Plasma Processing Equipment

Abstract

To provide a plasma processing apparatus having an embedded member that prevents abnormal discharge in a hole through which a heat transfer gas is passed.SOLUTION: A plasma processing apparatus a dielectric member having a mounting surface on which an object to be processed is mounted and a back surface with respect to the mounting surface, and having a first through hole penetrating the mounting surface and the back surface, a mounting table having a support surface that supports the dielectric member and having a base having a second through hole communicating with the first through hole, and an embedding member arranged inside the first through hole and the second through hole, the embedding member includes a first embedding member arranged in the first through hole and a second embedding member arranged in the second through hole, and the second embedding member has lower rigidity than the first embedding member.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a plasma processing apparatus. [Background technology]

[0002] Conventionally, there has been known a plasma processing apparatus that performs an etching process or the like on a workpiece such as a wafer using plasma (see, for example, Patent Document 1). Such a plasma processing apparatus has, for example, a mounting table that holds the workpiece and also serves as an electrode in a processing vessel that can form a vacuum space. The mounting table has a through hole (penetrating hole) formed therein for supplying a heat transfer gas between the back surface of the workpiece placed on the mounting table and the upper surface of the mounting table. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-195935 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, in plasma processing apparatuses, the high frequency power applied to the mounting table for plasma processing has been increased in voltage. When the high frequency power applied to the mounting table is increased in voltage, the energy of the high frequency power may concentrate in the through hole for supplying the heat transfer gas, causing abnormal discharge. If abnormal discharge occurs in the through hole for supplying the heat transfer gas, it may deteriorate the quality of the workpiece processed in the plasma processing apparatus and cause a decrease in the yield.

[0005] In response to the above-mentioned problems, in one aspect, the present invention has an object to provide a plasma processing apparatus having an embedded member that prevents abnormal discharge in a passage hole for a heat transfer gas. [Means for solving the problem]

[0006] In order to solve the above problem, according to one aspect, a mounting table includes a dielectric member having a mounting surface on which a workpiece is placed and a back surface opposite to the mounting surface, and in which a first through hole is formed penetrating the mounting surface and the back surface, and a base having a support surface for supporting the dielectric member and in which a second through hole communicating with the first through hole is formed, and an embedding member disposed inside the first through hole and the second through hole, the embedding member having a first embedding member disposed in the first through hole and a second embedding member disposed in the second through hole, the second embedding member having a rigidity lower than that of the first embedding member. and contacts the inner circumferential surface of the second through hole by a restoring force. A plasma processing apparatus is provided. Effect of the Invention

[0007] According to one aspect, it is possible to provide a plasma processing apparatus having an embedded member that prevents abnormal discharge in a passage hole for a heat transfer gas. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic cross-sectional view showing an example of the configuration of a plasma processing apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a schematic cross-sectional view illustrating an example of a mounting table according to the first embodiment. [Diagram 3] FIG. 13 is a schematic cross-sectional view illustrating a mounting table according to a reference example. [Figure 4] FIG. 13 is a schematic cross-sectional view illustrating a mounting table of a reference example during thermal expansion. [Diagram 5] FIG. 4 is a schematic cross-sectional view illustrating an example of the mounting table according to the first embodiment during thermal expansion. [Figure 6] FIG. 4 is a schematic cross-sectional view illustrating another example of the mounting table according to the first embodiment. [Figure 7] FIG. 11 is a schematic cross-sectional view illustrating an example of a mounting table according to a second embodiment. [Figure 8] FIG. 11 is a schematic cross-sectional view illustrating another example of the mounting table according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this specification and the drawings, substantially the same components are designated by the same reference numerals, and redundant description will be omitted.

[0010] [Configuration of plasma processing device] FIG. 1 is a schematic cross-sectional view showing an example of the configuration of a plasma processing apparatus 100 according to a first embodiment. The plasma processing apparatus 100 has a processing vessel 1 that is airtight and electrically grounded. The processing vessel 1 is cylindrical and made of, for example, aluminum. The processing vessel 1 defines a processing space in which plasma is generated. A mounting table 2 that horizontally supports a semiconductor wafer (hereinafter simply referred to as a "wafer") W, which is a workpiece, is provided inside the processing vessel 1. The mounting table 2 has a base 2a and an electrostatic chuck (ESC) 6. The base 2a is made of a conductive metal, for example, aluminum, and functions as a lower electrode. The electrostatic chuck 6 is made of ceramics, for example, alumina, and functions to electrostatically attract the wafer W. The mounting table 2 is supported by a support table 4. The support table 4 is supported by a support member 3 made of, for example, quartz. An edge ring 5 made of, for example, silicon is provided on the upper outer periphery of the mounting table 2. Furthermore, within the processing vessel 1, a cylindrical inner wall member 3a made of, for example, quartz is provided so as to surround the periphery of the mounting table 2 and the support table 4.

[0011] A first RF power supply 10a is connected to the base 2a via a matching unit 11a, and a second RF power supply 10b is connected to the base 2a via a matching unit 11b. The first RF power supply 10a supplies high frequency power for generating plasma of a predetermined frequency to the base 2a of the mounting table 2. The second RF power supply 10b supplies high frequency power for attracting ions (for bias) of a predetermined frequency lower than the frequency of the first RF power supply 10a to the base 2a of the mounting table 2.

[0012] A shower head 16 functioning as an upper electrode is provided above the mounting table 2, facing and parallel to the mounting table 2. The shower head 16 and the mounting table 2 function as a pair of electrodes (upper electrode and lower electrode).

[0013] The electrostatic chuck 6 is configured by interposing an electrode 6a between insulators 6b, and the electrode 6a is connected to a DC power supply 12. When a DC voltage is applied to the electrode 6a from the DC power supply 12, the wafer W is attracted by Coulomb force.

[0014] A coolant flow path 2d is formed inside the mounting table 2, and a coolant inlet pipe 2b and a coolant outlet pipe 2c are connected to the coolant flow path 2d. An appropriate coolant, for example, cooling water, is circulated through the coolant flow path 2d to control the mounting table 2 to a predetermined temperature. A gas supply pipe 210 is provided to pass through the mounting table 2 and the like, for supplying a gas for transferring cold heat (hereinafter, also referred to as a "heat transfer gas"), such as helium gas, to the rear surface of the wafer W, and the gas supply pipe 210 is connected to a heat transfer gas supply unit 31. With these configurations, the wafer W on the mounting table 2 is controlled to a predetermined temperature. The internal structure of the gas supply pipe 210 will be described later.

[0015] The mounting table 2 is provided with a plurality of, for example, three pin through holes 200 (only one is shown in FIG. 1), and a lifter pin 61 is disposed inside each of these pin through holes 200. The lifter pin 61 is connected to a drive mechanism 62 and is moved up and down by the drive mechanism 62.

[0016] The shower head 16 described above is provided on the ceiling wall of the processing vessel 1. The shower head 16 includes a main body 16a and an upper top plate 16b serving as an electrode plate, and is supported on the upper part of the processing vessel 1 via an insulating member 95. The main body 16a is made of a conductive material, for example, aluminum whose surface is anodized, and detachably supports the upper top plate 16b below it.

[0017] The main body 16a is provided with a gas diffusion chamber 16c inside. The main body 16a is provided with a number of gas flow holes 16d at the bottom so as to be located below the gas diffusion chamber 16c. The upper top plate 16b is provided with a gas introduction hole 16e penetrating in the thickness direction, and the gas introduction hole 16e is provided so as to communicate with the gas flow hole 16d.

[0018] The body 16a is provided with a gas inlet 16g for introducing a processing gas into the gas diffusion chamber 16c. One end of a gas supply pipe 15a is connected to the gas inlet 16g. The other end of the gas supply pipe 15a is connected to a gas supply unit 15 for supplying a processing gas. The gas supply pipe 15a is provided with a mass flow controller (MFC) 15b and an on-off valve V2 in this order from the upstream side. The gas supply unit 15 supplies a processing gas for plasma etching to the gas diffusion chamber 16c through the gas supply pipe 15a. With this configuration, the processing gas supplied to the gas diffusion chamber 16c is dispersed in a shower-like manner and supplied into the processing vessel 1 through the gas flow holes 16d and the gas introduction holes 16e.

[0019] A variable DC power supply 72 is electrically connected to the shower head 16 serving as the upper electrode via a low pass filter (LPF) 71. The variable DC power supply 72 can be turned on and off by an on-off switch 73. The current and voltage of the variable DC power supply 72 and the on-off of the on-off switch 73 are controlled by a control unit 90. When radio frequency (RF) is applied to the mounting table 2 from the first RF power supply 10a and the second RF power supply 10b to generate plasma in the processing space, the control unit 90 turns on the on-off switch 73 as necessary, and a predetermined DC voltage is applied to the shower head 16.

[0020] A cylindrical ground conductor 1a is provided so as to extend from the side wall of the processing vessel 1 to a position above the height position of the shower head 16. This cylindrical ground conductor 1a has a ceiling wall on its upper portion.

[0021] An exhaust port 81 is formed at the bottom of the processing vessel 1. An exhaust device 83 is connected to the exhaust port 81 via an exhaust pipe 82. The exhaust device 83 has a vacuum pump, and the inside of the processing vessel 1 is depressurized to a predetermined vacuum level by operating this vacuum pump. A loading / unloading port 84 for the wafer W is provided at a side wall inside the processing vessel 1, and a gate valve 85 for opening and closing the loading / unloading port 84 is provided at the loading / unloading port 84.

[0022] A deposit shield 86 is provided along the inner wall surface on the inside of the side of the processing vessel 1. The deposit shield 86 prevents etching by-products (deposits) from adhering to the processing vessel 1. A conductive member (GND block) 89 connected to a ground potential in a controllable manner is provided at approximately the same height as the wafer W on the deposit shield 86, thereby preventing abnormal discharge. In addition, a deposit shield 87 extending along the inner wall member 3a is provided at the lower end of the deposit shield 86. The deposit shields 86, 87 are detachable.

[0023] The operation of the plasma processing apparatus 100 having the above configuration is generally controlled by a control unit 90. The control unit 90 is provided with a CPU 91 that controls each unit of the plasma processing apparatus 100, an interface 92, and a memory 93.

[0024] The interface 92 is composed of a keyboard through which a process manager inputs commands for managing the plasma processing apparatus 100, a display that visualizes and displays the operating status of the plasma processing apparatus 100, and the like.

[0025] The memory 93 stores recipes in which control programs (software) and processing condition data are stored for implementing various processes executed by the plasma processing apparatus 100 under the control of the CPU 91. Then, as necessary, an arbitrary recipe is called from the memory 93 in response to an instruction or the like in response to an input operation from the interface 92 and executed by the CPU 91, whereby a desired process is performed in the plasma processing apparatus 100 under the control of the CPU 91. In addition, recipes such as the control programs and processing condition data can be used in a state stored in a computer-readable computer storage medium (e.g., a hard disk, a CD, a flexible disk, a semiconductor memory, etc.) or can be used online by transmitting them from another apparatus at any time, for example, via a dedicated line.

[0026] [Configuration of the mounting table of the first embodiment] An example of the configuration of the mounting table 2 according to the first embodiment will be described with reference to FIG. 2. FIG. 2 is an example of a schematic cross-sectional view showing the mounting table 2 according to the first embodiment. The mounting table 2 has a base 2a and an electrostatic chuck 6. As described above, the base 2a is made of a conductive metal (e.g., aluminum). The electrostatic chuck 6 is made of a ceramic (e.g., alumina) having plasma resistance. That is, the base 2a and the electrostatic chuck 6 are made of different materials. An edge ring 5 made of, for example, silicon is provided on the upper outer periphery of the mounting table 2.

[0027] The electrostatic chuck 6 is disk-shaped and has a mounting surface 21 for mounting a similarly disk-shaped wafer W thereon, and a back surface 22 facing the mounting surface 21. The base 2a has a support surface 23 for supporting the electrostatic chuck 6, and a back surface 24 facing the support surface 23. The back surface 22 of the electrostatic chuck 6 and the support surface 23 of the base 2a are joined to form an interface 25.

[0028] An end (gas hole) of a gas supply pipe 210 is formed in the mounting surface 21. The gas supply pipe 210 forms a through hole 211 and a through hole 212, and supplies a heat transfer gas such as helium gas to the back surface of the wafer W. The through hole 211 is provided so as to penetrate from the back surface 22 of the electrostatic chuck 6 to the mounting surface 21. That is, the inner wall of the through hole 211 is formed by the electrostatic chuck 6. On the other hand, the through hole 212 is provided so as to penetrate from the back surface 24 of the base 2a to the support surface 23. That is, the inner wall of the through hole 212 is formed by the base 2a (the inner peripheral surface of a gas sleeve 213 described later).

[0029] The through hole 211 is an example of a first through hole penetrating the mounting surface 21 on which the wafer W is mounted and the back surface 22 opposite to the mounting surface 21, and the through hole 212 is an example of a second through hole formed in the base 2a and communicating with the first through hole. The electrostatic chuck 6 is an example of a dielectric member in which a first through hole is formed. However, the dielectric member in which the first through hole is formed does not have to have the function of the electrostatic chuck 6.

[0030] The through hole 211 has a small diameter portion 211a, a step portion 211b, and a large diameter portion 211c. The small diameter portion 211a is a hole formed so that one end (upper end) opens to the placement surface 21. The large diameter portion 211c is a hole formed so that one end (lower end) opens to the rear surface 22. The hole diameter of the small diameter portion 211a is smaller than the hole diameter of the large diameter portion 211c. The other end (lower end) of the small diameter portion 211a is connected so as to communicate with the other end (upper end) of the large diameter portion 211c. In addition, a step portion 211b is formed at the connection portion between the small diameter portion 211a and the large diameter portion 211c, which have different hole diameters.

[0031] The diameter of the through hole 212 is equal to the diameter of the large diameter portion 211c (below the step portion 211b of the through hole 211). The through holes 211 and 212 are formed so that their positions coincide with each other at room temperature, for example. A gas sleeve 213 made of alumina is disposed in the gas supply pipe 210. A spacer may be provided on the inner wall of the gas supply pipe 210.

[0032] An embedding member 220 is disposed inside the gas supply pipe 210. The embedding member 220 has a first embedding member 221 disposed in the through hole 211 and a second embedding member 222 disposed in at least the through hole 212.

[0033] The first embedded member 221 is formed in a convex shape in cross section. That is, the first embedded member 221 has a small diameter portion 221a, a step portion 221b, and a large diameter portion 221c. The diameter of the small diameter portion 221a is smaller than the diameter of the large diameter portion 221c. In addition, a step portion 221b is formed at the connection portion between the small diameter portion 221a and the large diameter portion 221c, which have different diameters.

[0034] The diameter of the small diameter portion 221a of the first embedding member 221 is smaller than the hole diameter of the small diameter portion 211a of the through hole 211. The diameter of the large diameter portion 221c of the first embedding member 221 is larger than the hole diameter of the small diameter portion 211a of the through hole 211 and smaller than the hole diameter of the large diameter portion 211c of the through hole 211. As a result, the first embedding member 221 inserted into the through hole 211 from the back surface 22 side of the electrostatic chuck 6 cannot be pulled out to the mounting surface 21 side of the electrostatic chuck 6.

[0035] The first embedding member 221 is made of a plasma-resistant material such as ceramics. For example, the first embedding member 221 may be made of any of quartz, silicon carbide, silicon nitride, aluminum oxide, aluminum nitride, yttria, titanium oxide, and tungsten carbide.

[0036] The second embedded member 222 is disposed below the first embedded member 221. The second embedded member 222 is formed as a shaft member. The shaft diameter of the second embedded member 222 is equal to the large diameter portion 221c of the first embedded member 221. In addition, the shaft diameter of the second embedded member 222 is formed smaller than the large diameter portion 211c of the through hole 211 and the hole diameter of the through hole 212.

[0037] The second embedded member 222 is formed of a material (elastic material) having lower rigidity than the first embedded member 221. For example, it is formed of a fluororesin such as PTFE (polytetrafluoroethylene).

[0038] The axial length of the first embedding member 221 is shorter than the thickness of the electrostatic chuck 6 (the axial length of the through hole 211). Specifically, the axial length of the small diameter portion 221a of the first embedding member 221 is substantially equal to the axial length of the small diameter portion 211a of the through hole 211. The axial length of the large diameter portion 221c of the first embedding member 221 is shorter than the axial length of the large diameter portion 211c of the through hole 211.

[0039] The second embedding member 222 is disposed across the through hole 212 and the large diameter portion 211c of the through hole 211. That is, an interface 230 where the first embedding member 221 and the second embedding member 222 contact each other is disposed inside the through hole 211. In other words, the second embedding member 222 is disposed at a height position of an interface 25 between the back surface 22 of the electrostatic chuck 6 and the support surface 23 of the base 2a.

[0040] The diameter of the first embedded member 221 is smaller than the hole diameter of the through hole 211. The diameter of the second embedded member 222 is smaller than the hole diameter of the through hole 212. As a result, the first embedded member 221 and the second embedded member 222 are disposed at a predetermined interval from the inner wall of the gas supply pipe 210, and a heat transfer gas path is provided inside the through hole 211 and the through hole 212.

[0041] In the plasma processing apparatus 100, the high-frequency power applied to the mounting table 2 is increased in voltage. When the high-frequency power applied to the mounting table 2 is increased in voltage, abnormal discharge may occur near the through-hole 211.

[0042] That is, in the plasma processing apparatus 100, when high frequency power is applied to the mounting table 2, a potential difference occurs between the wafer W and the rear surface 22 of the electrostatic chuck 6 due to the electrostatic capacitance of the electrostatic chuck 6. When the potential difference of the RF potential generated in the through hole 211 exceeds a limit value at which a discharge occurs, an abnormal discharge occurs.

[0043] On the other hand, it is known that the occurrence of abnormal discharge can be prevented by shortening the distance that the charged particles of the heat transfer gas can travel in a straight line inside the through hole 211 based on Paschen's law. Therefore, in this embodiment, an embedding member 220 is disposed inside the gas supply pipe 210 to prevent the occurrence of abnormal discharge.

[0044] Here, the mounting table 2 according to the first embodiment will be further described in comparison with the mounting table 2 according to a reference example.

[0045] A mounting table 2 having an embedding member 320 according to a reference example will be described with reference to Fig. 3 and Fig. 4. Fig. 3 is an example of a schematic cross-sectional view showing the mounting table 2 of the reference example during thermal expansion.

[0046] The mounting table 2 of the reference example is formed with a gas supply pipe 310 instead of the gas supply pipe 210 (see FIG. 2). The gas supply pipe 310 has a through hole 311 and a through hole 312. The through hole 311 is provided so as to penetrate from the back surface 22 to the mounting surface 21 of the electrostatic chuck 6. The through hole 312 is provided so as to penetrate from the back surface 24 to the support surface 23 of the base 2a. The hole diameter of the through hole 311 is formed to be smaller than the hole diameter of the through hole 312.

[0047] Moreover, an embedding member 320 is disposed inside the gas supply pipe 310. The embedding member 320 includes a first embedding member 321 and a second embedding member 322.

[0048] The first embedding member 321 is formed in a convex shape in cross section. That is, the first embedding member 321 has a small diameter portion 321a, a step portion 321b, and a large diameter portion 321c. The diameter of the small diameter portion 321a is smaller than the diameter of the large diameter portion 321c. In addition, a step portion 321b is formed at the connection portion between the small diameter portion 321a and the large diameter portion 321c, which have different diameters.

[0049] The diameter of the small diameter portion 321a of the first embedding member 321 is smaller than the diameter of the through hole 311. The diameter of the large diameter portion 321c of the first embedding member 321 is larger than the diameter of the through hole 311 and smaller than the diameter of the through hole 312. As a result, the first embedding member 321 inserted into the gas supply pipe 310 (through holes 311, 312) from the back surface 24 side of the base 2a cannot be pulled out to the mounting surface 21 side of the electrostatic chuck 6.

[0050] The first embedded member 321 is made of a plasma-resistant material such as ceramics.

[0051] The second embedded member 322 is disposed below the first embedded member 321. The second embedded member 322 is formed as a shaft member. The shaft diameter of the second embedded member 322 is equal to the large diameter portion 321c of the first embedded member 321. In addition, the shaft diameter of the second embedded member 322 is formed smaller than the hole diameter of the through hole 312.

[0052] The second embedded member 322 is made of, for example, alumina.

[0053] The small diameter portion 321a of the first embedding member 321 is disposed at an interface 25 between the back surface 22 of the electrostatic chuck 6 and the support surface 23 of the base 2a. An interface 330 where the first embedding member 321 and the second embedding member 322 contact each other is disposed within the through hole 312.

[0054] The embedding member 320 according to the reference example is disposed at a predetermined distance from the inner wall of the gas supply pipe 310 .

[0055] Abnormal discharge in through hole 311 can be prevented by reducing the distance between embedding member 320 and through hole 311. Abnormal discharge in through hole 311 can also be prevented by shortening the straight portion of the heat transfer gas path. This is because the energy of electrons in the heat transfer gas can be reduced. Therefore, as shown in FIG. 3, it is conceivable to form the diameter of through hole 312 to be larger than the diameter of through hole 311, and to form the portion of embedding member 320 corresponding to through hole 312 to be thicker than the portion corresponding to through hole 311.

[0056] However, in this case, the embedding member 320 may be damaged. For example, the temperature of the mounting table 2 may become as high as 100° C. to 200° C. when plasma processing is performed. The electrostatic chuck 6 is made of ceramics, and the base 2a is made of metal, and they have different linear thermal expansion coefficients. Therefore, when the temperatures of the electrostatic chuck 6 and the base 2a become high, the difference in thermal expansion between the electrostatic chuck 6 and the base 2a causes a positional deviation between the through hole 311 and the through hole 312, as shown in FIG. 4 as an example. In this case, a shear stress is applied to the embedding member 320 from the base 2a. As a result, the portion of the embedding member 320 corresponding to the through hole 311 may come into contact with the electrostatic chuck 6, and the embedding member 320 may be damaged.

[0057] The mounting table 2 of the first embodiment during thermal expansion will be described with reference to Fig. 2 and Fig. 5. Fig. 5 is an example of a schematic cross-sectional view showing the mounting table 2 of the first embodiment during thermal expansion.

[0058] 2 and 5, in the embedding member 220 according to the first embodiment, a second embedding member 222 having a lower rigidity than the first embedding member 221 is disposed below a first embedding member 221 having plasma resistance. The first embedding member 221 and the second embedding member 222 are in contact with each other inside the electrostatic chuck 6 (inside the through hole 211). In other words, an interface 230 between the first embedding member 221 and the second embedding member 222 is provided above an interface 25 between the electrostatic chuck 6 and the base 2a (on the side of the mounting surface 21 of the electrostatic chuck 6).

[0059] 5, when the positions of the through holes 211 and 212 are misaligned due to thermal expansion, a shear stress is applied to the embedding member 220 from the base 2a. In this case, in the mounting table 2 of the first embodiment, the shear stress is received by the second embedding member 222, which has low rigidity, and the second embedding member 222 is deformed, thereby preventing damage to the embedding member 220.

[0060] Furthermore, by disposing the embedding member 220 in the gas supply pipe 210, it is possible to prevent abnormal discharge from occurring in the through hole 211 due to high-frequency power applied to the base 2 a while sufficiently supplying heat transfer gas to the back surface of the wafer W.

[0061] 1, the inside of the processing vessel 1 is also evacuated to the processing space side by the exhaust device 83. If the wafer W is not placed on the electrostatic chuck 6, the first embedding member 221 is not fixed to the second embedding member 222 and may jump out of the through hole 211 into the processing space above the electrostatic chuck 6.

[0062] Therefore, the first embedding member 221 according to the first embodiment has a step portion 221b, and is shaped so that the diameter below the step portion 221b is larger than the diameter above the step portion 221b. This can prevent the first embedding member 221 from scattering into the processing space when the processing vessel 1 is evacuated or when a heat transfer gas is supplied to the rear surface of the wafer W.

[0063] Note that the first embedded member 221 is not limited to a convex shape, and as described above, may have any shape that has a portion that is wider below than the width of the upper end of the first embedded member 221. With such a shape, the first embedded member 221 can be prevented from protruding from the gas supply pipe 210.

[0064] [Other Configurations of the Mounting Table of the First Embodiment] Another example of the configuration of the mounting table 2 according to the first embodiment will be described with reference to Fig. 6. Fig. 6 is a schematic cross-sectional view showing another example of the mounting table 2 according to the first embodiment.

[0065] The gas supply pipe 210 forms a through hole 211 and a through hole 212. The through hole 211 is provided so as to penetrate from the back surface 22 to the mounting surface 21 of the electrostatic chuck 6. The through hole 211 has a truncated cone portion 211d and a cylindrical portion 211e. The truncated cone portion 211d is a hole formed so that one end (upper end) opens to the mounting surface 21. The cylindrical portion 211e is a hole formed so that one end (lower end) opens to the back surface 22. The truncated cone portion 211d expands in diameter from one end (upper end) to the other end (lower end). The other end (lower end) of the truncated cone portion 211d is connected so as to communicate with the other end (upper end) of the cylindrical portion 211e. The through hole 312 is similar to the through hole 312 shown in FIG. 2, and a duplicated description will be omitted.

[0066] Further, an embedding member 220 is disposed inside the gas supply pipe 210. The embedding member 220 has a first embedding member 221 and a second embedding member 222. The first embedding member 221 is formed in a trapezoidal truncated cone shape (approximately a triangle with a flat top) in cross section. The first embedding member 221 is formed so as to expand in diameter from the top surface toward the bottom surface. The first embedding member 221 is formed of a material such as ceramics having plasma resistance. The second embedding member 222 is similar to the second embedding member 222 shown in FIG. 2, and a duplicated description will be omitted.

[0067] The shape of the first embedded member 221 is not limited to the shapes shown in Fig. 2 and Fig. 6. The shape of the first embedded member 221 is not limited to this as long as it has a portion that is wider on the lower side than the width of the upper end portion.

[0068] [Configuration of the mounting table according to the second embodiment] Next, an example of the configuration of the mounting table 2 according to the second embodiment will be described with reference to Fig. 7 and Fig. 8. Fig. 7 is an example of a schematic cross-sectional view showing the mounting table 2 according to the second embodiment. Fig. 8 is another example of a schematic cross-sectional view showing the mounting table 2 according to the second embodiment.

[0069] The mounting table 2 of the second embodiment includes a base 2a and an electrostatic chuck 6, similar to the mounting table 2 of the first embodiment (see FIG. 2). The gas supply pipe 210 has a through hole 211 and a through hole 212. The through hole 211 is provided so as to penetrate from the back surface 22 to the mounting surface 21 of the electrostatic chuck 6. The through hole 212 is provided so as to penetrate from the back surface 24 to the support surface 23 of the base 2a. The embedding member 220 is disposed inside the gas supply pipe 210. The embedding member 220 includes a first embedding member 221 and a second embedding member 222. The first embedding member 221 is formed of a material such as ceramics having plasma resistance. The second embedding member 222 is formed of a material having a lower rigidity (elastic material) than the first embedding member 221. In addition, the first embedded member 221 has a shape having a portion that is wider on the lower side than the width of the upper end portion, thereby preventing the first embedded member 221 from jumping out of the gas supply pipe 210 due to the flow of the heat transfer gas.

[0070] The embedding member 220 is inserted into the through holes 211, 212 from the rear surface 24 side of the base 2a. Here, the outer diameter of the embedding member 220 is designed to be slightly smaller than the inner diameter of the through holes 211, 212 so that the embedding member 220 can be smoothly inserted to the depths of the through holes 211, 212. However, if the inner diameters of the through holes 211, 212 are large and the outer diameter of the embedding member 220 is small within the range of tolerance, the embedding member 220 may fall from the mounting table 2. For example, when the mounting table 2 is attached to an apparatus with the embedding member 220 inserted in the through holes 211, 212, the embedding member 220 may fall and be damaged. On the other hand, if the embedding member 220 is prevented from falling by strictly controlling the tolerance, the cost may increase.

[0071] In contrast to this, in the mounting table 2 of the second embodiment, the second embedding member 222 is structured to generate a slight force in the lateral direction (radial direction) to the through hole 212. In other words, the second embedding member 222 is elastically deformed to be inserted into the through hole 212, and is configured to press the inner circumferential surface of the through hole 212 by the restoring force of the second embedding member 222.

[0072] For example, in the mounting table 2 shown in FIG. 7, the second embedding member 222 has a notch at the bottom and is bifurcated so as to spread outward. When the embedding member 220 is inserted into the through holes 211 and 212, the bottom of the second embedding member 222 spreading outward comes into contact with the inner circumferential surface of the through hole 212 to generate frictional force, thereby preventing the embedding member 220 from falling. In addition, by bringing the outer circumferential surface of the second embedding member 222 into partial contact with the inner circumferential surface of the through hole 212 to reduce frictional force, the embedding member 220 can be smoothly inserted to the depths of the through holes 211 and 212 when the embedding member 220 is inserted into the through holes 211 and 212. The bottom of the second embedding member 222 may be branched into three or more parts.

[0073] 8, the second embedding member 222 has a curved shape. When the embedding member 220 is inserted into the through holes 211, 212, the second embedding member 222 expanding outward comes into partial contact with the inner circumferential surface of the through hole 212 to generate frictional force, thereby preventing the embedding member 220 from falling off. In addition, by bringing the outer circumferential surface of the second embedding member 222 into partial contact with the inner circumferential surface of the through hole 212 to reduce the frictional force, the embedding member 220 can be smoothly inserted to the depths of the through holes 211, 212 when the embedding member 220 is inserted into the through holes 211, 212.

[0074] The second embedding member 222 shown in FIG. 7 or FIG. 8 may be applied to the mounting table 2 (see FIGS. 2 and 6) of the first embodiment.

[0075] Although the method for manufacturing the plasma processing apparatus and the mounting table has been described above with reference to the above embodiment, the method for manufacturing the plasma processing apparatus and the mounting table according to the present invention is not limited to the above embodiment, and various modifications and improvements are possible within the scope of the present invention. The items described in the above embodiments can be combined to the extent that they are not inconsistent.

[0076] The interface 230 between the first embedding member 221 and the second embedding member 222 has been described as being within the electrostatic chuck 6 (above the interface 25 between the electrostatic chuck 6 and the base 2a), but is not limited to this. The interface 230 between the first embedding member 221 and the second embedding member 222 may be configured to be disposed below the interface 25 between the electrostatic chuck 6 and the base 2a. In this case, the shear stress from the base 2a due to thermal expansion is received by the large diameter portion 221c of the first embedding member 221. This makes it possible to prevent damage to the embedding member 220.

[0077] The plasma processing apparatus according to the present invention can be applied to any type of plasma processing apparatus, including Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Radial Line Slot Antenna, Electron Cyclotron Resonance Plasma (ECR), and Helicon Wave Plasma (HWP).

[0078] In this specification, the wafer W has been described as an example of an object to be processed in a plasma processing apparatus, but the object to be processed is not limited to this, and may be various substrates used in LCDs (Liquid Crystal Displays) and FPDs (Flat Panel Displays), CD substrates, printed circuit boards, etc. [Explanation of symbols]

[0079] W Wafer (processing object) 2. Placement table 2a base 6 Electrostatic chuck (dielectric material) 21 Placement surface 22 Back side 23 Support surface 24 Back side 25 Interface 100 Plasma treatment device 210 Gas supply pipe 211 through hole (first through hole) 212 Through hole (second through hole) 220 Embedded parts 221 First embedded member 221a small diameter portion (first cylindrical portion) 221b Step 221c Large diameter section (second cylindrical section) 222 Second embedded member 230 Interface

Claims

1. a dielectric member having a mounting surface on which an object to be processed is placed and a back surface opposite to the mounting surface, the dielectric member having a first through hole penetrating the mounting surface and the back surface; a mounting table having a support surface for supporting the dielectric member and a base having a second through hole formed therein and communicating with the first through hole; a filling member disposed inside the first through hole and the second through hole, the embedding member includes a first embedding member disposed in the first through hole, and a second embedding member disposed in the second through hole, the upper surface of the second embedding member being in contact with a lower surface of the first embedding member and the side surface of the second embedding member being in contact with a portion of an inner circumferential surface of the second through hole; the second embedding member has a lower rigidity than the first embedding member, and comes into contact with a part of an inner circumferential surface of the second through hole by a restoring force due to elastic deformation; Plasma processing equipment.

2. the first embedded member and the second embedded member are in contact with each other within the first through hole; The plasma processing apparatus according to claim 1 .

3. the first embedded member and the second embedded member are in contact with each other within the second through hole; The plasma processing apparatus according to claim 1 .

4. The first embedded member has a portion that is wider below the width of the upper end portion.

4. The plasma processing apparatus according to claim 1, wherein the first and second electrodes are disposed on the first and second surfaces of the substrate.

5. The width of the lower end of the first embedded member is equal to the width of the upper end of the second embedded member.

5. The plasma processing apparatus according to claim 1, wherein the first and second electrodes are disposed on the first and second surfaces of the substrate.

6. The first embedded member has a first columnar portion and a second columnar portion having a larger diameter than the first columnar portion. The plasma processing apparatus according to any one of claims 1 to 5.

7. The second embedded member has a notch at a lower portion and branches outwardly.

7. The plasma processing apparatus according to claim 1, wherein the first and second electrodes are disposed on the first and second surfaces of the substrate.

8. The second embedded member has a curved shape.

7. The plasma processing apparatus according to claim 1, wherein the first and second electrodes are disposed on the first and second surfaces of the substrate.

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