines of force 15 by the use of a magnetic field generating means 13 and thereby developing electron cyclotron resonance by the electric field 14 of the antenna 11 and the magnetic lines of force 15, plasma is effectively generated, and thus, the performance of minute processing can be optimized by regulating the intensity of the magnetic field 15 and thereby adjusting the radical ingredient ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing apparatus provided with a plasma generating means, and more particularly to a plasma etching method and a fine structure suitable for forming a fine pattern of a semiconductor device or a liquid crystal display element and uniformly processing a large-diameter substrate. The present invention relates to a plasma processing apparatus and a plasma processing method suitable for forming a thin film, such as plasma CVD and plasma polymerization.

[0002]

2. Description of the Related Art In a plasma processing apparatus for processing semiconductor elements and liquid crystal display elements using plasma, control of active species which influence processing performance, energy of ions incident on a processing substrate, ion directionality, and uniformity of plasma processing. , And the productivity of plasma processing is required.

Regarding the control of active species, see, for example,
There is a parallel plate electrode type as disclosed in Japanese Patent Application Laid-Open No. 7-131374, and a conventional example of the parallel plate electrode type plasma processing apparatus is shown in FIG.

In the apparatus shown in FIG. 17, a processing chamber 9 surrounded by a cylindrical side wall portion 6, an insulating portion 5, and a disk-shaped electrode 2 is provided.
Are maintained in a vacuum state by a gas exhaust unit (not shown), and a gas supply unit 7 supplies a processing gas to the processing chamber through the electrode 2 having a function of a gas introduction path. Normally, the side wall portion 6 is grounded, and is insulated from the electrode 2 by the insulating portion 5. The electrode 2 and the support 3 constitute a parallel plate electrode, and when the power source 1 applies power between the parallel plate electrodes, the processing gas inside the processing chamber 9 is turned into plasma.

In the lower part of the processing chamber, a wafer 4 to be processed is placed on the support 3. The wafer 4 is generated by plasma generated in the processing chamber 9 and activated species (radicals) in the processing gas activated by the plasma. Fine processing is performed. At this time, the density of the plasma and the temperature of the electrons in the plasma change depending on the input power applied by the power supply 1, the pressure in the processing chamber 9, the width of the gap between the electrode 2 and the support 3, and the like. In other words, the state of the amount and ratio of some active species that affects the performance of microfabrication changes.

As for the control of ion energy, there is a method as disclosed in Japanese Patent Application Laid-Open No. 4-239128.

In this method, a divergent magnetic field perpendicular to these electrodes is provided on a parallel plate electrode, thereby controlling the self-bias voltage and controlling the energy of ions incident on the substrate independently of the output of a high frequency power supply for generating plasma. This enables independent control by a magnetic field and performs high-precision etching processing without causing damage.

As a method for increasing the directionality of ions and not lowering the processing speed, there is a method disclosed in Japanese Patent Application Laid-Open No. 8-195379.

This is to generate plasma with both capacitive coupling and inductive coupling, thereby generating high-density plasma at low pressure and realizing plasma processing excellent in controllability of plasma density distribution. .

As a plasma processing apparatus for controlling the uniformity of the plasma processing, there is an apparatus disclosed in JP-A-61-283127.

In this apparatus, the electrode to which high-frequency power is applied is divided into a plurality of electrodes, and the power applied to each electrode is controlled independently to improve the uniformity.

A major problem in increasing the productivity is that films such as etching and plasma CVD form a film on the inner wall surface of the processing chamber, which are separated and lead to generation of dust. This means that the ratio of non-defective products in the devices manufactured or in the liquid crystal display device, that is, the product yield is reduced. In addition, there is a problem that the processing characteristics are changed while the production is continued, and the product yield is reduced.

When dust is generated, the deposition film formed by plasma processing on the inner wall of the processing chamber repeats temperature fluctuations due to a change in heat input from the plasma. As a result, stress is generated in the deposition film and the film becomes thicker. Becomes greater than the adhesive force, peeling of the film starts, and dust is generated.

In order to remove the deposit film formed on the inner wall surface, a plasma processing apparatus for increasing the energy of ions incident on the surface on which these deposit films are formed to increase the removal rate of the deposit film is disclosed in Japanese Patent Laid-Open No. 8-330282. No. 6,086,045.

Further, there is disclosed a method of converting a deposition film on the inner wall surface into a volatile substance and discharging the substance by a vacuum exhaust system.
A method is known in which a non-gaseous material is placed in a processing chamber, and the material reacts with the plasma to generate reactive species, which reacts with the depo film to convert the depo film into a volatile substance and clean it. It is disclosed in Japanese Unexamined Patent Publication No. Hei 7-153751.

As methods for stabilizing the processing characteristics of the plasma processing, JP-A-6-188220 and JP-A-61-188220 disclose the method.
No. 8927 discloses a method for controlling the inner wall surface of a plasma processing chamber to a constant temperature, a device provided with electrodes cooled by a fluid having a parallel structure, and the like.

[0017]

With the increase in the degree of integration of semiconductor elements and the increase in the diameter of production substrates, the selectivity with respect to the underlying material,
There has been a further need for higher performance of processing shapes, uniform processing of large-diameter substrates, and reduction of dust generation.

1) Etching by plasma, CV
One of the factors that largely affects the processing characteristics such as the selectivity of D processing and the like, the processing shape, and the film quality is active species generated by electron collision in plasma. The amount of generated active species and the generated active species are determined by the energy status of electrons in the plasma.

The energy state of the electrons in the plasma is determined by the collision frequency depending on the processing pressure, the extinction ratio due to the diffusion of the electrons in the plasma, and the like. The energy state of the electrons in the plasma becomes a statistical distribution due to collisions with neutral molecules, ions, etc., and it is difficult to control the distribution other than changing the statistical distribution by changing the collision frequency like pressure. there were. Therefore, in order to control the state of the electron energy, a method of controlling the processing pressure has conventionally been adopted. However, in the method of controlling the processing pressure, it is difficult to achieve a balance between the fine workability of the etching process and the selectivity, and it is difficult to achieve a balance between the film forming speed, the film quality, and the performance of covering the element surface by the plasma CVD.

One of the objects of the present invention is to provide a means for controlling electron energy in a plasma independent of a plasma generating means and an ion energy controlling means separately from the conventional process conditions such as pressure, and It is an object of the present invention to provide a plasma processing apparatus capable of controlling a quantity of active species, having a high selectivity, and performing fine processing.

2) Regarding the uniformity of the plasma treatment, it is necessary to achieve compatibility with active species control, ion energy control, and low-pressure high-density plasma generation technology.

Further, as the diameter of the processing substrate increases, the processing gas flows from the central portion of the substrate to the outer peripheral portion in the etching process or the CVD process. It is becoming difficult to perform uniform processing over the entire surface of the substrate. Therefore, in order to solve these problems, it is necessary to cancel a factor that makes it impossible to make the distribution uniform by another etching characteristic control factor. One control factor for this is to make the plasma distribution independent of other process conditions such as plasma density and pressure,
It is necessary that the unevenness distribution of the plasma can be adjusted for each process condition.

One of the objects of the present invention is to provide a uniformity control mechanism capable of controlling plasma uniformity with active species control, ion energy control, low-pressure high-density plasma generation, and independently of other process conditions. A plasma processing apparatus having
And a plasma processing method.

3) In order to reduce dust generation, it has been considered as a prior art to remove a deposit film adhering to the inner surface of the processing chamber. However, a method of evaporating and exhausting the deposit film is to vaporize the deposit film. There is a problem that it takes time and the productivity is reduced. In addition, the surface after removing the deposition film is exposed to radicals and ions in the plasma, so that the surface deteriorates, and the reaction on the wall surface changes, thereby affecting the plasma processing characteristics and the like.

In addition, surfaces having different states, such as a surface to which high-frequency power is applied and a grounded surface, coexist on the wall surface of the plasma processing chamber, and it is necessary to reduce dust generation corresponding to these surfaces.

An object of the present invention is to provide a plasma processing apparatus which can be operated for a long time without generating dust and which does not reduce productivity.

[0027]

According to the present invention, the above object has been attained by the following means.

1) A means for generating plasma by capacitively-coupled discharge, a means for radiating electromagnetic waves into the plasma, so that electrons in the plasma generated by the capacitively-coupled discharge are given energy by the electromagnetic waves, and the energy and electron density of the electrons are reduced. It is a means for controlling and controlling the component ratio of the active species and the amount of the active species.

An antenna for inputting an electromagnetic wave and a parallel plate electrode in a processing chamber, and a magnetic field that allows the input electromagnetic wave to travel in plasma are provided, and the plasma generation region of this antenna overlaps the plasma generation region of the parallel plate electrode. The energy and electron density of electrons are controlled by mixing two types of plasmas, plasma generated by parallel plate electrodes and plasma generated by electromagnetic waves input from an antenna. The energy of the electrons can be controlled by the radiation of the electromagnetic waves from the antenna, and by changing the ratio of the power supplied to the capacitively coupled discharge and the radiation of the electromagnetic waves from the antenna,
The state of electron energy in plasma can be changed, and the amount of active species and active species can be controlled.

Further, the magnetic field strength of the magnetic field is made variable with respect to the frequency of the radiated electromagnetic wave, including conditions under which electron cyclotron resonance occurs, whereby the energy level given to the electrons in the plasma is changed. Control.

2) Regarding plasma uniformity control, two or more antennas for radiating electromagnetic waves in the plasma are provided.
The distribution of the plasma is controlled by means for controlling the electromagnetic waves radiated from each antenna.

The fact that the electron density can be controlled by radiating the electromagnetic wave into the plasma is as described in the section on the control of generation of active species.

As antenna means for radiating electromagnetic waves, electrodes for capacitively-coupled discharge are divided into a plurality of parts, and a high-frequency voltage is generated between the electrodes to radiate the electromagnetic waves between the electrodes.

By controlling the high frequency voltage generated between the divided electrodes, the power of the electromagnetic wave radiated from between the electrodes can be controlled. As a control means of the high frequency voltage generated between the electrodes, the phase of the high frequency voltage applied to each electrode is controlled.

3) Since ions are accelerated by the high-frequency electric field and are incident on the electrode to which a high frequency is applied in the plasma processing chamber, the film adhering to the electrode surface is removed by the energy of the ions, and the deposition by the deposition film is performed. Reduced dust.

The electrode surface is made of a material that does not react with active species generated by the plasma treatment to generate a non-volatile substance. In addition, pressure is increased to increase heat transfer to the cooled electrode and reduce temperature fluctuations. The structure can be enhanced. This reduced dust generation due to the formation of non-volatile reactive products on the surface, reduced temperature fluctuations, stabilized the reaction on the surface, and prevented fluctuations in plasma processing characteristics.

In other portions, the temperature of the inner wall of the processing chamber was kept constant to prevent the occurrence of stress in the film due to heat fluctuation and prevent the film from peeling. In addition, by keeping the temperature constant, the reaction on the surface was stabilized, and the fluctuation of the plasma processing characteristics was prevented.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIGS.
As shown in FIG.

The first embodiment will be described with reference to FIG.

In FIG. 1, a support 3 for supporting a processing object is provided in a processing chamber 9, and a processing object 4 is placed on the support 3. The processing object 4 is, for example, a wafer for a semiconductor device. A part of the wall of the processing chamber is an electrode 2, and a parallel plate electrode is formed between the electrode and the support 3 which also has an electrode function. The support 3 and the processing object 4 are usually flat, but the electrode 2 may be flat.
It may have a step-like step as shown in FIG. 2A or a curved portion as shown in FIG.
Regardless of the case where the electrode 2 is shown in FIGS. 1, 2A, and 2B, a set of the electrode 2 and the support 3 is hereinafter referred to as a parallel plate electrode. Usually, the electrode 2 is in contact with the processing chamber 9, but a cover made of an insulator or the like may be provided between the electrode 2 and the processing chamber 9. The processing gas is introduced into the processing chamber 9 by the gas supply means 7. For example, as shown in FIG. 1, the electrode 2 may also function as a processing gas introduction path.

Further, the processing chamber 9 is evacuated by exhaust means (not shown), and is kept at a low pressure. The processing chamber 9
For example, it is surrounded by a cylindrical and grounded side wall 6,
The electrode 2 and the side wall 6 are electrically insulated by the insulating part 5. The power supply 1 is, for example, a combination of an AC power supply and a matching circuit. The processing gas in the processing chamber 9 is turned into plasma by the power applied by the power supply 1 to the parallel plate electrodes, and the plasma activates the processing gas to generate various types of active species. Further, the antenna 11 is provided near the insulator 5, and the insulator 5 has a function of a window for introducing the electromagnetic waves generated by the antenna 11 into the processing chamber 9. The antenna 11 may have one or more power input terminals and output terminals, and may be a loop antenna wound one or more turns, or a split loop antenna obtained by dividing one turn into a plurality. Any other shape may be used as long as the antenna emits electromagnetic waves. The power supply 12 supplies power to the antenna 11, but the power supply 1 may apply power to the electrode 2 and the antenna 11.

In the case where the antenna 11 induces a current in the electrode 2, for example, as shown in FIG. 3, if an insulating region such as a slit is provided in the electrode 2 so as to inhibit the induced current, the power of the antenna can be reduced. It may be easier to introduce it indoors. The antenna 11 induces an electric field 14 as shown in FIG. 1 in the processing chamber to generate plasma. Since the antenna generates plasma near the side wall 6, the state of the wall surface of the side wall 6 can be controlled by adjusting the power from the power supply 12.

The radicals excited by the plasma by the antenna 11 diffuse and permeate into the gaps between the parallel plate electrodes. However, since the radicals have a different composition from the active species excited by the plasma by the parallel plate electrodes, they are injected into the antenna. By adjusting the power to be applied, the radical composition inside the processing chamber can be controlled.

In the apparatus shown in FIG. 1, a magnetic field can be further applied to the processing chamber by the magnetic field generating means 13. For example, using a cylindrical solenoid coil, a magnetic field having a distribution as indicated by the magnetic field lines 15 can be generated. When the frequency of the electric field 14 and the strength of the magnetic field 15 are adjusted so as to cause electron cyclotron resonance when the oscillating electric field 14 generated by the antenna and the magnetic field lines 15 are substantially perpendicular, plasma can be generated particularly efficiently. For example, when the frequency of the oscillating electric field is 68 Mhz, electron cyclotron resonance occurs near a magnetic field strength of 24 Gauss.

Further, by adjusting the magnetic field intensity in a range close to the electron cyclotron resonance magnetic field, the radical component ratio can be adjusted, and the performance of fine processing can be optimized.

Further, in a place where the magnetic field strength is stronger than the electron cyclotron magnetic field, the electromagnetic wave can propagate in the plasma along the magnetic field. Therefore, as shown in FIG. 1, the distribution of the antenna and the magnetic field is set so that the magnetic lines of force passing through the antenna pass through the place in the processing chamber where the plasma is desired to be generated, thereby improving the efficiency of plasma generation.

Next, a second embodiment will be described with reference to FIG.

The apparatus shown in FIG. 4 has almost the same basic components as the apparatus shown in FIG. 1, except that the antenna 11 installed on the upper surface of the processing chamber 9 in FIG. 1 is installed on the side of the processing chamber. The points are different. In FIG. 4, although the electromagnetic wave of the antenna 11 is surrounded by the conductor wall 8 'so as not to leak outside, the conductor wall 8 and the conductor wall 8' may be integrated. Another feature of the apparatus of FIG. 4 is that the installation position of the magnetic field generating means 13 such as a solenoid coil is set downward so that the magnetic field lines 15 passing through the antenna 11 installed on the side of the processing chamber pass through the processing chamber. It is located at the point. Thereby, as described in the embodiment of FIG. 1, when a magnetic field stronger than the electron cyclotron resonance magnetic field is applied, the electromagnetic wave radiated by the antenna easily enters the plasma in the processing chamber, and the plasma generation efficiency is increased. I have.

Next, a third embodiment will be described with reference to FIG.

The apparatus shown in FIG. 5 has almost the same configuration as the apparatus shown in FIG. 4, except that the antenna 11 is installed inside the processing chamber. If the antenna is directly exposed to the plasma in the processing chamber and the antenna itself is shaved and adversely affects microfabrication, the antenna surface may be coated with a material that is difficult to be shaved by the plasma, or the antenna may be covered with a cover made of insulator. . By installing the antenna inside the processing chamber as in the embodiment of FIG. 5, the antenna can be provided even when there is not enough space for installing the antenna on the upper surface or the side surface of the processing chamber.

Next, a fourth embodiment will be described with reference to FIG.

The configuration of the device shown in FIG. 6 is the same as that of the device shown in FIG. 5, but is characterized in that the antenna 11 is provided above the electrode 2. In the case of the device of FIG. 6, the electrode 2 has an insulating portion such as a slit as shown in FIG. 3, and at least a part of the electromagnetic field induced by the antenna 11 propagates through the electrode 2 to the processing chamber 9, A plasma can be generated or energy can be given to the plasma. In this case, the plasma is generated by the parallel plate electrode and the antenna in the gap between the electrode 2 and the support 3, so that the electron energy of the plasma immediately above the object to be processed is adjusted by the input power of the antenna to improve the performance of fine processing. Becomes possible.

Next, a fifth embodiment will be described with reference to FIG.

The features of the device of FIG. 7 with respect to the device of FIG.
The point is that an antenna electrode 16 in which the antenna 11 and the electrode 2 of FIG. 1 are integrated is used.

FIG. 9 shows an example of the antenna electrode. The antenna electrode includes one or a plurality of electrode units 18, one or a plurality of antenna units 19 connected thereto, an input terminal 20, and an output terminal 21. An example of the antenna electrode is shown in FIG.
9 (b), 9 (c) and 9 (d) are shown. In particular, FIG.
In (c), a slit-shaped insulating region is provided so that the electromagnetic wave radiated from the antenna unit 19 inhibits the induced current generated in the electrode unit 18, thereby increasing the radiation efficiency of the electromagnetic wave of the antenna unit.

In the examples shown in FIGS. 7 and 9, the electrode portion and the antenna portion are substantially on the same plane, but the electrode portion and the antenna portion may have a three-dimensional structure. For example, there is an antenna electrode in which the antenna unit is installed right above the electrode unit.
A part of the power applied to the input terminal 20 by the power source 1 is used for plasma generation by the parallel plate electrodes formed by the electrode unit 18 and the support 3, and the rest is radiated as an electromagnetic wave from the antenna unit 19 to generate plasma in the processing chamber. Generate. The output terminal may be grounded, or may be grounded via a voltage maintaining means constituted by a capacitor or the like in order to maintain the voltage of the electrode portion of the antenna electrode.

Further, the input terminal and the output terminal may be switched and connected. When this antenna electrode is used, only one power source is required for each of the electrode and the antenna. In FIG. 7, the electrode portion of the antenna electrode is exposed to the processing chamber, and the antenna portion is outside the processing chamber. However, the electrode portion may be provided with a cover made of an insulator or the like.

As shown in FIG. 8, the antenna unit may be installed inside the processing chamber, or the antenna unit may be covered with a cover such as an insulator. The apparatus shown in FIGS. 7 and 8 has almost the same effect as the apparatus shown in FIG. 1, and can improve the performance of fine processing of an object to be processed.

Next, a sixth embodiment will be described with reference to FIG.

In the apparatus shown in FIG. 10, a power supply 12 for applying electric power between the outer peripheral electrode 23 and the side wall 6 to generate plasma is provided near the side wall 6 in the processing chamber. Outer electrode 23
Is generated near the side wall, the state of the side wall surface can be controlled, and the performance of fine processing can be improved. Further, if the frequencies of the power supply 1 and the power supply 12 are different, plasmas having different electron temperatures are generated, and the performance of fine processing can be optimized by adjusting the radical component ratio similarly to the apparatus of FIG. Further, the magnetic field generating means 13 is installed so that the direction of the electric field 14 ′ generated by the outer peripheral electrode 23 is almost perpendicular to the magnetic field lines 15, and if the magnetic field strength is set to be the electron cyclotron resonance magnetic field strength near the outer peripheral electrode, The efficiency of plasma generation by the electrodes can be increased.

Next, a seventh embodiment will be described with reference to FIG.

The processing chamber 51 includes stage electrodes 5.
2. Opposing electrodes: 53 are provided facing each other. The main body of the processing chamber 51 is formed of a grounded metal container, the upper part is formed of a quartz plate 54, and the joint between the processing chamber 51 and the quartz plate and each electrode has a vacuum seal structure. Processing chamber: The inside of the processing chamber 51 can be evacuated to a vacuum. Further, the processing chamber 51 has a processing gas supply mechanism (not shown), and the pressure in the processing chamber 51 can be controlled to a target pressure by an exhaust control mechanism (not shown) while supplying the processing gas.

The stage electrode 52 has a structure in which a processing substrate 55 can be placed, and the temperature of the processing substrate 55 during plasma processing can be controlled by a temperature control mechanism (not shown). The stage electrode 52 is connected to a bias power supply (2 MHz) 56 for controlling the energy of ions incident on the processing substrate.

Counter electrode: 53 is a high frequency application ring electrode:
53a, 53b, and an earth ring electrode: 53c, and a high-frequency power supply: 57 of 100 MHz is connected to the high-frequency application ring electrodes: 53a, 53b.
Earth ring electrode 53c is grounded.

A coil 58 is provided around the outer periphery of the processing chamber 51 so that a magnetic field can be formed in the processing chamber.

Next, an example of the operation in the etching process according to this embodiment will be described.

The processing substrate 55 is carried into the stage electrode 52 and placed thereon. An etching gas (carbon fluoride gas) is supplied at a set flow rate from an etching gas supply source (not shown), and the exhaust is controlled so that the pressure in the processing chamber becomes 1 Pa. A silicon oxide film and a silicon film which are insulating films of a semiconductor element are formed on the processing substrate. The processing substrate is electrostatically attracted to the stage electrode 52, and the substrate and the stage electrode 5 are supplied from a helium gas supply source (not shown).
He gas is supplied during the period 2 to prevent a temperature rise during the etching process of the processing substrate.

High frequency application ring electrode as counter electrode: 5
1.5 kW of high frequency power of 100 MHz is applied to 3a and 53b, and plasma is generated by discharge. Since the high-frequency application ring electrodes 53a and 53b and the vacuum atmosphere in the processing chamber are separated by the quartz plate 54, energy supply to the plasma is performed by capacitive coupling. In this case, since the electric field formed at the interface between the sheath and the plasma is small, the energy distribution of the electrons is close to the Maxwell-Boltzmann distribution.

A high-frequency electric field E is formed between the high-frequency application ring electrodes 53a, 53b and the earth ring electrode 53c, and a magnetic field is formed from the electric field, and an electromagnetic wave is radiated such that an electric field is formed. . The discharge due to capacitive coupling causes the plasma density to reach the order of 10 ¹⁰ / cm 3, so that the emitted electromagnetic wave cannot travel in the plasma, but an electric field is generated in the vicinity of the quartz plate: 54, and this electric field causes electrons to be generated. Can be directly accelerated and receive energy. In this case, the only electrons that receive energy are those near the quartz plate, and the ratio is small, but the energy level of the electrons is higher than that of plasma generated by capacitive coupling.

As described above, in the present embodiment, the energy supplied to the plasma includes two paths, that is, the path due to the capacitive coupling and the direct heating due to the high-frequency electric field. By changing the power ratio of the path, the energy state of the electrons can be changed. As a changing method, there is a method of changing the thickness of the quartz plate 54 and a method of changing the interval between the high-frequency ring electrode and the earth ring electrode. When the thickness of the quartz plate is increased, the impedance of capacitive coupling increases, the discharge voltage increases, the proportion of electromagnetic wave radiation increases, the proportion of power supplied by capacitive coupling decreases, and the energy level of electrons increases. When the distance between the high-frequency ring electrode and the earth ring electrode is reduced, the high-frequency electric field becomes stronger, the ratio of electromagnetic radiation increases, and the energy level of electrons also increases. By reversing the above, it is possible to approach the energy level due to the discharge of only the capacitive coupling.

Bias power supply: When 500 W of 2 MHz high frequency power is applied from 56, a voltage of 700 Vpp is generated, and ions from the plasma can be accelerated and incident on the substrate. The etching gas (carbon fluoride-based gas) reacts with the silicon oxide film and the silicon film, and the etching proceeds.

When the energy level of electrons is high, decomposition of the carbon fluoride gas proceeds, the amount of fluorine radicals increases, and the etching rate of the silicon film is improved. Further, under such a condition that the gas decomposition is advanced, the etching cross-sectional shape is almost vertical, and when the decomposition is not advanced, it tends to have a forward tapered shape. In the manufacture of semiconductor devices, it is necessary to make the etching rate of a silicon film as small as possible relative to the etching rate of a silicon oxide film as an insulating film, and to make the etching cross-sectional shape as close to vertical as possible. For this purpose, it is necessary to appropriately control the decomposition state of the carbon fluoride-based gas and find conditions for achieving both.

In the present invention, as described above, the decomposition state of the carbon fluoride-based gas can be controlled by adjusting the thickness of the quartz plate, the interval between the high-frequency ring electrode and the earth ring electrode, and the etching characteristics can be controlled. Can be optimized.

Further, high-frequency application ring electrodes 53a, 5a
3b, the distribution of the plasma can be changed by changing the size of the earth ring electrode.

Next, another method for controlling the electron energy in this embodiment will be described.

As described above, the high-frequency electric field E is formed between the high-frequency application ring electrodes 53a and 53b and the earth ring electrode 53c, and electromagnetic waves are radiated. However, in this embodiment, no magnetic field is applied. Therefore, the electromagnetic wave cannot travel into the plasma, but merely supplies energy to electrons near the quartz plate. In this control method, an electric current is applied to the coil 58 to form a magnetic field B so that the electromagnetic wave can travel in the plasma. In addition, the intensity of the magnetic field can be set to include the condition that causes electron cyclotron resonance with respect to the frequency of the electromagnetic wave, and the energy level given to the electrons is controlled by controlling the intensity of the electromagnetic wave emitted to the capacitively coupled discharge plasma and the magnetic field intensity. It was made possible to control to an appropriate electron energy state.

Even at a frequency of 100 MHz, there is a condition that the electromagnetic wave can travel in the plasma when a magnetic field is formed. At this time, the magnetic field must be almost perpendicular to the electric field of the electromagnetic wave. Therefore, the acceleration of the electrons by the high-frequency electric field is constrained by the magnetic field, and the energy received by the electrons from the high-frequency electric field is small and only slightly increases the energy state of the electrons. Therefore, it is effective for increasing the number of low energy electrons such as generation of active species.

When the intensity is set to 30 to 40 G, which is close to the magnetic field intensity that causes electron cyclotron resonance at 100 MHz, energy is efficiently supplied to the electrons in the plasma from the high-frequency electric field of the electromagnetic wave, and the energy level of the electrons is increased to the ionization level or higher. And decomposition of the etching gas can be promoted.

As described above, by changing the magnetic field intensity, the energy of electrons can be controlled from a level suitable for generating radicals to an ionization level or more. Characteristics can be optimized.

Next, an eighth embodiment will be described with reference to FIG.

This embodiment is another embodiment corresponding to the portions corresponding to the high frequency application ring electrodes 53a and 53b and the earth ring electrode 53c forming the counter electrode 53 shown in FIG.

As shown in FIG. 12, a high-frequency application plate electrode: 60 and an earth plate electrode: 61, and a high-frequency electric field is generated between the high-frequency application plate electrode: 60 and the earth plate electrode: 61, which face each other in a comb shape. Electromagnetic waves are emitted according to the same principle as described in Example 1. Further, the high frequency application plate supplies power to the plasma by capacitive coupling in the same manner as in the first embodiment.

The operation and function of the electronic energy state control are the same except for the above-mentioned points, and therefore are omitted here.

Next, a ninth embodiment will be described with reference to FIG.

The stage electrode: 5 in the processing chamber: 70
2. A counter electrode: 71 is provided facing the processing chamber, and the processing chamber and each electrode are insulated by an insulating material: 72a and an insulating material: 72b, and a joint with the processing chamber: 70 is a vacuum seal structure. And the inside of the processing chamber 70 can be evacuated to a vacuum. Counter electrode: 100 for 71
A high frequency power supply of MHz: 57 and a low pass filter: 73 are connected.

Processing chamber: 70 is grounded,
A coil 58 is provided on the outer periphery thereof to form a magnetic field in the processing chamber. Further, the processing chamber 70 has a processing gas supply mechanism (not shown), and the pressure in the processing chamber 70 can be controlled to a target pressure by an exhaust control mechanism (not shown) while supplying the processing gas.

The stage electrode 52 has a structure in which the processing substrate 55 can be placed, and the temperature of the processing substrate 55 during the plasma processing can be controlled by a temperature control mechanism (not shown). The stage electrode 52 is connected to a bias power supply (2 MHz) 56 for controlling the energy of ions incident on the processing substrate and a high-pass filter 74.

Next, an operation example of the etching process according to the present embodiment will be described.

In FIG. 13, a processing substrate 55 is carried in and placed on a stage electrode 52. An etching gas (carbon fluoride gas) is supplied at a set flow rate from an etching gas supply source (not shown), and the exhaust is controlled so that the pressure in the processing chamber becomes 1 Pa. A silicon oxide film and a silicon film which are insulating films of a semiconductor device are formed on the processing substrate.
The processing substrate is electrostatically attracted to the stage electrode 52, and a He gas is supplied between the substrate and the stage electrode 52 from a helium gas supply source (not shown) to prevent a temperature rise during the etching of the processing substrate. I do.

A high-frequency power of 100 MHz is applied to the opposing electrode 71 at 1.5 KW, and plasma is generated by discharge. A sheath is formed between the counter electrode 71 and the plasma, and energy is supplied to the plasma by capacitive coupling. In this case, since the electric field formed at the interface between the sheath and the plasma is small, the energy distribution of the electrons is close to the Maxwell-Boltzmann distribution.

A high-frequency electric field E is formed between the counter electrode 71 and the processing chamber 70, and an electromagnetic wave is emitted.

A current was passed through the coil 58 to form a magnetic field B, and the strength of the magnetic field could be set with respect to the conditions of causing electron cyclotron resonance with respect to the frequency of the applied high frequency.

[0093] Even at a frequency of 100 MHz, there is a condition under which a magnetic field can be formed so that an electromagnetic wave can travel in a plasma. At this time, the magnetic field must be substantially perpendicular to the electric field of the electromagnetic wave. Therefore, the acceleration of the electrons by the high-frequency electric field is constrained by the magnetic field, and the energy received by the electrons from the high-frequency electric field is small and only slightly increases the energy state of the electrons. Therefore, it is effective to increase low energy electrons such as generation of radicals.

When the magnetic field intensity is set to 30 to 40 G, which is close to the magnetic field intensity that causes electron cyclotron resonance at 100 MHz, energy is efficiently supplied to the electrons in the plasma from the high frequency electric field of the electromagnetic wave, and the energy level of the electrons is increased to the ionization level or more. Can be. Thus, by changing the magnetic field strength, the energy of electrons can be controlled from a level suitable for generating radicals to an ionization level or more.

When a high-frequency power of 2 MHz is applied from 500 to 500 W, a voltage of 700 Vpp is generated. Ions from the plasma are accelerated by this voltage and incident on the substrate, and are decomposed by the plasma on the surface of the substrate with the aid of ions. The etching gas (carbon fluoride gas) reacts with the silicon oxide film and the silicon film, and the etching proceeds.

If the energy level of electrons is high, decomposition of the carbon fluoride gas proceeds, the amount of fluorine active species increases, and the etching rate of the silicon film increases. Further, under such a condition that the gas decomposition is advanced, the etching cross-sectional shape is almost vertical, and when the decomposition is not advanced, it tends to have a forward tapered shape. In the manufacture of semiconductor devices, it is necessary to make the etching rate of a silicon film as small as possible relative to the etching rate of a silicon oxide film as an insulating film, and to make the etching cross-sectional shape as close to vertical as possible. For this purpose, it is necessary to appropriately control the decomposition state of the carbon fluoride-based gas and find conditions for achieving both.

In the present invention, the decomposition state of the carbon fluoride gas can be controlled by changing the magnetic field strength, and the etching characteristics such as the etching rate ratio and the etching shape between the silicon oxide film and the silicon film can be optimized by the pressure and the etching. It can be controlled independently of gas flow and high frequency power.

Next, a tenth embodiment will be described with reference to FIG.

The basic configuration of this embodiment is the same as that of the embodiment shown in FIG. 13, and only the differences will be described here.

The processing chamber 70 is not grounded, but a bias power supply of 800 KHz: 75 and a high-pass filter of 100 MHz are connected.

The stage electrode 77 has a built-in substrate heating mechanism (not shown).
It can be heated to a set value between degrees Celsius.

Next, an operation example of the plasma CVD process according to the present embodiment will be described.

The processing substrate 55 is loaded into the stage electrode 77 and placed thereon. A set flow rate of a CVD gas (silicon fluoride gas + oxygen gas) is supplied from a CVD gas supply source (not shown), and the exhaust is controlled so that the pressure in the processing chamber becomes 4 Pa. The processing substrate is placed on the stage electrode 77, and the temperature of the processing substrate is heated to 300 degrees Celsius. Counter electrode: 10 for 71
0MHz high frequency power, 1.5KW input and stage electrode:
Capacitatively coupled discharge is generated between the CVD gas 77 and the plasma gas.

A high voltage (1400 Vp) of 100 MHz is supplied to the opposing electrode 71 by power supplied from the high frequency power supply 57.
p) occurs, and a high-frequency electric field is generated between the processing chamber and 70. Although the processing chamber 70 is not grounded, it is in the same state as grounded by a high-pass filter 76 with respect to a high frequency of 100 MHz, and emits a high-frequency electromagnetic wave as in the embodiment shown in FIG.

The silicon fluoride gas is strongly bonded and does not decompose, and a large amount of fluorine is absorbed in the formed silicon oxide film. As in the embodiment shown in FIG. 13 by the action of an electromagnetic wave of 100 MHz and a magnetic field, silicon oxide is used to control the energy level of electrons, promote the decomposition of silicon fluoride gas, and exhaust the dissociated fluorine gas. Occlusion in the film is reduced, and the quality of the film can be improved. Further, since the decomposition of the silicon fluoride gas is promoted, the reaction between the dissociated silicon and the oxygen gas is also promoted, and the film formation rate can be improved.

In this embodiment, a high-pass filter: 74
And high-pass filter: By setting the frequency characteristic of 76 to 200 MHz, which is a multiple of the applied frequency, the applied frequency becomes 10 due to the nonlinear characteristic of the plasma sheath.
Resonance conditions can be created even when the frequency is a mixed frequency of 0 MHz and 200 MHz and the magnetic field strength is around 70 G. The mixing ratio of the double frequency can also be realized by changing the ratio between the reactance and the capacitance of the matching device.

In plasma CVD, a silicon oxide film is also formed on the inner wall of the processing chamber, and these are peeled off to form particles, which is a problem in manufacturing a semiconductor product.
In this embodiment, a bias power supply: 7 is provided on the inner wall of the processing chamber 70.
A high frequency voltage of 5 to 800 KHz can be applied, thereby increasing the incident ion energy, and the silicon oxide film formed on the inner wall surface of the processing chamber 70 is etched and removed by fluorine generated by decomposition of silicon fluoride gas. Therefore, no film is formed on the inner wall surface of the processing chamber during film formation, and generation of particles can be reduced.

Next, an eleventh embodiment will be described with reference to FIG.

The basic configuration of this embodiment is the same as that of the embodiment shown in FIG. 13, and only different points will be described here.

The counter electrode 71 includes a counter electrode 71a and a counter electrode 71b.
a, and an insulating material: 80b
And the processing chamber 70 is also insulated. A high-frequency power supply: 81 and a high-frequency power supply; 82 are connected to the respective electrodes. The high-frequency power supply: 81 and the high-frequency power supply: 82 generate the same frequency (100 MHz in this embodiment) out of phase. To be applied.

When high-frequency waves having different phases are applied to the counter electrode 71a and the counter electrode 71b, a high-frequency electric field is generated between the counter electrode 71a and the counter electrode 71b. Phase 18
When shifted by 0 degrees, the high-frequency electric field can be generated most efficiently, and when the phase shift is set to 0 degrees, the high-frequency electric field is weakest. By controlling the phase and the power of the high-frequency power supplies 81 and 82, the high-frequency electromagnetic wave power generated between the opposing electrodes 71a and 71b, the opposing electrode 71b, and the processing chamber:
It is possible to control the ratio of the high-frequency electromagnetic wave power generated between 70 and 70, thereby controlling the uniformity of the etching process and the plasma CVD process. Also high frequency power supply:
By controlling the power of 81 and 82, the ratio of the power supplied by capacitive coupling can be controlled, and the uniformity can be controlled.

Further, in this embodiment, two high-frequency power supplies are used, but one power supply supplies opposing electrodes 71a, 71b.
The same effect can be obtained by inserting a capacitance or a reactance between the power lines to be supplied to the power supply and shifting the phases.

Next, a twelfth embodiment will be described with reference to FIG.

Stage electrode: 5 in processing chamber: 70
2. A counter electrode 71 is provided to face the processing chamber 70, and the processing chamber 70 can be evacuated to a vacuum by an exhaust mechanism (not shown). I can keep it.

The counter electrode 71 is a counter electrode 71a, 71
b, 71c, and each electrode is made of quartz insulating material:
Insulated from each other by 80a and 80b. Further, the processing chamber 70 is insulated by the insulating material 80c.
High frequency power supply: 82, counter electrode: 7 for counter electrode: 71b
A high frequency power supply 81 is connected to 1c, and a high frequency power supply 81 is connected to the counter electrode 71a via a capacitor 83. The high frequency power supply 81 and the high frequency power supply 82 amplify the signal from the signal generator 97, and the signal generator 97 can control the phase and amplitude of the high frequency signal supplied to each power supply. ing. The signal frequency used in this embodiment is 100 MHz.

The corresponding electrodes 71a, 71b, and 71c are grounded via a low-pass filter (not shown), pass a 10 MHz frequency of a bias power supply of 56, and a high-frequency current of a bias power supply of 56 flows through the counter electrode. It is like that.

The opposing electrode 71 has a refrigerant flow path 84a,
84b and 84c are provided, connected to a circulator (not shown), and a temperature-controlled 15 ° C. refrigerant circulates.

The counter electrode 71 is provided with etching gas supply paths 85a, 85b and 85c, and is supplied with an etching gas from an etching gas supply source (not shown) and jets out from gas supply ports 86a, 86b and 86c. Has become.

The counter electrode 71 has a cover plate 87.
a, 87b, 87c are fixed. The cover plate 87a is made of a silicon single crystal plate, and the gas supply port 86aa is provided at a position corresponding to the gas supply port 86a, and its size is 1/4 to 1/10 of the gas supply port 86a. It has become. The cover plate: 87b is made of a silicon single crystal plate, and the gas supply port: 86bb
Is provided at a position corresponding to the gas supply port 86a, and the size is 1/4 to 1/10 of the gas supply port 86a. Cover plate 87c is made of SiC.

The processing chamber 70 is provided with flow paths 93a and 93b. A circulator (not shown) circulates a 50 ° C. refrigerant whose temperature is controlled, and controls the temperature of the inner wall surface of the processing chamber. It can be controlled to ± 5 ° C.

The processing chamber 70 contains a confinement plate 70.
a and 70b are integrally formed, and the exhaust path 94 is perpendicular to the magnetic field B formed by the coil 58. In this portion, the plasma diffuses across the magnetic field, so that the plasma is not spread and confined.

The stage electrode 52 has a bias power supply of 5
The configuration is such that high frequency power of 10 MHz to 6 MHz is supplied, and an insulating material: 89 and an earth shield: 90 do not cause abnormal discharge.

The stage electrode 52 is provided with a flow path 88, and a refrigerant at -10 ° C. is circulated from a circulator (not shown). Stage electrode: Processing substrate of 52: 55
Is provided with an electrostatic suction mechanism (not shown), and a pressure of 3K is supplied from a helium gas supply source (not shown).
Helium gas controlled to Pa is supplied between the processing substrate and the electrostatic suction mechanism, and the temperature of the processing substrate 55 during the etching process is controlled to 50 ° C to 100 ° C.

A quartz cover 91 is provided around the stage electrode 52. The thickness of the cover 91 is such that an electric field intensity for accelerating ions generated on the quartz cover surface by a high frequency of 10 MHz adheres to the quartz surface. The deposition film is removed and the quartz cover 91 is adjusted to a level that hardly etches. Also, cover: 91 and stage electrode: 5
2, a seal mechanism: 92 is provided, and a processing substrate:
Helium gas supplied between 55 and the electrostatic adsorption mechanism is supplied. Thus, the cover 91 is cooled by the stage electrode 52, and the temperature during the etching process can be controlled in the range of -10 ° C to + 10 ° C.

A deposit plate 95 is located downstream of the exhaust gas, and a coolant at 25 ° C. circulates in a flow path 96 formed therein. Fins are provided on the deposition plate 95 in a direction that does not increase the exhaust resistance so that a large surface area in contact with the exhaust gas can be obtained.

Next, an example of the operation in the etching process according to this embodiment will be described.

In this embodiment, a case where an oxide film is etched will be described.

A mixture of argon and C4F8 gas is supplied from an etching gas supply source (not shown), and the inside of the processing chamber 70 is controlled to 2 Pa while exhausting. The etching gas is supplied from gas supply ports: 86a, 86aa, 86b, 86bb. At this time, cover plates: 87a, 87b, 8
7c and counter electrode: 3KP between 71b, 71a, 71c
The etching gas of a is filled, whereby the cover plates 87a, 87b and 87c are cooled by the temperature-controlled counter electrode 71 and controlled to a temperature of 15 ° C to 50 ° C.

A signal generator: generates a high-frequency signal of 100 MHz from 97, a high-frequency power source: 81
High-frequency power is supplied from 82 to generate discharge between the stage electrode 52 and the stage electrode 52 by capacitive coupling.

A high frequency voltage is applied between the opposing electrode 71a and the opposing electrode 71c with a phase shift of 90 degrees by the capacitor 83. Counter electrode: 71b and counter electrode 71a
Can be set to an arbitrary shift from 0 degrees to 180 degrees by controlling the phase of the high-frequency signal by the signal generator 97. Therefore, the high frequency voltage generated during the insulating material 80a can be made higher or lower than the high frequency voltage generated during the insulating material 80b by controlling the phase of the signal generator 97. This gives insulation:
The electric power of the electromagnetic wave radiated from between 80a is 80
The power radiated from between b can be increased or decreased.

When power is supplied from a DC power supply (not shown) to the coil 58 and a magnetic field of 30 to 40 G is generated, electrons in the plasma are accelerated by electron cyclotron resonance with the emitted 100 MHz electromagnetic wave, and the electron temperature rises. As the plasma density increases, the plasma density increases to 1 × 10 ¹¹ cm ^−3.
The above plasma density can be generated. The counter electrode: 7
The distribution of the plasma density can be controlled by controlling the radiated electromagnetic waves by controlling the phase of the high-frequency voltage applied to 1. In addition, by controlling the outputs of the high frequency power supplies 81 and 82, the plasma distribution by the capacitively coupled discharge can be controlled, and the electron temperature distribution can be controlled by controlling the plasma distribution in accordance with the ratio of the radiated electromagnetic waves.

In this embodiment, the ratio of the power supplied to the capacitive coupling discharge to the outer peripheral portion is increased, and the ratio of the power supplied to the central portion of the discharge by the radiation of the electromagnetic wave is increased. As a result, the electron temperature in the central part is high and the peripheral part is low, so that the generation of fluorine radicals in the peripheral part where the decomposition of the etching gas progresses is suppressed, and uniform processing can be performed.

When a large-diameter substrate is processed, the thickness of the deposition film adhered to the substrate surface at the central portion is larger than that at the outer peripheral portion due to the influence of the flow of the etching gas. The taper angle becomes large, and a difference occurs in the etching shape between the central portion and the outer peripheral portion, which makes it difficult to form a fine etching shape with high precision over the entire surface of a large-diameter substrate. In such a case, in the present invention, the plasma density distribution is controlled to be slightly convex by increasing the electromagnetic radiation at the center, and the taper angle of the etched shape can be controlled by increasing the ion current at the center. High-precision etching processing can be realized on the entire surface of a substrate having a diameter. Further, in such a process, the phase of the signal of the signal generator 97 can be set by the recipe of the etching apparatus in the same manner as the setting of the process conditions. , Can be set appropriately individually, and there is no need to adjust hardware configuration and the like.

Regarding the etching performance, since high-density plasma can be generated even at a low pressure of 2 Pa, vertical contact holes can be etched at an etching rate of 900 nm / min, and both fine workability and productivity can be achieved. Regarding the selectivity, the decomposition of the etching gas can be controlled by controlling the electron temperature, and the process conditions for achieving both fine processing and selectivity can be expanded.

During the etching process, the surface of the cover plate 87a, 87b, 87c of the counter electrode 71 is temperature-controlled, and the ions in the plasma are accelerated and incident by the applied high-frequency voltage of 100 MHz. No deposit film is formed on the surface, and cover plate: 87
Since the surface of the silicon plate is slightly etched on the surfaces of the a and 87b and the surface of the cover plate 87c, SiC is slightly etched and a new surface is always exposed, so that the reaction and the gas release on this surface are constant. Will be kept.

Similarly, on the surface of the cover 91 of the stage electrode 52, the surface of the quartz is slightly etched by the acceleration of the incident ions and the temperature control by the application of the bias power.
Reaction and outgassing at the surface are kept constant.

Since the inner wall surface of the processing chamber 70 is grounded, incident ions are hardly accelerated, and a C and F polymer film is formed on the inner wall surface. Since the surface is constantly formed with a new film, it can be kept in a constant state. In addition, since the surface temperature is kept at 50 ° C, there is no gas release from the deposition film, and the surface state and gas release are constant. Can be kept.

Thus, it is possible to prevent a change in etching characteristics due to repeated etching,
Since no deposition film is formed on the counter electrode 71 and the stage electrode 52 and there is no deterioration of the surface, there is almost no generation of dust. As described above, the surface of the processing chamber 70 to which the deposition film adheres is kept at a constant temperature, so that no force is generated between the adhesion film and the wall surface of the processing chamber due to expansion or the like, and the film is separated. Does not occur. In this embodiment, the countermeasures against the counter electrode and the stage electrode significantly reduced the generation of dust.

In the above embodiments, etching and CVD have been mainly described. However, the present invention is not limited to this, and any other process using plasma, such as plasma polymerization and sputtering, can be applied. Is clear.

[0140] Regarding the frequency of the high frequency power supply for plasma generation, this embodiment has described the case where the frequencies are 68 MHz and 100 MHz. However, this is a description of the conditions under which the electromagnetic wave radiation effect is high. At a low frequency, a similar effect can be obtained by increasing the high-frequency voltage. Although the frequency is not limited in principle in principle, the frequency at which the effect of the experiment has been confirmed at present is 10 MHz or more. Higher frequencies can be used in principle, but at the present time it is difficult to make a power supply, a waveguide is required, the discharge voltage in capacitively coupled discharge is low, and the electromagnetic radiation power cannot be increased. Because of the problem, it was not described in this embodiment.

In the present embodiment, the magnetic field strength has been mainly described in the vicinity of the electron cyclotron resonance condition. However, experimental results show that the plasma density can be improved even under a magnetic field condition of about の of the electron cyclotron resonance condition. The change in plasma density with respect to the magnetic field intensity is such that the plasma density increases with the magnetic field up to the electron cyclotron condition, and the plasma density decreases when the magnetic field intensity is further increased. Depending on the process conditions, the plasma density decreases from twice to three times the electron cyclotron resonance condition. At twice the magnetic field strength, the plasma density level is reduced to the condition where no magnetic field is applied. Therefore, the magnetic field strength is not limited to the electron cyclotron resonance conditions,
The effect is large near the electron cyclotron resonance condition. This phenomenon means that the supply of energy from the radiated electromagnetic wave to the plasma can be controlled by the magnetic field by changing the magnetic field strength, indicating that the electron energy can be controlled by the magnetic field.

In the present embodiment, the description has been made mainly on the combined discharge of the capacitively coupled discharge and the electromagnetic radiation with respect to the plasma generation method. Since the purpose of this is to control the energy state of electrons, it has been mainly described. However, it is clear that the method of radiating the electromagnetic wave with the configuration in which the high-frequency voltage is applied between the insulated conductor members can generate plasma by itself, and can be one plasma generation technique. However, in this method, it is necessary to minimize the capacitance formed between the electrode and the plasma in order to prevent the high-frequency voltage from being lowered by the capacitive coupling component with the plasma.

The temperature control of the processing chamber 70 was set to 50 ° C. in the present embodiment, but is not limited to this. When the temperature of the inner wall surface exceeds 200 ° C., a deposit film is not formed on the surface, and a new deposit surface cannot be formed at all times. In addition, the decomposition of the adhered film rapidly increases at a temperature of 200 ° C. or more. Temperature must be set. Practically, it is 1 between the temperature of the environment where the device is used.
0 ° C to 80 ° C is a temperature that is easy to use.

[0144]

According to the present invention, in a plasma processing apparatus, the energy state of electrons can be controlled independently, thereby controlling the generation of active species and achieving high selective etching and high precision, high speed etching or film quality. Characteristics such as film speed, which are difficult to achieve with the conventional technology, are achieved.

The plasma density distribution can be controlled without changing the hardware configuration, and a fine pattern can be etched with high precision over the entire surface of a large-diameter substrate.

The generation of dust and the change in plasma processing characteristics due to the plasma processing can be prevented, and the productivity of semiconductor devices and liquid crystal display devices can be improved.

As a result, the performance of the processing of semiconductor elements, liquid crystal display elements, and the like can be improved, and higher-performance devices can be produced. In addition, these devices can be produced with high yield and high productivity. There is.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a plasma processing chamber according to a first embodiment of the present invention.

FIG. 2 is an explanatory view showing another example of the electrode structure shown in the first embodiment.

FIG. 3 is an explanatory view showing another example of the electrode structure shown in the first embodiment.

FIG. 4 is an explanatory diagram showing a configuration of a plasma processing chamber according to a second embodiment of the present invention.

FIG. 5 is an explanatory view showing a configuration of a plasma processing chamber according to a third embodiment of the present invention.

FIG. 6 is an explanatory view showing a configuration of a plasma processing chamber according to a fourth embodiment of the present invention.

FIG. 7 is an explanatory view showing a configuration of a plasma processing chamber according to a fifth embodiment of the present invention.

FIG. 8 is an explanatory view showing another example of the electrode structure shown in the fifth embodiment.

FIG. 9 is an explanatory view showing another example of the antenna electrode structure shown in the fifth embodiment.

FIG. 10 is an explanatory diagram showing a configuration of a plasma processing chamber according to a sixth embodiment of the present invention.

FIG. 11 is an explanatory view showing an electrode configuration of a seventh embodiment according to the present invention.

FIG. 12 is an explanatory diagram showing a configuration of a plasma processing chamber according to an eighth embodiment of the present invention.

FIG. 13 is an explanatory view showing a configuration of a plasma processing chamber according to a ninth embodiment of the present invention.

FIG. 14 is an explanatory view showing a configuration of a plasma processing chamber according to a tenth embodiment of the present invention.

FIG. 15 is an explanatory diagram showing a configuration of a plasma processing chamber according to an eleventh embodiment of the present invention.

FIG. 16 is an explanatory view showing a configuration of a plasma processing chamber according to a twelfth embodiment of the present invention.

FIG. 17 is an explanatory diagram showing a configuration of a conventional plasma processing apparatus.

[Explanation of symbols]

1 ... power supply, 2 ... electrode, 2 '... electrode, 2 "... electrode,
2 ″ ′: electrode, 3: support base, 4: object to be processed, 5: insulating section, 6: side wall section, 7: gas supply means, 8: conductor wall,
8 '... conductor wall, 9 ... processing room, 10 ... power supply, 11 ... antenna, 12 ... power supply, 13 ... magnetic field generating means, 14 ... electric field generated by antenna, 14' ... electric field generated by outer peripheral electrode, 1
5: magnetic field lines, 16: antenna electrode, 17: insulator cover, 18: electrode section, 19: antenna section, 20: power input end, 21: power output end, 22: insulating section, 23: outer peripheral electrode, 51: processing Chamber, 52 stage electrode, 53 counter electrode, 55 processing substrate, 56 bias power supply, 57 high frequency power supply, 58 coil, 70 processing chamber, 71 counter electrode, 81 high frequency power supply, 82 high frequency power supply , 87: cover plate, 91: cover.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/3065 H01L 21/31 C 21/31 21/302 B (72) Inventor Toshio Masuda 502, Kandachicho, Tsuchiura-shi, Ibaraki Prefecture Hitachi, Ltd. Within the Machinery Research Laboratory (72) Inventor Tetsunori Kaji 794, Higashi-Toyoi, Kazamatsu, Kudamatsu City, Yamaguchi Prefecture Inside the Kasado Factory, Hitachi, Ltd. Inside the Kasado Factory

Claims (18)

[Claims] 1. A plasma processing apparatus comprising: a plasma processing gas supply unit; a plasma processing chamber exhaust unit; a plasma generation unit; and a unit configured to expose a processing substrate to generated plasma and perform plasma processing. A plasma processing apparatus comprising a combined discharge unit and an electromagnetic wave emission unit. 2. The plasma processing apparatus according to claim 1, wherein said capacitively coupled discharge means and an electromagnetic wave radiating means by an inductive antenna are connected in series. 3. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave radiating means generates a high-frequency electric field between a plurality of conductor parts and radiates an electromagnetic wave. 4. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave radiating means divides a plurality of electrodes of said capacitively coupled discharging means for applying a high frequency voltage, and applies a high frequency voltage phase and a high frequency voltage applied between respective electrodes. A means for changing the amplitude is provided,
A plasma processing apparatus, wherein a high-frequency electric field is generated between the electrodes, and an electromagnetic wave is radiated by the high-frequency electric field. 5. A plasma processing apparatus comprising: a plasma processing gas supply means; a plasma processing chamber exhaust means; a plasma generation means; and a means for exposing a processing substrate to generated plasma and performing plasma processing. A plasma processing apparatus comprising a combined discharge unit, an electromagnetic wave emitting unit, and a magnetic field forming unit. 6. The plasma processing apparatus according to claim 5, wherein said electromagnetic wave radiating means is an induction type antenna. 7. The plasma processing apparatus according to claim 6, wherein said capacitively coupled discharge means and an inductive antenna means are connected in series. 8. The plasma processing apparatus according to claim 5, wherein said electromagnetic wave radiating means generates a high-frequency electric field between a plurality of conductor parts and radiates an electromagnetic wave. 9. The plasma processing apparatus according to claim 5, wherein said electromagnetic wave radiating means is provided between an electrode of a capacitively coupled discharging means for applying a high-frequency voltage and a component which is a conductor part insulated from said electrode. Means for generating a high-frequency electric field, and an electromagnetic wave is radiated by the high-frequency electric field. 10. The plasma processing apparatus according to claim 5, wherein said electromagnetic wave radiating means divides a plurality of electrodes of a capacitively coupled discharging means for applying a high frequency voltage, and a high frequency voltage phase and a high frequency voltage applied between the electrodes. A means for changing the amplitude is provided,
A plasma processing apparatus, wherein a high-frequency electric field is generated between the electrodes, and an electromagnetic wave is radiated by the high-frequency electric field. 11. A plasma processing apparatus according to claim 5, wherein said means for forming a magnetic field is formed so as to be substantially perpendicular to an electric field of an electromagnetic wave radiated by said electromagnetic wave radiating means. . 12. A plasma processing apparatus comprising: a plasma processing gas supply means; a plasma processing chamber exhaust means; a plasma generation means; and a means for exposing a processing substrate to generated plasma to perform plasma processing. A plasma processing apparatus for generating a high-frequency electric field between the conductive parts and radiating an electromagnetic wave to generate plasma. 13. A plasma processing apparatus comprising: a plasma processing gas supply unit; a plasma processing chamber exhaust unit; a plasma generation unit; and a unit for exposing a processing substrate to generated plasma to perform a plasma process. A high-frequency electric field is generated between the conductor parts, and a means for radiating an electromagnetic wave, and a magnetic field generating means for generating a magnetic field under conditions for generating an electromagnetic wave and electron cyclotron resonance radiated by the electromagnetic wave radiating means, Plasma processing equipment. 14. A plasma processing apparatus comprising: a plasma processing gas supply unit; a plasma processing chamber exhaust unit; a plasma generation unit; and a unit configured to expose a processing substrate to generated plasma and perform plasma processing in the plasma processing chamber.
The inner wall surface of the plasma processing chamber is constituted by either a surface having a means for accelerating ions incident from the plasma or a surface having means for keeping the inner wall temperature at a set temperature of 200 ° C. or less. Plasma processing equipment. 15. A plasma processing apparatus comprising: a plasma processing gas supply means; a plasma processing chamber exhaust means; a plasma generation means; and a means for exposing a processing substrate to generated plasma and performing plasma processing in the plasma processing chamber.
Either a surface having a means for controlling the temperature of the inner wall surface of the plasma processing chamber while accelerating ions incident from the plasma, or a surface having a means for maintaining the inner wall surface temperature at a set temperature of 200 ° C. or less. A plasma processing apparatus characterized by comprising: 16. A plasma processing method comprising: generating plasma by capacitive coupling in a plasma processing chamber; and performing plasma processing while radiating an electromagnetic wave generated by a high-frequency electric field in the plasma. 17. A plasma processing method according to claim 16, wherein a plurality of portions for radiating an electromagnetic wave generated by said high-frequency electric field into the plasma are provided, and the power of the electromagnetic wave radiated from said electromagnetic wave radiating portion is controlled. And a plasma processing method, wherein the plasma processing is controlled by controlling the uniformity of the plasma processing. 18. Plasma is generated by capacitive coupling in a plasma processing chamber, and an electromagnetic wave generated by a high-frequency electric field is radiated into the plasma, and plasma processing is performed while generating a magnetic field in a direction substantially perpendicular to the electric field of the electromagnetic wave. A plasma processing method characterized by the above-mentioned.