JP3710081B2 - Plasma processing equipment - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a plasma processing apparatus.
[0002]
[Prior art]
Conventionally, a plasma processing apparatus shown in FIG. 12 is known.
[0003]
In the conventional plasma processing apparatus, a matching circuit is interposed between the high frequency power source 1 and the plasma excitation electrode 4. The matching circuit is a circuit for obtaining impedance matching between the high-frequency power source 1 and the plasma excitation electrode 4.
[0004]
The high frequency power from the high frequency power source 1 is supplied to the plasma excitation electrode 4 by the power supply plate 3 through the matching circuit.
[0005]
These matching circuit and power feeding plate 3 are housed in a matching box 2 formed by a housing 21 made of a conductor.
[0006]
Below the plasma excitation electrode (cathode electrode) 4, a shower plate 5 in which a large number of holes 7 are formed is provided, and a space 6 is formed by the plasma excitation electrode 4 and the shower plate 5. A gas introduction pipe 17 is provided in the space 6. The gas introduced from the gas introduction pipe 17 is supplied into the chamber chamber 60 formed by the chamber wall 10 through the hole 7 of the shower plate 5. Reference numeral 9 denotes an insulator that insulates the chamber wall 10 from the plasma excitation electrode (cathode electrode) 4. The exhaust system is not shown.
[0007]
On the other hand, a wafer susceptor (susceptor electrode) 8 on which a substrate 16 is placed and also serves as a plasma excitation electrode is provided in the chamber chamber 60, and a susceptor shield 12 is provided around the wafer susceptor. The wafer susceptor 8 and the susceptor shield 12 can be moved up and down by a bellows 11, and the distance between the plasma excitation electrodes 4 and 8 can be adjusted.
[0008]
A second high frequency power supply 15 is connected to the wafer susceptor 8 via a matching circuit housed in the matching box 14.
The chamber and the susceptor shield 12 are at the same potential in terms of DC.
[0009]
FIG. 14 shows another conventional plasma processing apparatus.
Although the plasma processing apparatus shown in FIG. 12 is a so-called dual frequency excitation type plasma processing apparatus, the plasma processing apparatus shown in FIG. 14 is a single frequency excitation type plasma processing apparatus. That is, high-frequency power is supplied only to the cathode electrode 4, and the susceptor electrode 8 is grounded. There is no high-frequency power source 15 and matching box 14 shown in FIG. Further, the susceptor electrode 8 and the chamber wall 10 are at the same potential in terms of DC.
[0010]
FIG. 15 shows another conventional plasma processing apparatus.
In the plasma processing apparatus shown in FIG. 15, no shower plate is used, and the cathode electrode 4 serving as a plasma excitation electrode and the wafer susceptor 8 are directly opposed to each other. A shield 20 is provided around the back surface of the cathode electrode 4. Other points have the same configuration as the plasma processing apparatus shown in FIG.
[0011]
FIG. 16 shows another conventional plasma processing apparatus.
The plasma processing apparatus shown in FIG. 15 is a so-called dual frequency excitation type plasma processing apparatus, but the plasma processing apparatus shown in FIG. 16 is a single frequency excitation type plasma processing apparatus. That is, high-frequency power is supplied only to the cathode electrode 4, and the susceptor electrode 8 is grounded. There is no high-frequency power source 15 and matching box 14 shown in FIG. Further, the susceptor electrode 8 and the chamber wall 10 are at the same potential in terms of DC.
[0012]
However, when the conventional plasma processing apparatus is examined in detail, the power consumption efficiency (the ratio of the power consumed in the plasma to the power input from the high frequency power supply 1 to the plasma excitation electrode 4) is not necessarily good, As the frequency supplied from the high-frequency power supply increases, the power consumption efficiency decreases significantly. The present inventor has also found that the decrease is more remarkable as the substrate size increases.
[0013]
In the conventional plasma processing apparatus shown in FIGS. 12, 14, 15, and 16, the susceptor impedance (impedance between the susceptor and the chamber) is high, and the frequency of the high frequency supplied from the high frequency power sources 1 and 15 is high. As becomes higher, the impedance becomes even larger. That is, these impedances have frequency dependence. Therefore, as the frequency of the high frequency supplied from the high frequency power source 1 increases, the high frequency current flowing through the plasma in series with the susceptor impedance decreases, and the power consumption efficiency decreases significantly.
[0014]
The power consumption efficiency was investigated as follows.
(1) Replace the chamber wall of the plasma processing apparatus with an equivalent circuit composed of a lumped constant circuit.
(2) Determine the constants of each circuit by measuring the impedance of the components of the chamber using an impedance analyzer.
(3) Using the fact that the impedance of the entire chamber during discharge is in a complex conjugate relationship with the impedance of the matching box with a dummy load of 50Ω on the input side, the impedance of the entire chamber during discharge is known.
(4) The plasma space is regarded as a series circuit of a resistor R and a capacitor C, and the respective constants are calculated from the values obtained in (2) and (3).
(5) Based on the equivalent circuit model of the chamber during discharge obtained by the above method, circuit calculation is performed to derive power consumption efficiency.
[0015]
As described above, in the conventional plasma processing apparatus, the film formation rate is slow because the power consumption efficiency is low, and it is difficult to form an insulating film having a higher withstand voltage in the case of forming an insulating film, for example. Has the problem.
[0016]
The inventor has eagerly searched for the cause of low power consumption efficiency. As a result, we obtained the knowledge that the cause of low power consumption efficiency is the following.
[0017]
That is, first, on the susceptor electrode 8 side of the conventional plasma processing apparatus shown in FIG. 12, the high frequency power is supplied from the high frequency power source 1 as shown by the arrow in FIG. A coaxial cable, a matching circuit, a power supply plate 3 and a plasma excitation electrode (cathode electrode) 4 are supplied. On the other hand, when considering the path of the high-frequency current, the current passes through the plasma space (chamber chamber 60) through these, and then the other electrode (susceptor electrode) 8, the vertical portion of the shield 12, the bellows 11, the chamber It passes through the bottom 10b of the wall 10 and the side wall 10a of the chamber wall 10. Then, it passes through the housing of the matching box 2 and returns to the ground of the high frequency power source 1.
[0018]
Also in the plasma processing apparatus shown in FIG. 14, the high frequency power from the high frequency power source 1 is supplied from the high frequency power source 1 to the cathode electrode 4 through the coaxial cable, the matching circuit, and the power feeding plate 3. On the other hand, when considering the path of the high frequency current, the current passes through the plasma space through these, and then the other electrode (susceptor electrode) 8, the shaft 13, the bottom 10 b of the chamber wall 10, and the side wall of the chamber wall 10. It passes 10s. Then, it passes through the housing of the matching box 2 and returns to the ground of the high frequency power source 1.
[0019]
However, in the conventional plasma processing apparatus shown in FIGS. 12 and 14, the shaft 13 of the susceptor electrode 8 (or the vertical portion of the shield 12) and the chamber side wall 10a are parallel to each other. However, the vertical portion of the shield 12 and the chamber side wall 10s become parallel to each other, resulting in an increase in mutual inductance. As a result, the power consumption efficiency is lowered, and as a result, the film forming speed is lowered or the film quality is lowered. In particular, the influence of the mutual inductance becomes more significant as the substrate 16 becomes larger and, as a result, the distance between the power supply plate 3 and the housing of the matching box 2 becomes larger, and becomes prominent when the substrate becomes 80 to 100 cm.
[0020]
In addition, knowledge including this subject was found for the first time by the present inventors.
[0021]
[Means for Solving the Problems]
The plasma processing apparatus of the present invention has a plasma excitation electrode to which power for plasma excitation is supplied in a chamber chamber for performing plasma processing , and is opposed to the plasma excitation electrode and has the same DC potential as the chamber wall of the chamber chamber. A susceptor electrode , and the susceptor electrode is an electrode into which a high-frequency current generated by the plasma excitation power flows after passing through a plasma space, and the chamber wall and the susceptor electrode are short-circuited in an alternating manner. It is characterized by.
[0022]
Here, it is preferable that the chamber wall and the susceptor electrode are electrically connected .
[0023]
Moreover, it is preferable that the point which short-circuits the said susceptor electrode and the said chamber wall exists in the range below 500 mm in the horizontal direction from the said chamber side wall. Furthermore, it is preferable that the point where the susceptor electrode and the chamber wall are short-circuited on the chamber side is in a range of less than 500 mm in the horizontal direction from the chamber side wall. Furthermore, it is preferable that the chamber wall and the susceptor electrode are short-circuited at a plurality of points.
[0024]
Here, it is preferable that a short-circuit point that short-circuits the chamber wall and the susceptor electrode is substantially point-symmetric with respect to the center of the electrode. Further, it is preferable that a short-circuit point for short-circuiting the chamber wall and the susceptor electrode is substantially point symmetric with respect to the shield center .
[0025]
Furthermore, the plasma processing apparatus of the present invention is provided with a plasma excitation electrode to which power for plasma excitation is supplied and a high-frequency current generated by the plasma excitation power in a chamber chamber for performing plasma processing. A susceptor electrode that flows after passing through the plasma space, and a susceptor shield that is provided around the susceptor electrode and that has the same potential as the chamber wall of the chamber chamber, and the chamber wall and the susceptor shield Are short-circuited in an alternating manner.
[0026]
Here, it is preferable that the chamber wall and the susceptor shield are electrically connected. Furthermore, it is preferable that the susceptor shield and the chamber wall are short-circuited.
In the present invention, the point on the chamber side is preferably within a range of less than 500 mm in the horizontal direction from the side wall of the chamber chamber, and each point where the susceptor shield and the chamber wall are short-circuited. It is preferable that the distance is less than 500 mm in the horizontal direction from the side wall of the chamber.
Furthermore, in the present invention, it is preferable that the chamber wall and the susceptor shield are short-circuited at a plurality of points, and the short-circuit point that short-circuits the chamber wall and the susceptor shield is substantially the center of the susceptor electrode. It is preferably point-symmetric.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment of plasma processing apparatus)
FIG. 1 shows a first embodiment of a plasma processing apparatus of the present invention. In this plasma processing apparatus, the chamber wall 10 and the shield 12 of the electrode having the same DC potential as that of the chamber are short-circuited by metal plates 80a and 80b.
[0028]
FIG. 2 shows details of the wafer susceptor electrode 8 side.
In this example, AC short-circuit between the chamber wall 10 and the shield 12 is performed at two locations. In this short circuit, the elastic metal plates 80a and 80b are connected at one end to the bottom 10b of the chamber wall 10 at the short-circuit points B1 and B2, and the other end is connected to the shield 12 at the short-circuit points A1 and A2. It is done by doing. The short-circuit points B1 and B2 are arranged in the vicinity of the outermost periphery of the shield 12, and the distance from the side wall 10s of the chamber wall 10 is made as small as possible. That is, it is preferable to set the short-circuit points B1 and B2 from the side wall 10s of the chamber wall 10 to the closest point or the vicinity thereof.
[0029]
Inconel 625 (trade name) is preferably used as the material of the metal plate from the viewpoint that the amount of gas released in vacuum is small. In this example, a metal plate having dimensions of 20 mm × 40 cm × 0.3 mm was used. .
[0030]
In addition, although the plate-shaped thing was used in this example, it is also preferable to use a mesh-shaped thing. The shape of the mesh is preferably a turtle shape or a lattice shape shown in FIG. The mesh metal plate is preferably arranged in a cylindrical shape along the periphery of the susceptor shield 12. FIG. 3B is a cross-sectional view taken along the line III-III in FIG. 1, and is a diagram in which a turtle-like mesh metal plate shown in FIG. 3A is arranged in place of the metal plates 80a and 80b. Since the metal plate is mesh-shaped, the evacuation of the chamber chamber is not hindered by the metal plate, and the flow of high-frequency current can be made uniform. Moreover, it is rich in elasticity and easily follows the vertical movement of the bellows.
[0031]
In this example, the short-circuit points A1 and A2 in the shield 12 are set almost immediately above the short-circuit points B1 and B2.
[0032]
In the plasma processing apparatus of this example, high frequency power is supplied from a high frequency power source 1 to a coaxial cable, a matching circuit, a power feeding plate 3 and a plasma excitation electrode (cathode electrode) 4. This is the same as the conventional plasma processing apparatus. On the other hand, when considering the path of the high frequency current, the current passes through the plasma space (chamber chamber 60) through these, and then the other electrode (susceptor electrode) 8, the horizontal portion of the shield 12, the metal plate 80a, 80 b passes through the bottom 10 b of the chamber wall 10 and the side wall 10 a of the chamber wall 10. Then, it passes through the housing of the matching box 2 and returns to the ground of the high frequency power source 1.
[0033]
In the conventional plasma processing apparatus, the high-frequency current has passed through the vertical portion of the shield 12. As the size of the substrate 16 increases, the distance between the shield 12 and the chamber sidewall necessarily increases. Since the mutual inductance generated by the high-frequency currents flowing through the shield 12 and the chamber side wall 10s increases as the distance between them increases, the power consumption efficiency decreases. Therefore, the conventional plasma processing apparatus consumes power for a large-sized substrate. The efficiency had to be low.
[0034]
However, in the plasma processing apparatus according to the present example, the high-frequency current passes through the metal plates 80a and 80b closer to the chamber side wall 10s than the vertical portion of the shield 12, so that the generation of mutual inductance is remarkably reduced and the power consumption efficiency is remarkably increased. Can do.
[0035]
An insulating film made of silicon nitride is formed using the apparatus shown in FIG. 1 and the apparatus shown in FIG. 12, and the power consumption efficiency at that time is measured. In the case of the apparatus shown in FIG. 1, the apparatus shown in FIG. Compared with the case of, the power consumption efficiency was double.
[0036]
In addition, susceptor impedance was measured. The result is shown in FIG. (A) is the case of the plasma processing apparatus shown in FIG. 12 (conventional example), and (b) is the case of the plasma processing apparatus shown in FIG.
[0037]
As can be seen from FIG. 4, in the plasma processing apparatus according to this example, the susceptor impedance is much smaller than that of the plasma processing apparatus according to the conventional example, and the frequency dependency is small.
[0038]
(Second Embodiment of Plasma Processing Apparatus)
FIG. 5 shows a plasma processing apparatus according to the second embodiment.
This example is an example in which metal plates 80a and 80b are provided in the plasma processing apparatus shown in FIG. 14, that is, a single frequency excitation type plasma processing apparatus.
[0039]
In other words, the chamber wall 10 and an electrode (susceptor electrode 8) having the same potential as that of the chamber are short-circuited by the metal plates 80a and 80b.
The other points are the same as in the first embodiment.
[0040]
(Third embodiment of plasma processing apparatus)
In this example, the influence of the position where the metal plate is provided was examined.
[0041]
That is, in the apparatus shown in FIG. 1, the short-circuit points B1 and B2 of the metal plate in the chamber wall 10 are directly below the short-circuit points A1 and A2 of the metal plate in the shield 12, and the distance x from the short-circuit point to the chamber side wall 10a is changed. The magnitude of mutual inductance was investigated.
[0042]
The result is shown in FIG.
As can be seen from FIG. 6, the inductance starts decreasing when the distance x is 500 mm, the decreasing rate increases from around 350 mm, and the decreasing rate increases more rapidly from around 200 mm.
[0043]
Accordingly, the position of the short-circuit point is preferably less than 500 mm from the chamber side wall, more preferably less than 350 mm, and even more preferably less than 200 mm. Most preferred is the point at or near the shortest distance from the chamber sidewall 10a.
[0044]
(Fourth embodiment of plasma processing apparatus)
In this example, the influence of the number of metal plates arranged was examined.
[0045]
That is, the number of metal plates was changed and the magnitude of the inductance was measured. The metal plate was arranged approximately point-symmetrically with respect to the center of the shield.
The result is shown in FIG.
[0046]
As shown in FIG. 7, the inductance starts to decrease by arranging the metal plate, but the reduction rate is almost the same when four or eight are arranged. That is, saturation starts from around four. Therefore, it is preferable to provide four. In addition, when a square electrode is used, the path through which the high-frequency current flows is made uniform, and considering that the plasma treatment effect is uniformly applied to the workpiece placed in the center of the square electrode, the metal plate is It is preferable to provide four or eight.
[0047]
(Fifth embodiment of plasma processing apparatus)
FIG. 8 shows a fifth embodiment.
[0048]
In this example, the metal plate 80a is disposed obliquely. That is, one end of the metal plate 80a is short-circuited at the point B1 closest to the chamber side wall in the shield 12, and the other end of the metal plate 80a is not directly under B1, but is short-circuited at the point A1 from the chamber side wall so that the metal plate is slanted. Is arranged. In the case where the metal plate 80a is disposed obliquely, the inclination angle θ is preferably less than 45 ° from the viewpoint of suppressing mutual inductance.
[0049]
In the fifth embodiment, the power consumption efficiency is further increased as compared with the case of the first embodiment.
[0050]
(Sixth embodiment of plasma processing apparatus)
FIG. 9 further shows a sixth embodiment.
[0051]
In this example, the metal plate 80a is arranged substantially perpendicular to the chamber side wall 10a, that is, substantially horizontally on the susceptor electrode 8.
In this example, the power consumption efficiency is further increased than in the case of the fifth embodiment.
[0052]
(Seventh embodiment of plasma processing apparatus)
FIG. 10 shows a seventh embodiment.
[0053]
This example is an example in which a metal plate is provided in the conventional plasma processing apparatus shown in FIG.
[0054]
The other points are the same as in the first embodiment.
The plasma processing apparatus according to this example was also superior in power consumption efficiency, film formation rate, and withstand voltage than the conventional plasma processing apparatus shown in FIG.
[0055]
(Eighth embodiment of plasma processing apparatus)
FIG. 11 shows an eighth embodiment.
[0056]
This example is an example in which a metal plate is provided in the conventional plasma processing apparatus shown in FIG.
The other points are the same as in the first embodiment.
[0057]
The plasma processing apparatus according to this example was also superior in power consumption efficiency, film formation rate, and withstand voltage than the conventional plasma processing apparatus shown in FIG.
[0058]
In the above-described invention, it has become possible to improve the power consumption efficiency as compared with the prior art by reducing the impedance.
[0059]
However, the desired power consumption efficiency is still not achieved.
The inventor searched for the cause, and obtained the idea that the cause might be the impedance of the high-frequency power source 1 or the impedance of the matching circuit.
[0060]
That is, conventionally, since the substrate size is smaller than 80 cm, the plasma density is not high, and the frequency used is 13.56 MHz, the impedance of the high frequency power supply and the impedance of the matching circuit affect the power consumption efficiency. It never happened. However, a high plasma density can be achieved, the substrate size is increased, and the impedance of the high-frequency power source and the impedance of the current matching circuit have an effect on the power consumption efficiency when the frequency used exceeds 13.56 MHz. I got the idea that I couldn't ignore it. Conventionally, the resistance value of the high-frequency power source is 50Ω.
[0061]
A test was conducted based on such an idea. When a frequency exceeding 13.56 MHz is used, the power consumption efficiency is improved when the resistance value of the high-frequency power source is less than 50Ω and the resistance value of the matching circuit is less than 50Ω. I found. Note that 10Ω or less is more preferable.
[0062]
The fixture (specimen) is used in an impedance measuring device and a measuring method of a plasma device used for manufacturing semiconductors, LCDs, MR heads, and the like.
The conventional technique for the fixture is as follows.
[0063]
In the film forming process and the etching process, a plasma apparatus using plasma generated by glow discharge using a high-frequency power source is used. In such a process, due to the parasitic impedance of the device, the ratio of the effective power that is effectively consumed in the plasma space out of the input power is reduced, which affects the film formation speed and film breakdown voltage, Productivity and film quality were reduced. In order to improve this, it was necessary to quantitatively grasp the impedance parasitic on the device.
[0064]
For such measurement, an impedance analyzer having a coaxial probe or a network analyzer is used. However, due to restrictions on the probe shape, there are limitations on the size of the measurement object or the distance between two measurable points.
[0065]
Conventionally, as a method of dealing with this problem, a lead wire having a length corresponding to the size of the object to be measured and the distance between two points to be measured is attached as a fixture to the earth side of the probe as a fixture. A method of correcting and using the impedance is the simplest method.
[0066]
However, the conventional fixture has the following problems.
(1) Since the current flows through the measurement object asymmetrically, only a partial impedance of the measurement object is measured, and an accurate impedance cannot be known.
(2) Since the current is limited by the impedance of the ground wire attached as a fixture, low impedance measurement cannot be performed accurately.
[0067]
Residue that does not affect the measurement of the impedance of the measurement object without restricting the size of the measurement object or the distance between the two points to be measured, and allowing the current to flow uniformly through the measurement object For the purpose of providing a dedicated fixture that can be designed to an impedance value and a measuring method thereof, the present inventor has considered a novel impedance measuring tool.
[0068]
(First Embodiment of Impedance Measuring Tool)
A first embodiment of the impedance measuring tool according to the present invention will be described with reference to FIG. This fixture is characterized in that one end of a plurality of conducting wires 101a to 101h having the same impedance is connected to the probe fixture 104.
[0069]
The probe fixture 104 is formed, for example, from a copper plate of 50 mm × 10 mm × 0.5 mm so that the tightening portion 106 and the ring portion can be formed. The ring portion has a diameter that can be fitted to the outside of the probe 105.
[0070]
One end of the conducting wires 101a to 101h is electrically connected to the probe mounting portion 104 by soldering or the like.
[0071]
Terminals (crimp terminals) 102a to 102h for attaching to and detaching from the measurement target (object to be measured) are attached to the other ends of the conducting wires 101a to 101h.
[0072]
When using this fixture, the ring-shaped portion 104 of the probe fixture 104 is fitted into the probe 105 and tightened by the tightening portion 106. On the other hand, the lead wires 101a to 101h are detachably screwed to the object to be measured at the crimp terminals 102a to 102h by screws 114 as shown in FIG. As shown in FIG. 23, the probe 105 is formed by providing an insulating coating 112 on a conducting wire 110 and coating an outer peripheral conductor 111 on the insulating coating 112. The probe 105 is connected to an impedance measuring device (not shown) through a coaxial cable.
[0073]
The conductors 101a to 101h may be made of, for example, aluminum, copper, silver, or gold, or may be formed by plating silver or gold by 50 μm or more.
[0074]
After arranging the fixture in this way, the impedance of the object to be measured was measured. The result is shown in FIG. FIG. 19A shows the result of the conventional example, and FIG. 19B shows the result of this example. Note that the measurement of the conventional example of FIG. 19A was performed using the probe 105 shown in FIG.
[0075]
The impedance Z is represented by ωL−1 / ωC, and there is an inflection point between a hyperbola representing 1 / ωC and a straight line representing ωL at a certain frequency f ₀ , and the phase changes at that point. However, this point is not clearly shown in FIG. 19A showing the result of the conventional example. On the other hand, in FIG. 19B showing the result of this example, the hyperbola, the straight line, and the inflection point clearly appear at the frequency f ₀ , indicating that the impedance was accurately measured.
[0076]
In addition, it is preferable to use copper with a small specific resistance for the conducting wires 101a to 101h from the consideration that the current is limited by the impedance of the conducting wires 101a to 101h. By using the conducting wire, there is an advantage that the parasitic capacitance between the measuring object can be reduced.
[0077]
Next, using the impedance measuring instrument described in this embodiment, the plasma excitation electrode (cathode electrode) 4, the plasma space 60, the susceptor electrode 8, and the shield 12 are horizontally arranged from the power supply plate 3 of the plasma processing apparatus shown in FIG. A method of measuring the impedance of the path leading to the metal plate 80a, 80b, the bottom 10b of the chamber wall 10, the side wall 10a of the chamber wall, and the housing 21 will be described with reference to FIG.
[0078]
First, the high frequency power source 1 and the matching box 2 of the plasma processing apparatus are removed from the plasma processing apparatus. The conducting wire 110 of the probe 105 of the impedance measuring tool is connected to the conducting wire 113 that connects the matching box 2 and the power feeding plate 3. Next, the crimp terminals 102a to 102h connected to the lead wires 101a to 101h of the fixture of the impedance measuring tool are screwed to the housing 21 of the plasma processing apparatus with screws 114 so as to be substantially point-symmetric about the power supply plate 3. After the impedance measuring tool is arranged in this way, a measurement signal is supplied to the lead wire 110 of the impedance measuring tool, and the impedance of the path from the power supply plate 3 of the plasma processing apparatus to the housing 21 through the plasma space 60 is measured.
[0079]
This fixture is attached to a measurement probe calibrated at 0S, 0Ω, and 50Ω, respectively. The effect of the residual impedance of this fixture can be solved by correcting for open and short. . Note that the same effect can be obtained as shown in FIG. 20 even if the calibration is applied to the probe to which the fixture is attached.
[0080]
(Second Embodiment of Impedance Measuring Tool)
FIG. 18 shows a second embodiment of the impedance measuring instrument according to the present invention. This impedance measuring tool is used when a measurement target is large, and a plurality of conducting wires 101a to 101h are short-circuited by another short-circuiting conducting wire 108.
[0081]
According to this impedance measuring instrument, the impedance of the specimen can be reduced because the path of the measurement current increases. As a result, the ratio of the impedance of the object to be measured occupying the impedance of the entire measurement system including the object to be measured becomes high, and impedance measurement with higher accuracy is possible.
[0082]
(Third Embodiment of Impedance Measuring Tool)
FIG. 22 shows a third embodiment according to the impedance measuring instrument of the present invention. In the present embodiment, one end of the plurality of conductive wires 101a to 101h in the first embodiment described above is directly soldered to the outer peripheral conductor 111 of the probe 105 with the solder terminal portion 121 without using a probe fixture. Unlike the first embodiment, the other parts are the same as in the first embodiment. Also in this embodiment, the same effect as that of the first embodiment according to the impedance measuring instrument of the present invention was obtained.
[0083]
【The invention's effect】
According to the present invention, it is possible to increase the power consumption efficiency, to form a film with a higher quality and a higher quality film than before. Further, the susceptor impedance can be reduced and the frequency dependency can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a plasma processing apparatus according to a first embodiment of the plasma processing apparatus.
FIG. 2 is an enlarged view of the vicinity of a susceptor electrode in FIG.
3A is a partial side view of a mesh-like metal plate, and FIG. 3B is a plan view thereof.
FIG. 4 is a graph showing measurement results according to the first embodiment and a conventional example of a plasma processing apparatus.
FIG. 5 is a cross-sectional view of a plasma processing apparatus according to a second embodiment of the plasma processing apparatus.
FIG. 6 is a graph showing the relationship between the distance between the metal plate and the chamber wall and the mutual inductance.
FIG. 7 is a graph showing the influence of the number of metal plates arranged.
FIG. 8 is a cross-sectional view showing a part of a plasma processing apparatus according to a fifth embodiment of the plasma processing apparatus.
FIG. 9 is a cross-sectional view showing a part of a plasma processing apparatus according to a sixth embodiment of the plasma processing apparatus.
FIG. 10 is a cross-sectional view showing a plasma processing apparatus according to a seventh embodiment of the plasma processing apparatus.
FIG. 11 is a cross-sectional view showing a plasma processing apparatus according to an eighth embodiment of the plasma processing apparatus.
FIG. 12 is a cross-sectional view of a plasma processing apparatus according to a conventional example.
13 is a partially enlarged view of the susceptor electrode shown in FIG. 12 and its peripheral portion.
FIG. 14 is a cross-sectional view of a plasma processing apparatus according to another conventional example.
FIG. 15 is a cross-sectional view of a plasma processing apparatus according to another conventional example.
FIG. 16 is a cross-sectional view of a plasma processing apparatus according to another conventional example.
FIG. 17 is a diagram showing a first embodiment according to the impedance measuring instrument of the present invention.
FIG. 18 is a diagram showing a second embodiment according to the impedance measuring instrument of the present invention.
FIG. 19 is a graph showing the results of measurement using the impedance measuring tool shown in FIG.
20 is a graph showing the results of measurement using the impedance measuring tool shown in FIG.
21 is a diagram showing a method of measuring the impedance of the plasma processing apparatus shown in FIG. 1 using the impedance measuring tool shown in FIG.
FIG. 22 is a perspective view showing a third embodiment of the impedance measuring instrument of the present invention.
23 is a perspective view showing a probe used in the impedance measuring instrument shown in FIGS. 17, 18 and 22. FIG.
[Explanation of symbols]
1 high frequency power supply,
2 matching boxes,
3 Power supply plate,
4 Plasma excitation electrode (cathode electrode),
5 shower plate,
6 space,
7 holes,
8 Plasma excitation electrode (wafer susceptor, susceptor electrode),
9 Insulator,
10 chamber walls,
10a chamber sidewall,
10b chamber wall bottom,
10s chamber sidewall,
10u upper chamber,
11 Bellows,
12 Susceptor shield,
13 shaft,
14 Matching box,
15 high frequency power supply,
16 substrates,
17 Gas introduction pipe,
21 housing,
20 Shield,
60 chamber chamber,
80a, 80b metal plate,
101a to 101h conducting wire,
102a to 102h crimp terminal,
104 probe fixture,
105 probes,
106 Tightening part,
111 outer conductor,
112 insulation coating,
114 screws,
121 short-circuit point,
A1, A2 short circuit point,
B1, B2 Short circuit point.

Claims (12)

A plasma excitation electrode to which power for plasma excitation is supplied into a chamber for performing plasma treatment;
A susceptor electrode facing the plasma excitation electrode and having the same DC potential as the chamber wall of the chamber chamber;
The susceptor electrode is an electrode into which a high-frequency current generated by the plasma excitation power flows after passing through the plasma space;
A plasma processing apparatus, wherein the chamber wall and the susceptor electrode are short-circuited in an alternating manner.   The plasma processing apparatus according to claim 1, wherein the chamber wall is electrically connected to the susceptor electrode.   3. The plasma according to claim 1, wherein a point on the chamber side that short-circuits the susceptor electrode and the chamber wall is in a range of less than 500 mm in a horizontal direction from a side wall of the chamber chamber. Processing equipment. 4. The plasma processing apparatus according to claim 3, wherein each point where the susceptor electrode and the chamber wall are short-circuited is within a range of less than 500 mm in a horizontal direction from a side wall of the chamber chamber.   The plasma processing apparatus according to claim 1, wherein the chamber wall and the susceptor electrode are short-circuited at a plurality of points.   6. The plasma processing apparatus according to claim 5, wherein a short-circuit point for short-circuiting the chamber wall and the susceptor electrode is substantially point symmetric with respect to the center of the susceptor electrode. A plasma excitation electrode to which power for plasma excitation is supplied into a chamber for performing plasma treatment;
A susceptor electrode provided facing the plasma excitation electrode and into which a high-frequency current generated by the plasma excitation power flows after passing through the plasma space;
A susceptor shield provided around the susceptor electrode and having the same potential as that of the chamber wall of the chamber chamber;
The plasma processing apparatus, wherein the chamber wall and the susceptor shield are short-circuited in an alternating manner.   The plasma processing apparatus according to claim 7, wherein the chamber wall and the susceptor shield are electrically connected.   9. The plasma according to claim 7, wherein a point on the chamber side that short-circuits the susceptor shield and the chamber wall is in a range of less than 500 mm in a horizontal direction from a side wall of the chamber chamber. Processing equipment.   10. The plasma processing apparatus according to claim 9, wherein each point where the susceptor shield and the chamber wall are short-circuited is within a range of less than 500 mm in a horizontal direction from a side wall of the chamber chamber.   9. The plasma processing apparatus according to claim 7, wherein the chamber wall and the susceptor shield are short-circuited at a plurality of points.   12. The plasma processing apparatus according to claim 11, wherein a short-circuit point for short-circuiting the chamber wall and the susceptor shield is substantially point symmetric with respect to the center of the susceptor electrode.

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