JP2008251860A - Silicon electrode plate for plasma etching - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silicon electrode plate for plasma etching in which only a few particles occur, even if a plasma etching is performed for a long time, and with which uniform etching can be performed. <P>SOLUTION: A silicon electrode substrate 1 comprises monocrystalline silicon, polycrystalline silicon or columnar crystalline silicon having a unidirectional coagulated configuration and is provided with a gas hole part inserting opening 2. A gas hole part 33 comprises silicon having a higher specific resistance than the silicon electrode substrate 1 and having a through pore 5 is fitted into the gas hole part inserting opening 2 of the silicon electrode substrate 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a silicon electrode plate for plasma etching that can generate uniform etching even when plasma etching is performed for a long time.

  Generally, when manufacturing a semiconductor integrated circuit, it is necessary to etch an interlayer insulating film formed on a silicon wafer. Plasma etching is performed to etch this silicon wafer with an interlayer insulating film (hereinafter referred to as a wafer). Silicon electrode plates are used. The silicon electrode plate 9 for plasma etching is a silicon electrode substrate 11 made of single crystal silicon, polycrystalline silicon, or columnar crystal silicon having a unidirectionally solidified structure, as shown in the schematic cross-sectional explanatory diagram of FIG. It has a structure in which through-holes 5 are provided in parallel to the thickness direction. The silicon electrode plate 9 for plasma etching is fixed at substantially the center in a vacuum vessel (not shown). On the other hand, the wafer 4 is placed on the gantry 6 and the etching gas 7 is passed through the through-hole 5 to the wafer 4. A plasma 8 is generated between the silicon electrode substrate 1 and the wafer 4 by applying a high-frequency voltage while flowing in the opposite direction, and this plasma 8 acts on the wafer 4 to etch the surface of the wafer 4.

  When the plasma etching operation of the wafer 4 is performed for a long time, the plasma etching silicon electrode plate 9 is also etched at the same time, and in particular, a part of the through-hole 5 provided parallel to the thickness direction of the silicon electrode substrate 11 As shown in FIG. 9 which is a cross-sectional explanatory view, the through-holes 5 on the surface in contact with the plasma are expanded and consumed so as to expand downward, and the degree of the consumption varies depending on the plasma concentration difference. The through-pores located in the central portion having the highest concentration are more exhausted than the through-pores located in the peripheral portion, so that the etching rate of the surface of the wafer 4 is not uniform between the central portion and the peripheral portion. In this phenomenon, the non-uniformity of the etching rate becomes more prominent as the plasma etching is performed for a longer time, and particularly when the density of the plasma 8 is kept uniform and the etching rate of the wafer 4 is required to be kept uniform. In this case, the time for using one silicon electrode plate 9 for plasma etching is limited to a very short time, and the plasma etching silicon electrode plate 9 must be replaced at an early stage even though the consumption amount of the silicon electrode plate 9 is small. Since the replaced silicon electrode plate 9 for plasma etching becomes scrap, it is used wastefully.

In order to solve this, as shown in the cross-sectional view of FIG. 5, a silicon electrode substrate 1 having a gas hole part insertion opening 2 is produced, and carbonization with less wear compared to silicon is made in the gas hole part insertion opening 2. A silicon electrode plate for plasma etching 10 shown in the cross-sectional view of FIG. 4 produced by fitting a gas hole part 3 having through-holes 5 made of silicon (SiC) is provided. When the silicon electrode plate 10 for plasma etching is used to etch a wafer, the through-hole 5 of the gas hole part 3 made of silicon carbide, which is much less consumed than silicon, is very little expanded and consumed. Therefore, it is said that the uniformity of the etching rate is ensured even if plasma etching is performed for a long time. As shown in FIG. 5, the gas hole part insertion opening 2 provided in the silicon electrode substrate 1 has a large diameter hole part 21 and a small diameter hole part 22, while the gas hole part 3 has a large diameter part 31, When the gas hole part 3 having the small diameter part 32 and the through hole 5 is fitted into the gas hole part insertion opening 2, the large diameter part 31 of the gas hole part 3 is inserted into the gas hole part. The small-diameter portion 32 of the gas hole part 3 is fitted into the small-diameter hole portion 22 of the gas hole part insertion opening 2 so as to fit into the large-diameter hole portion 21 of the opening 2. The gas hole part 3 is prevented from falling off when it is attached to the plasma etching apparatus.

Further, as shown in FIG. 6, the gas hole part insertion opening 2 provided in the silicon electrode substrate 1 has a taper extending upward, and the gas hole part insertion hole 2 is inserted into the gas hole part insertion opening 2 having this taper. A gas hole part made of silicon carbide having a taper opposite to that of the opening 2 is also known (see Patent Document 1).
JP 2004-79959 A

The silicon electrode plate for plasma etching 10 produced by fitting the gas hole part 3 made of silicon carbide having the through-holes 5 into the silicon electrode substrate 1 is certainly made of silicon carbide when the wafer is plasma etched using this. Since the through-hole 5 of the gas hole part is very little expanded and consumed, the etching uniformity is ensured even if plasma etching is performed for a long time. However, as shown in the partial sectional view of FIG. 7, when the sputtering is performed for a long time, the silicon electrode plate for plasma etching 10 produced by fitting the gas hole part 3 made of silicon carbide into the silicon electrode substrate 1 The silicon electrode substrate 1 is consumed so that the tip 12 of the gas hole part 3 protrudes from the lower surface of the silicon electrode substrate 1 because the consumption of the substrate 1 is large and the consumption of the gas hole parts made of silicon carbide is small. When the tip 12 of the gas hole part 3 is consumed so as to protrude from the lower surface of the silicon electrode substrate 1, a step is formed between the tip 12 and the silicon electrode substrate 1, and abnormal discharge occurs from this step, which is the cause. The silicon electrode plate for plasma etching 10 produced by fitting the gas hole part 3 made of conventional silicon carbide into the silicon electrode substrate 1 will generate many particles when used for a long time. Therefore, it cannot be used for a long time.

Accordingly, the present inventors have studied to obtain a silicon electrode plate for plasma etching that can generate uniform etching even when plasma etching is performed for a long time. as a result,
(A) Instead of the conventional gas hole part made of silicon carbide, as shown in the cross-sectional view of FIG. 1, the gas hole part 33 made of silicon larger than the specific resistance of the silicon electrode substrate 1 was fitted and produced. In the silicon electrode plate for plasma etching 10, the consumption rate of the gas hole part 33 made of silicon larger than the specific resistance of the silicon electrode substrate 1 is not significantly different from the consumption rate of the silicon electrode substrate 1. Compared with the silicon electrode plate 10 for plasma etching produced by fitting the gas hole part 3 made of silicon carbide into the silicon electrode substrate 1, the level difference generated between the gas hole part 3 and the silicon electrode substrate 1 is small. Even when plasma etching is performed for a long time, the generation of particles is reduced, and the resistivity is larger than the specific resistance of the silicon electrode substrate 1. And it becomes less able to expand depleted under broadening of the through pores 5 of the gas hole part 33 made of Con, the etching uniformity is improved,
(B) When the specific resistance of the silicon electrode substrate 1 is ρ, it is more preferable that the specific resistance ρ ′ of the gas hole part is in the range of 1.1ρ ≦ ρ ′ ≦ 1.5ρ. It was done.

The present invention has been made based on the results of such research,
(1) Plasma etching in which a gas hole part having a through hole made of silicon having a higher specific resistance than the silicon electrode substrate is inserted into a gas hole part insertion opening of a silicon electrode substrate provided with a gas hole part insertion opening. Silicon electrode plate,
(2) When the specific resistance value of the silicon electrode substrate provided with the gas hole part insertion opening is ρ and the specific resistance value of the gas hole part having the through hole is ρ ′, 1.1ρ ≦ ρ ′ ≦ 1. The silicon electrode plate for plasma etching according to the above (1) having a 5ρ relationship is characterized.

The silicon electrode substrate having the gas hole part insertion opening and the gas hole part having a through-hole are mainly made of single crystal silicon, but in addition to single crystal silicon, polycrystalline silicon or columnar crystal silicon having a unidirectionally solidified structure May consist of Therefore, the present invention
(3) The silicon electrode substrate for plasma etching according to (1) or 2, wherein each of the silicon electrode substrate having the gas hole part insertion opening and the gas hole part having a through hole is made of single crystal silicon,
(4) The silicon electrode plate for plasma etching according to (1) or 2, wherein each of the silicon electrode substrate having the gas hole part insertion opening and the gas hole part having a through hole is made of polycrystalline silicon,
(5) The silicon electrode for plasma etching according to (1) or 2 above, wherein each of the silicon electrode substrate having the gas hole part insertion opening and the gas hole part having a through hole is made of columnar crystal silicon having a unidirectionally solidified structure. It is characterized by a plate.

The silicon electrode plate for plasma etching according to the present invention only needs to have a specific resistance value larger than that of a silicon electrode substrate provided with a gas hole part insertion opening. When the specific resistance value of the silicon electrode substrate provided with the part insertion opening is ρ and the specific resistance value of the gas hole part having the through-hole is ρ ′, the relationship of 1.1ρ ≦ ρ ′ ≦ 1.5ρ is established. More preferably, it has. The reason is that if ρ ′ is smaller than 1.1ρ, the effect of suppressing the wear around the through-hole is not sufficient, and the conventional etching rate of the wafer is not uniform in the same manner as the electrode plate in the normal silicon. On the other hand, when ρ ′ is larger than 1.5ρ, the consumption rate of the gas hole part and the silicon electrode substrate is increased, and a large level difference is caused as in the case of the gas hole part made of silicon carbide. This is because the generation of particles and the generation of particles increase.

The silicon electrode plate for plasma etching according to the present invention shown in the cross-sectional view of FIG. 1 has a gas hole part insertion opening 2 having a large-diameter hole portion 21 and a small-diameter hole portion 22 as shown in the cross-sectional view of FIG. And a gas hole part 3 having a specific resistance value larger than that of the silicon electrode substrate 1 and having a large diameter part 31, a small diameter part 32, and a through-hole 5 are prepared. When the gas hole part 3 having the hole 5 is fitted into the gas hole part insertion opening 2, the large diameter part 31 of the gas hole part 3 is fitted into the large diameter hole part 21 of the gas hole part insertion opening 2. The small diameter portion 32 is made to fit into the small diameter hole portion 22 of the gas hole part insertion opening 2.
Further, in the silicon electrode plate for plasma etching according to the present invention, as shown in the sectional view of FIG. 2, the gas hole part insertion opening 2 provided in the silicon electrode substrate 1 has a taper extending upward, and this taper. A gas hole part composed of a gas hole part 34 made of silicon having a specific resistance larger than the specific resistance of the silicon electrode substrate 1 having a taper opposite to that of the gas hole part insertion opening 2. The thing fitted is also included.

For plasma etching in which a gas hole part having a through hole made of silicon having a higher specific resistance than that of the silicon electrode substrate is fitted into the gas hole part insertion opening of the silicon electrode substrate provided with the hole part insertion opening of the present invention. The silicon electrode plate does not cause non-uniformity in the etching rate of the wafer in a short period of time, unlike conventional electrode plates, even when used for a long time. Compared with the silicon electrode plate for plasma etching produced by being fitted to the electrode substrate, there are excellent effects such as no generation of particles.

Example 1
A single crystal silicon ingot having a specific resistance of 75 Ω · cm and a diameter of 300 mm is prepared, and the ingot is cut into a thickness of 6 mm by a diamond band saw, and a single crystal silicon electrode having a diameter of 280 mm and a thickness of 5 mm. A substrate was produced. In this single crystal silicon electrode substrate, as shown in FIG. 3, a gas hole part insertion opening 2 including a large diameter hole portion 21 having a diameter of 4 mm and a small diameter hole portion 22 having a diameter of 2 mm was formed.

  Further, a gas hole part having a large diameter portion 31 having a diameter of 4 mm and a small diameter portion 32 having a diameter of 2 mm is cut out from a single crystal silicon ingot having a specific resistance larger than that of the previous single crystal silicon electrode substrate: 90 Ω · cm. A through hole 5 having a diameter of 0.5 mm was formed in the gas hole part to produce a gas hole part 33 made of single crystal silicon. By inserting the gas hole part 33 into the gas hole part insertion opening 2, the silicon electrode plate for plasma etching of the present invention (hereinafter referred to as the present electrode plate) 1 was produced.

Furthermore, a sintered body having a large diameter portion 31 having a diameter of 4 mm and a small diameter portion 32 having a diameter of 2 mm is prepared by sintering silicon carbide powder having an average particle diameter of 5 μm. A gas hole part 3 made of silicon carbide is formed by forming a through-hole gas hole 5 of .5 mm, and this gas hole part 3 is fitted into the gas hole part opening 2 so that a conventional silicon electrode plate for plasma etching (hereinafter referred to as a gas electrode part 3). (Referred to as a conventional electrode plate).
Furthermore, the conventional electrode plate 2 was prepared by forming through-hole gas holes having a diameter of 0.5 mm at intervals of 8 mm on the single crystal silicon electrode substrate having a diameter of 280 mm and a thickness of 5 mm. .
Furthermore, a wafer having a diameter of 200 mm, on which a SiO ₂ layer was formed on the surface in advance by a CVD method, was prepared.

The electrode plate 1 of the present invention and the conventional electrode plates 1 and 2 are each set in a plasma etching apparatus, and a wafer on which a SiO ₂ layer is further formed is set in the plasma etching apparatus.
Chamber internal pressure: 10 ⁻¹ Torr,
Etching gas composition: 90 sccm CHF ₃ +4 sccm O ₂ +150 sccm He,
High frequency power: 2kW
Frequency: 20kHz,
Under the conditions, plasma etching of the SiO ₂ layer on the wafer surface was performed, and the number of particles generated immediately after the start of etching, after 500 hours from the start of etching, and after 700 hours had elapsed was counted. It was shown to. Further, the wafer is divided at 20 mm vertical and horizontal intervals, the etching amount of each area is measured, and the depth of the central portion etched most deeply: A and the depth of peripheral portion etched the shallowest: B are selected. Table 1 shows values obtained by substituting the measured values of B and B into the formula of (A−B) / B × 100 (%) (hereinafter referred to as etching rate difference), and evaluated the uniformity of plasma etching of the wafer. .

The results of plasma etching the SiO ₂ layer on the wafer surface using the electrode plate 1 of the present invention shown in Table 1 and the results of plasma etching the SiO ₂ layer on the wafer surface using the conventional electrode plates 1 and ₂ are compared. ,
(A) Etching in the case of plasma etching for 500 hours and 700 hours using the electrode plate 1 of the present invention is a value compared with the etching rate difference in the case of plasma etching for 500 hours and 700 hours using the conventional electrode plate 1 Therefore, both the electrode plate 1 of the present invention and the conventional electrode plate 1 can maintain a uniform etching rate difference for a long time, but the electrode plate 1 of the present invention can be sputtered for a longer time than the conventional electrode plate 1. You can see that the number of particles generated is small.
(B) Although the electrode plate 1 of the present invention generates less particles as in the case of the conventional electrode plate 2, the electrode plate 1 of the present invention has an etching rate when plasma etching is performed for 500 hours and 700 hours as compared with the conventional electrode plate 2. From the fact that the difference is small, it can be seen that the electrode plate 1 of the present invention can keep the etching rate difference uniform for a long period of time as compared with the conventional electrode plate 1.

Example 2
A polycrystalline silicon ingot having a specific resistance of 2 Ω · cm having a diameter of 300 mm is prepared by a melting / solidifying method, and this silicon ingot is cut with a diamond band saw, and then subjected to grinding and polishing to have a diameter of 280 mm and a thickness. A polycrystalline silicon electrode substrate having a size of 5 mm is prepared, and a gas comprising the large diameter hole portion 21 having a diameter of 4 mm and the small diameter hole portion 22 having a diameter of 2 mm shown in FIG. Hole part insertion opening 2 was formed.

  Further, a gas hole part having a large diameter portion 31 having a diameter of 4 mm and a small diameter portion 32 having a diameter of 2 mm is cut out from a polycrystalline silicon ingot having a specific resistance 3Ω · cm larger than that of the previous polycrystalline silicon electrode substrate. A through hole 5 having a diameter of 0.5 mm was formed in the gas hole part to produce a gas hole part 33 made of polycrystalline silicon. The electrode plate 2 of the present invention was manufactured by fitting the gas hole part 3 into the gas hole part insertion opening 2.

Further, the polycrystalline silicon electrode in which the gas hole part 3 made of silicon carbide produced in Example 1 is formed with the gas hole part insertion opening 2 made of the large diameter hole part 21 having a diameter of 4 mm and the small diameter hole part 22 having a diameter of 2 mm. A conventional electrode plate 3 was prepared by inserting into the gas hole part insertion opening 2 of the substrate.
Furthermore, the conventional electrode plate 4 was produced by forming through-holes having a diameter of 0.5 mm at intervals of 10 mm on the polycrystalline silicon electrode substrate having a diameter of 280 mm and a thickness of 5 mm.
Furthermore, a wafer having a diameter of 200 mm, on which a SiO ₂ layer was formed on the surface in advance by a CVD method, was prepared.

The electrode plate 2 of the present invention and the conventional electrode plates 3 to 4 are set in a plasma etching apparatus, and the wafer on which the SiO ₂ layer is formed is set in the plasma etching apparatus.
Chamber internal pressure: 10 ⁻¹ Torr,
Etching gas composition: 90 sccm CHF ₃ +4 sccm O ₂ +150 sccm He,
High frequency power: 2kW
Frequency: 20kHz,
Under the conditions, plasma etching of the SiO ₂ layer on the wafer surface was performed, and immediately after the start of etching, the number of particles generated at each time after the start of etching and after 500 hours from the start of etching and after 700 hours had elapsed was counted. Are shown in Table 2.
Further, the etching rate difference was determined in the same manner as in Example 1, and the results are shown in Table 2. The uniformity of plasma etching of the wafer was evaluated.

When using the present invention the electrode plate 2 shown in Table 2 compare the results of the SiO ₂ layer and plasma etching of the SiO ₂ layer of the wafer surface plasma etching result with using the conventional electrode plate 3-4 wafer surface ,
(C) The etching rate difference when plasma etching is performed for 500 hours and 700 hours using the electrode plate 2 of the present invention is different from the etching rate difference when plasma etching is performed using the conventional electrode plate 3 for 500 hours and 700 hours. Since the value is small, both the electrode plate 2 of the present invention and the conventional electrode plate 3 can maintain a uniform etching rate difference for a long time, but the electrode plate 2 of the present invention is sputtered for a longer time than the conventional electrode plate 3. But you can see that the number of particles generated is small,
(D) Although the electrode plate 2 of the present invention generates less particles as in the case of the conventional electrode plate 4, the electrode plate 2 of the present invention has an etching rate when plasma etching is performed for 500 hours and 700 hours compared to the conventional electrode plate 4. From the fact that the difference is small, it can be seen that the electrode plate 2 of the present invention can maintain a uniform etching rate difference over a long period of time as compared with the conventional electrode plate 4.

Example 3
A columnar silicon ingot having a specific resistance of 2 Ω · cm and a diameter of 300 mm is prepared, and this ingot is cut into pieces with a diamond band saw into a thickness of 6 mm, and the columnar crystal silicon having a diameter of 280 mm and a thickness of 5 mm. An electrode substrate was prepared, and a gas hole part insertion opening 2 composed of a large diameter hole portion 21 having a diameter of 4 mm and a small diameter hole portion 22 having a diameter of 2 mm shown in FIG. 3 was formed in this columnar crystal silicon electrode substrate.
Further, a gas hole part having a large diameter portion 31 having a diameter of 4 mm and a small diameter portion 32 having a diameter of 2 mm is cut out from a columnar silicon ingot having a specific resistance larger than that of the previous columnar crystal silicon electrode substrate: 3 Ω · cm. A through hole 5 having a diameter of 0.5 mm was formed in the gas hole part to produce a gas hole part 33 made of columnar crystal silicon. The electrode plate 3 of the present invention was produced by fitting the gas hole part 3 into the gas hole part insertion opening 2.

Furthermore, the columnar crystal silicon electrode in which the gas hole part 3 made of silicon carbide produced in Example 1 is formed with the gas hole part insertion opening 2 made of the large diameter hole part 21 having a diameter of 4 mm and the small diameter hole part 22 having a diameter of 2 mm. A conventional electrode plate 5 was produced by inserting it into the gas hole part insertion opening 2 of the substrate.

Furthermore, the conventional electrode plate 6 was prepared by forming through-holes having a diameter of 0.5 mm at intervals of 10 mm on the columnar crystal silicon electrode substrate having a diameter of 280 mm and a thickness of 5 mm.
Furthermore, a wafer having a diameter of 200 mm, on which a SiO ₂ layer was formed on the surface in advance by a CVD method, was prepared.

The electrode plate 3 of the present invention and the conventional electrode plates 5 to 6 are set in a plasma etching apparatus, and a wafer on which a SiO ₂ layer is formed is set in a plasma etching apparatus.
Chamber internal pressure: 10 ⁻¹ Torr,
Etching gas composition: 90 sccm CHF ₃ +4 sccm O ₂ +150 sccm He,
High frequency power: 2kW
Frequency: 20kHz,
Under the conditions, plasma etching of the SiO ₂ layer on the wafer surface was performed, and the number of particles generated at each time point immediately after the start of etching, after 500 hours from the start of etching, and after 700 hours had elapsed was counted. It was shown to.
Further, the etching rate difference was determined in the same manner as in Example 1, and the results are shown in Table 3 to evaluate the etching uniformity of the wafer.

When the SiO ₂ layer of the wafer surface using the results of the conventional electrode plate 5-6 of the SiO ₂ layer on the wafer surface was plasma etched using the present invention the electrode plate 3 shown in Table 3 to compare the results of the plasma etching ,
(E) The etching rate difference when plasma etching is performed for 500 hours and 700 hours using the electrode plate 3 of the present invention is different from the etching rate difference when plasma etching is performed using the conventional electrode plate 5 for 500 hours and 700 hours. Since the value is small, both the electrode plate 3 of the present invention and the conventional electrode plate 5 can maintain a uniform etching rate difference for a long time, but the electrode plate 3 of the present invention is sputtered for a longer time than the conventional electrode plate 5. But you can see that the number of particles generated is small,
(F) The electrode plate 3 of the present invention generates less particles as in the case of the conventional electrode plate 6, but the electrode plate 3 of the present invention has an etching rate when plasma etching is performed for 500 hours and 700 hours as compared with the conventional electrode plate 6. From the fact that the difference is small, it can be seen that the electrode plate 3 of the present invention can maintain a uniform etching rate difference over a long period of time compared to the conventional electrode plate 6.

It is a section explanatory view for explaining the silicon electrode plate for plasma etching of this invention. It is a section explanatory view for explaining the silicon electrode plate for plasma etching of this invention. FIG. 3 is a cross-sectional explanatory view for explaining the method of manufacturing the silicon electrode plate for plasma etching according to the present invention in FIG. 1. It is sectional explanatory drawing for demonstrating the conventional silicon electrode plate for plasma etching. FIG. 5 is a cross-sectional explanatory diagram for explaining a method of manufacturing the conventional plasma etching silicon electrode plate of FIG. 4. It is sectional explanatory drawing for demonstrating the conventional silicon electrode plate for plasma etching. FIG. 5 is a cross-sectional explanatory diagram for explaining a consumption state in a through-hole of the conventional silicon electrode plate for plasma etching of FIG. 4. It is a partial cross section schematic explanatory drawing for demonstrating the use condition of the conventional silicon electrode plate for plasma etching. It is sectional explanatory drawing for demonstrating the consumption state in the through-hole gas hole of the silicon electrode plate for conventional plasma etching.

Explanation of symbols

  1: Silicon electrode substrate, 2: Gas hole part insertion opening, 21: Large diameter hole part, 22: Small diameter hole part, 3: Gas hole part, 30: Gas hole part, 33: Gas hole part, 34: Gas hole part 4: wafer, 5: through-hole, 6: mount, 7: etching gas, 8: plasma, 9: conventional silicon electrode plate for plasma etching, 10: conventional silicon electrode plate for plasma etching, 11: silicon electrode Substrate, 12: tip,

Claims (5)

The gas hole part insertion opening of the silicon electrode substrate provided with the gas hole part insertion opening is fitted with a gas hole part having a through-hole made of silicon having a higher specific resistance than the silicon electrode substrate. Silicon electrode plate for plasma etching. When the specific resistance value of the silicon electrode substrate provided with the gas hole part insertion opening is ρ and the specific resistance value of the gas hole part having the through-hole is ρ ′, a relationship of 1.1ρ ≦ ρ ′ ≦ 1.5ρ The silicon electrode plate for plasma etching according to claim 1, comprising: 3. The silicon electrode plate for plasma etching according to claim 1, wherein both the silicon electrode substrate having the gas hole part insertion opening and the gas hole part having a through hole are made of single crystal silicon. 3. The silicon electrode plate for plasma etching according to claim 1, wherein the silicon electrode substrate having the gas hole part insertion opening and the gas hole part having a through-hole are both made of polycrystalline silicon. 3. The silicon for plasma etching according to claim 1, wherein the silicon electrode substrate having the gas hole part insertion opening and the gas hole part having a through-hole are made of columnar crystal silicon having a unidirectionally solidified structure. Electrode plate.

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