KR100724195B1 - Plasma etching apparatus for semiconductor devices - Google Patents

Abstract

The present invention relates to a semiconductor device plasma etching apparatus. That is, in the present invention, in the semiconductor device plasma etching apparatus, a dual gas supply line is formed on the upper electrode of the etching apparatus so that different gases can be supplied to the center region and the wafer edge region where the semiconductor element is formed. When etching the electrode film or IMD film, the same gas is supplied to the inner / outer gas supply line on the electrode, and during the bevel etching of the wafer edge area, the residual electrode film and the IMD film are etched by the outer gas supply line on the wafer edge area. By supplying a plasma gas different from the inner gas supply line for the gas, and adjusting the gap between the upper electrode and the lower cathode to be narrowed within a certain range, the etching speed in the center region of the wafer is significantly lowered, thereby increasing the etching selectivity in the edge region. Bevel etching process without additional photoresist film process To enable.

Plasma, Etch, Wafer, Bevel Etch, Photoresist

Description

Plasma Etching Device of Semiconductor Device {PLASMA ETCHING APPARATUS FOR SEMICONDUCTOR DEVICES}

1 is a configuration of a plasma etching apparatus having a dual gas supply line according to an embodiment of the present invention,

2 is a block diagram of a plasma etching apparatus of a semiconductor device according to another embodiment of the present invention.

<Brief description of the major symbols in the drawings>

100: control unit 102: drive unit

104: cathode electrode 106: wafer

108: upper electrode 110: outer gas supply line

112: inner gas supply line 114: edge area

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma etch apparatus of a semiconductor device. In particular, a semiconductor device capable of bevel etching without a photo-resist layer process using a binary gas supply line is provided. The present invention relates to a plasma etching apparatus.

In general, a semiconductor device is formed by repeatedly depositing and patterning a thin film on a wafer, patterning, and ion implantation processes several times. In particular, in order to manufacture integrated circuit devices, a multilayer thin film is used. A process of stacking the photoresist, forming and patterning a photoresist film on each thin film, and etching the thin film by using the patterned photoresist as a mask several times.

In the process of stacking and patterning a thin film many times on the wafer surface as described above, several films are also deposited on the edge of the wafer, resulting in a thicker edge of the wafer or unnecessary films on the sidewalls of the wafer. It acts as a particle source and causes defects.

Therefore, in the related art, a bevel etching process is performed to remove unnecessary films deposited in the wafer edge region according to a plurality of semiconductor processes, thereby preventing the deposited films from acting as particle sources on the wafer edge region.

However, in the case of the bevel etching process performed in the conventional semiconductor device fabrication, a mask is formed on the semiconductor element formation region except for the edge portion on the wafer, and then deposited on the wafer edge region by wet or dry etching the wafer edge region. The unnecessary films were removed, and the photoresist film process for bevel etching was additionally performed.

Accordingly, an object of the present invention is to provide a semiconductor device plasma etching apparatus capable of bevel etching without a photoresist film process using a binary gas supply line.

The present invention for achieving the above object is a semiconductor device plasma etching apparatus capable of bevel etching without a photo process using a binary gas supply line, supplying a binary gas for IMD film etching and bevel etching for forming a pattern on a wafer An upper electrode on which a line is formed, a cathode electrode on which a wafer is fixed below the upper electrode, and an upper electrode and a cathode by driving the cathode electrode up / down for adjusting an etching selectivity in the wafer edge region during the bevel etching A driving unit for controlling the gap and supplying the plasma gas for etching the residual IMD film to the outer gas supply line of the wafer edge region on the upper electrode during the bevel etching, and to the inner gas supply line of the wafer central region on the upper electrode. Is a corresponding plasma for increasing the etch selectivity in the edge region. The is characterized in that a control unit for supply.

Hereinafter, with reference to the accompanying drawings will be described in detail the operation of the preferred embodiment according to the present invention.

FIG. 1 illustrates dualization of a gas supply line of an upper electrode inside and an outer side of a plasma etching apparatus according to an exemplary embodiment of the present invention to control gas supplied to each other and simultaneously up / down a cathode electrode. A plasma etching apparatus is shown that enables the adjustment of the etching rate on a wafer through the gap adjustment to up / down.

Hereinafter, the bevel etching process for the wafer edge region 114 in which the photoresist film process is omitted in the plasma etching apparatus of the present invention which dualizes the gas supply line will be described in detail with reference to FIG. 1.

First, during the etching of the intermetal dielectric (IMD) film deposited on the wafer 106, the control unit 100 of the plasma etching apparatus is configured to perform the upper electrode 108 of the plasma etching apparatus under normal conditions for etching the IMD film. Both C5F8, O2 or C4F8, O2, and CO mixed gas are supplied to the gas supply lines 112 and 110 on the inner and outer sides to realize phase dualization, thereby etching the IMD on the wafer.

In this case, the distance between the upper electrode 108 and the lower cathode electrode 104 is controlled by the driver 102 for driving up / down the electrostatic chuck cathode 104 on which the wafer is placed under the control of the controller 100. It is adjusted within the range of 10-40 mm.

Subsequently, after the patterning through the etching of the IMD film is completed while the gap between the upper electrode 108 and the lower cathode electrode 104 is adjusted within the range of 10 to 40 mm, the wafer is present in the wafer edge region 114. A bevel etching process is subsequently performed to remove residual IMD film.

At this time, in the present invention, the inner gas supply line 112 and the outer gas supply line 110, which are dualized on the upper electrode 108 of the plasma etching apparatus, are formed on the IMD film without a separate photoresist film process for the bevel etching process. Different plasma gases are supplied for etching. That is, N2 or Ar gas is injected through the inner gas supply line 112 on the upper electrode 108, and CF4, CHF3 or the same gas as the IMD film is etched through the outer gas supply line 110. Injection into the upper edge region 114.

In addition, the gap between the upper electrode 108 and the cathode electrode 104 is adjusted to increase the etch selectivity with respect to the wafer edge region 114, which is controlled by the driving unit 102 under the control of the controller 100. The cathode electrode 104 is adjusted in accordance with the up / down driving to be lowered in the range of 0.3 to 1 mm. As a result, the etching speed in the center region of the wafer is significantly lowered, thereby increasing the etching selectivity in the edge region 114.

FIG. 2 illustrates dualization of a gas supply line on an upper electrode of a plasma etching apparatus into an inner side and an outer side to control gas supplied to each other, and simultaneously up / down a cathode electrode according to another embodiment of the present invention. The plasma etching apparatus is configured to enable the adjustment of the etching rate on the wafer through the gap adjustment.

Hereinafter, the bevel etching process for the wafer edge region in which the photoresist film process is omitted in the plasma etching apparatus of the present invention which dualizes the gas supply line will be described in detail with reference to FIG. 2.

First, when etching an electrode material such as a poly-si or aluminum (Al) film on a wafer, the controller 200 may dualize the upper electrode 208 of the plasma etching apparatus under normal conditions for etching the electrode material. Both of the inner and outer gas supply lines 210 and 212 are implemented to supply Cl 2, HBr, or Cl 2, BCl 3 mixed gas to etch the electrode material on the wafer 206.

At this time, the gap distance between the upper electrode 208 and the lower cathode electrode 204 is a drive unit 202 for driving up / down the electrostatic chuck cathode electrode 204 on which the wafer 206 is placed under the control of the controller 200. Is controlled in the range of 10 to 40 mm, and the pressure is in the range of 4 to 50 mT depending on the material.

Subsequently, after the patterning through the etching of the electrode material on the wafer is completed, the gap between the upper electrode 208 and the lower cathode electrode 204 is adjusted within the range of 10 to 40 mm as described above. A bevel etching process for removing the residual electrode material material film 218 and the residual IMD film 216 is subsequently performed.

At this time, in the present invention, the inner gas supply line 210 and the outer gas supply line 212 are dualized on the upper electrode 204 of the plasma etching apparatus, and the residual electrode film 218 and the photoresist film process are not used during the bevel etching process. Different plasma gases are supplied to etch the IMD film 216.

That is, N2 or Ar is injected into the inner gas supply line 210 on the upper electrode 208 in the plasma etching apparatus, and different gases are injected into the outer gas supply line 212 in two steps. In the step, Cl2, HBr (or BC13) mixed gas is injected into the wafer edge region 214 through the outer gas supply line 212 to remove the residual electrode film 218 on the wafer 206. 218) is removed.

Then, in step 2, a CF-based gas such as CF4 or CHF3 is injected into the wafer edge region 214 to remove the residual IMD film 216, and the etch selectivity with respect to the wafer edge region 214 is adjusted. In order to increase the gap between the upper electrode 208 and the lower cathode electrode 204 is adjusted, the gap is adjusted according to the driving up / down of the cathode electrode 204 of the drive unit 202 under the control of the controller 200 The gap between the electrode 208 and the lower cathode electrode 204 is adjusted to be lowered in the range of 0.3 to 1 mm. As a result, the etching speed in the center region of the wafer is significantly lowered, thereby increasing the etching selectivity in the edge region 214.

As described above, in the semiconductor device plasma etching apparatus, pattern formation is realized by implementing a dual gas supply line on the upper electrode of the etching apparatus so that different gases can be supplied to the wafer center region and the wafer edge region where the semiconductor element is formed. When etching the electrode film or IMD film, the same gas is supplied to the inner / outer gas supply line on the electrode, and when the bevel etching to the wafer edge area, the remaining electrode film and the IMD film are transferred to the outer gas supply line on the wafer edge area. It supplies plasma gas different from the inner gas supply line for etching, and adjusts the gap between the upper electrode and the lower cathode electrode to be narrowed within a certain range, thereby significantly reducing the etching speed of the center region of the wafer, thereby increasing the etching selectivity in the edge region. Bevel formula without additional photoresist process Allow each process to be carried out.

Meanwhile, in the above description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the invention should be defined by the claims rather than by the described embodiments.

As described above, in the present invention, in the semiconductor device plasma etching apparatus, by implementing a dual gas supply line on the upper electrode of the etching apparatus to supply different gases to the center region and the wafer edge region where the semiconductor element is formed When etching the electrode film or IMD film for pattern formation, the same gas is supplied to the inner and outer gas supply lines on the electrode, and when the bevel etching on the wafer edge area, the remaining electrode film and the outer gas supply line on the wafer edge area Supplying plasma gas different from the inner gas supply line for etching the IMD film, and adjusting the gap between the upper electrode and the lower cathode to be narrowed within a certain range, thereby significantly reducing the etching speed of the wafer center region, thereby reducing the etching selectivity in the edge region. By increasing the There is an advantage in that it is possible to perform the bevel etching process.

Claims (13)

A semiconductor device plasma etching apparatus capable of bevel etching without a photo process using a binary gas supply line, An upper electrode on which a dual gas supply line for IMD film etching and bevel etching is formed; A cathode electrode to which the wafer is fixed below the upper electrode; A driving unit for controlling the gap between the upper electrode and the cathode by driving the cathode electrode up / down to adjust the etching selectivity at the wafer edge during the bevel etching; When the bevel etching, the plasma gas for etching the residual IMD film is supplied to the outer gas supply line of the wafer edge region on the upper electrode, and the etching of the edge region is selected as the inner gas supply line of the center region of the wafer on the upper electrode. Control unit for supplying the corresponding plasma gas to increase the rain Semiconductor device plasma etching apparatus comprising a. The method of claim 1, The plasma gas for etching the residual IMD film is a semiconductor device plasma etching apparatus, characterized in that the CF4, CHF3 or C5F8, O2 / C4F8, O2, CO mixed gas. The method of claim 1, The corresponding plasma gas for increasing the etching selectivity is N2 or Ar gas, the semiconductor element plasma etching apparatus. The method of claim 1, The gap between the upper electrode and the lower cathode electrode for increasing the etching selectivity in the wafer edge region is adjusted to a range of 0.3 to 1mm. The method of claim 1, In the IMD film etching for forming the pattern on the wafer, the semiconductor device plasma etching apparatus characterized in that both C5F8, O2 or C4F8, O2, CO mixed gas is supplied to the inner / outer gas supply line on the upper electrode. The method of claim 5, The semiconductor device plasma etching apparatus of claim 1, wherein the gap between the upper electrode and the lower cathode electrode is adjusted in a range of 10 to 40 mm. A semiconductor device plasma etching apparatus capable of bevel etching without a photo process using a binary gas supply line, An upper electrode on which a dual gas supply line is formed for etching an electrode film and bevel etching on a wafer; A cathode electrode fixed with a wafer under the upper electrode; A driving unit which controls the gap between the upper electrode and the cathode by driving up / down of the cathode electrode for adjusting an etching selectivity in the wafer edge region during the bevel etching; During the bevel etching, different plasma gases for residual electrode film etching and IMD film etching are sequentially supplied to the outer gas supply line of the wafer edge region on the upper electrode, and to the inner gas supply line of the wafer central region on the upper electrode. The control unit for supplying a corresponding plasma gas for increasing the etching selectivity in the edge area Semiconductor device plasma etching apparatus comprising a. The method of claim 7, wherein The plasma gas for etching the residual electrode film is a semiconductor device plasma etching apparatus, characterized in that the mixed gas Cl2, HBr or Cl2, BCl3. The method of claim 7, wherein The plasma gas for etching the residual IMD film is a semiconductor device plasma etching apparatus, characterized in that the CF4, CHF3 or C5F8, O2 / C4F8, O2, CO mixed gas. The method of claim 7, wherein The gap between the upper electrode and the lower cathode electrode for increasing the etching selectivity in the wafer edge region is adjusted to a range of 0.3 to 1mm. The method of claim 7, wherein The corresponding plasma gas for increasing the etching selectivity is N2 or Ar gas, the semiconductor element plasma etching apparatus. The method of claim 7, wherein In the etching of the electrode film for forming the pattern on the wafer, the semiconductor device plasma etching apparatus characterized in that both the Cl2, HBr or Cl2, BCl3 mixed gas is supplied to the inner / outer gas supply line on the upper electrode. The method of claim 12, In the etching of the electrode film, the gap between the upper electrode and the lower cathode electrode, the semiconductor device plasma etching apparatus, characterized in that the pressure is adjusted to the range of 10 to 40mm, the pressure is adjusted to 4 ~ 50mT range.

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