JP2016021434A - Stencil mask, plasma processing apparatus and plasma processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a desired pattern in an electrostatic chuck by easily conveying a mask onto the electrostatic chuck and disposing the mask thereon.SOLUTION: A stencil mask includes: a first mask with which the desired pattern is formed; a second mask which is disposed in an outer peripheral part of the first mask while being spaced apart from the first mask by a predetermined gap; and bridge members of which one end is connected with the first mask and the other end is connected with the second mask and which bridge the first and second masks at positions higher than the first and second masks. The first and second masks are bridged at three or more positions by the three or more bridge members and integrated.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a stencil mask, a plasma processing apparatus, and a plasma processing method.

  The plasma processing apparatus carries a plasma process in a state where a wafer is carried into a chamber and held on an electrostatic chuck. A pattern such as dots (hereinafter also referred to as “surface pattern”) is formed on the surface of the electrostatic chuck on which the wafer is placed. Since the surface pattern of the electrostatic chuck has an important function when controlling the temperature of the wafer, it is preferable that the surface pattern of the electrostatic chuck is optimized to various shapes depending on the target process. In order to change the surface pattern, it is necessary to design, optimize the pattern, and create a mask on which the optimized pattern is formed, and it takes a lot of cost and time.

  On the other hand, when using an electrostatic chuck with a built-in heater to accurately control the wafer temperature, the wafer temperature can be changed by changing the polishing condition of the surface of the electrostatic chuck and changing the contact area of the wafer. It has been done to control.

  Further, for example, in Patent Document 1, a film forming material is formed on an electrostatic chuck by disposing a mask composed of an outer ring-shaped body and a central body having a plurality of openings on the electrostatic chuck and performing a film forming process. An apparatus for making a wafer spacing mask on an electrostatic chuck is disclosed.

Japanese Patent Laid-Open No. 2001-20058

  However, in Patent Document 1, the outer ring-shaped body and the central body must be transported separately and placed separately on the electrostatic chuck. Therefore, the chamber must be opened to the atmosphere once before the outer ring-shaped body and the central body are placed on the electrostatic chuck. Therefore, the mask transport is complicated and the overall throughput is reduced.

  In addition, it is difficult to hold the outer ring-shaped body having an open center using pins that hold a wafer or the like placed on the electrostatic chuck. For this reason, it is necessary to newly install a member for holding the outer ring-shaped body and disposing it on the electrostatic chuck, which increases the cost.

  With respect to the above-described problem, an object of one aspect of the present invention is to form a desired pattern on an electrostatic chuck by easily transporting and arranging a mask on the electrostatic chuck.

  In order to solve the above problem, according to one aspect, a predetermined gap is formed between the first mask on which a desired pattern is formed and the outer periphery of the first mask with the first mask. The arranged second mask, one end is connected to the first mask, the other end is connected to the second mask, and the first and second masks are positioned higher than the first and second masks. A stencil mask having a bridge member for bridging a second mask, wherein the first and second masks are bridged and integrated at three or more locations by three or more bridge members. The

  According to one aspect, the mask can be easily transported and arranged on the electrostatic chuck, and a desired pattern can be formed on the electrostatic chuck.

The figure which shows the longitudinal cross-section of the plasma processing apparatus which concerns on one Embodiment. The figure which shows an example of a structure of the stencil mask which concerns on one Embodiment. The figure which shows an example of the pattern of the stencil mask which concerns on one Embodiment. The figure which shows the cross-sectional example of the pattern of the stencil mask which concerns on one Embodiment. The flowchart which shows an example of the plasma processing method which concerns on one Embodiment. The figure which shows notionally the plasma processing method of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In addition, in this specification and drawing, about the substantially same structure, the duplicate description is abbreviate | omitted by attaching | subjecting the same code | symbol.

[Overall configuration of plasma processing apparatus]
First, a plasma processing apparatus 1 according to an embodiment of the present invention will be described as an example. The plasma processing apparatus 1 is an apparatus that can form a desired pattern on the electrostatic chuck 106. In the plasma processing apparatus 1 according to the present embodiment, a mounting table 20 (lower electrode) and a gas shower head 25 (upper electrode) are disposed to face each other in a chamber 10, and gas is supplied from the gas shower head 25 into the chamber 10. This is a parallel plate type plasma processing apparatus.

  The plasma processing apparatus 1 includes a chamber 10 made of a conductive material such as aluminum and a gas supply source 15 that supplies a gas into the chamber 10. The chamber 10 is grounded. The gas supply source 15 supplies a specific gas to each of the film forming process, the etching process, and the waferless dry cleaning (WLDC) process of the pattern on the electrostatic chuck 106.

  In the chamber 10, a mounting table 20 for mounting a semiconductor wafer (hereinafter simply referred to as “wafer”) is provided. The wafer W is an example of a substrate that is a plasma processing target.

  An electrostatic chuck 106 for electrostatically attracting the wafer W is provided on the upper surface of the mounting table 20. The electrostatic chuck 106 has a structure in which a chuck electrode 106a is sandwiched between insulators 106b. A DC voltage source 112 is connected to the chuck electrode 106a, and a current is supplied from the DC voltage source 112 to the electrode 106a, whereby the wafer W is attracted to the electrostatic chuck 106 by a Coulomb force.

  The mounting table 20 is supported by the support body 104. A coolant channel 104 a is formed inside the support body 104. A refrigerant inlet pipe 104b and a refrigerant outlet pipe 104c are connected to the refrigerant flow path 104a. For example, cooling water or the like is circulated as appropriate in the refrigerant flow path 104a.

  The heat transfer gas supply source 85 supplies a heat transfer gas such as helium gas (He) or argon gas (Ar) to the back surface of the wafer W on the electrostatic chuck 106 through the gas supply line 130. With this configuration, the temperature of the electrostatic chuck 106 is controlled by the cooling water circulating through the refrigerant flow path 104a and the heat transfer gas supplied to the back surface of the wafer W. As a result, the wafer can be controlled to a predetermined temperature.

  A power supply device 30 that supplies two-frequency superimposed power is connected to the mounting table 20. The power supply device 30 includes a first high-frequency power source 32 that supplies a first high-frequency power (plasma generation high-frequency power) having a first frequency, and a second high-frequency power (for generating a bias voltage) that is lower than the first frequency. A second high-frequency power source 34 for supplying high-frequency power). The first high frequency power supply 32 supplies, for example, a first high frequency power of 40 MHz, and the second high frequency power supply 34 supplies, for example, a second high frequency power of 3.2 MHz.

  The first high frequency power supply 32 is electrically connected to the mounting table 20 via the first matching unit 33. The second high frequency power supply 34 is electrically connected to the mounting table 20 via the second matching unit 35. The first and second matching units 33 and 35 match the load impedance to the internal (or output) impedance of the first and second high-frequency power sources 32 and 34, respectively. The first and second matching units 33 and 35 function so that the internal impedance and the load impedance of the first and second high-frequency power sources 32 and 34 seem to coincide with each other when plasma is generated in the chamber 10. .

  The gas shower head 25 is attached to the ceiling portion of the chamber 10 through an insulating shield ring 40 that covers the peripheral edge portion of the gas shower head 25. The gas shower head 25 may be electrically grounded or connected to a variable direct current power source (not shown) so that a predetermined direct current (DC) voltage is applied to the gas shower head 25.

  The gas shower head 25 is formed with a gas inlet 45 for introducing gas from the gas supply source 15. Inside the gas shower head 25, there are provided a center side diffusion chamber 50a and an edge side diffusion chamber 50b for diffusing the gas introduced from the gas introduction port 45.

  The gas shower head 25 is formed with a number of gas supply holes 55 for supplying gas from the diffusion chambers 50 into the chamber 10. Each gas supply hole 55 is arranged so that gas can be supplied between the mounting table 20 and the gas shower head 25.

  With this configuration, the first gas is supplied from the outer edge portion of the gas shower head 25, and the second gas having a gas type or gas ratio different from that of the first gas is supplied from the central portion of the gas shower head 25. Can be controlled. As a result, when forming a desired pattern on the electrostatic chuck 106, the thickness and quality of the film formed on the outer edge portion of the electrostatic chuck 106 and the film formed on the central portion can be controlled differently. It is.

  The exhaust device 65 is connected to an exhaust port 60 provided on the bottom surface of the chamber 10. The exhaust device 65 exhausts the gas in the chamber 10, thereby maintaining the interior of the chamber 10 at a predetermined degree of vacuum.

  A gate valve G is provided on the side wall of the chamber 10. The wafer W is carried into the chamber 10 from the gate valve G, and is carried out of the chamber 10 from the gate valve G after the plasma processing.

  The plasma processing apparatus 1 is provided with a control unit 100 that controls the operation of the entire apparatus. The control unit 100 includes a CPU (Central Processing Unit) 105, a ROM (Read Only Memory) 110, and a RAM (Random Access Memory) 115. The CPU 105 executes plasma processing, which will be described later, according to various recipes stored in a storage area such as the RAM 115. The recipe includes process time, pressure (gas exhaust), high frequency power and voltage, various process gas flow rates, chamber temperature (upper electrode temperature, chamber side wall temperature, ESC temperature, etc.) that are control information of the apparatus for each process. Etc. are described. In addition, the recipe which shows these programs and process conditions may be memorize | stored in the hard disk and semiconductor memory which are not shown in figure. Further, the recipe may be stored at a predetermined position in the storage area in a state of being stored in a portable computer-readable storage medium such as a CD-ROM or DVD.

  The overall configuration of the plasma processing apparatus 1 according to this embodiment has been described above. With the plasma processing apparatus 1 having such a configuration, plasma processing is executed in the order of (1) film formation processing for pattern formation of the electrostatic chuck 106 → (2) etching processing of the wafer W → (3) waferless dry cleaning processing. The

  (1) In a film forming process for forming a pattern of the electrostatic chuck 106, a stencil mask on which a desired pattern is formed is carried into the chamber 10 and placed on the electrostatic chuck 106 on which no pattern is formed. . Next, a film forming gas is supplied from the gas supply source 15 into the chamber 10. Plasma is generated from the deposition gas by the high frequency power supplied into the chamber 10 from the first and second high frequency power sources 32 and 34. A desired pattern is formed on the surface of the electrostatic chuck 106 by the generated plasma. After processing, the stencil mask is unloaded from the chamber 10.

  (2) In the etching process of the wafer W, the wafer W is carried into the chamber 10 and placed on the mounting table 20. Next, an etching process gas and high-frequency power are supplied into the chamber 10 to generate plasma. Plasma etching is performed on the wafer W by the generated plasma. After the processing, the wafer W is unloaded from the chamber 10.

  (3) In the waferless dry cleaning process, a cleaning gas and high frequency power are supplied into the chamber 10 without the wafer W being placed on the electrostatic chuck 106, and plasma is generated. The inside of the chamber 10 is cleaned by the generated plasma. The cleaning process may be performed with the wafer W placed on the electrostatic chuck 106.

  Hereinafter, a configuration of a stencil mask used for pattern formation of the electrostatic chuck 106 according to the present embodiment and a plasma processing method (film formation processing for pattern formation) using the stencil mask will be described.

[Structure of stencil mask]
The configuration of the stencil mask according to this embodiment will be described with reference to FIG. The stencil mask according to this embodiment functions as a mask for forming a pattern on the electrostatic chuck 106. The surface of the electrostatic chuck 106 on which the stencil mask is placed may be flat and have no pattern at all, or the simplest pattern may be formed.

  As shown in FIG. 2, the stencil mask 26 according to the present embodiment includes a disk-shaped first mask 21 having a desired pattern formed at the center and a ring-shaped second mask 22 on the outer periphery thereof. Have. The second mask 22 is arranged on the outer periphery of the first mask 21 with a predetermined gap from the first mask 21.

  The first mask 21 and the second mask 22 are separate, and have a predetermined width so as to form a ring-shaped film (hereinafter also referred to as “seal band”) on the outer peripheral side of the electrostatic chuck 106. The gap is provided. In the seal band, heat transfer gas introduced between the wafer W and the electrostatic chuck 106 to promote heat dissipation of the wafer W during plasma processing is generated between the wafer W and the electrostatic chuck 106. Suppresses leakage to the outer peripheral side.

  In addition, a lattice-like pattern is formed on the first mask 21. As a result, a lattice-like surface pattern is formed on the surface of the electrostatic chuck 106 inside the seal band. As described above, in this embodiment, an optimum surface pattern corresponding to the target process can be formed on the electrostatic chuck 106.

  When the first mask 21 and the second mask 22 are separated and cannot be transported as a single unit, the first mask 21 and the second mask 22 are transported after film formation by transporting one of the masks. Then, the mask is unloaded and the other mask is loaded to form a film.

  In this case, since the transfer process and the plasma process are performed twice, the inside of the chamber 10 must be released to the atmosphere after completing the formation of the surface pattern after carrying one mask into the chamber 10. As a result, the transfer time, the adjustment time of the atmosphere in the chamber 10, the film formation time, etc. take twice or more time to complete the formation of the surface pattern, and the efficiency is remarkably reduced. To do. In addition, a plurality of holding pins (not shown) provided in the plasma processing apparatus 1 hold the wafer W mainly on the back surface of the wafer W in the central portion of the electrostatic chuck 106, so that the second mask having an open central portion is provided. It is difficult to hold 22 with a plurality of holding pins.

  Therefore, as shown in FIGS. 2A and 2B, the stencil mask 26 according to the present embodiment includes four bridge members 23 that connect the first mask 21 and the second mask 22. . Each bridge member 23 has one end connected to the first mask 21, the other end connected to the second mask 22, and the first at a position higher than the top surfaces of the first mask 21 and the second mask 22. The mask 21 and the second mask 22 are bridged. As shown in FIG.2 (b), in this embodiment, the four bridge members 23 are arrange | positioned equally facing, and bridge | bridging the 1st mask 21 and the 2nd mask 22 from 4 directions, A stencil mask 26 in which the first mask 21 and the second mask 22 are integrated is created.

  However, the number of the bridge members 23 may be three or more, and the bridge member 23 may connect the first mask 21 and the second mask 22 at three or more locations. Further, the bridge members 23 do not necessarily need to be arranged uniformly, and are arranged so that the connection state between the first mask 21 and the second mask 22 is maintained when the stencil mask 26 is conveyed. That's fine. With this configuration, the first mask 21 and the second mask 22 are bridged at three or more locations by three or more bridge members 23. With this configuration, the stencil mask 26 that can carry the first mask 21 and the second mask 22 at a time is formed.

  The inner diameter R1 of the second mask 22 is smaller than the diameter R0 of the mounting table 20 below the electrostatic chuck 106 on which the stencil mask 26 is mounted. Further, the outer diameter R <b> 2 of the second mask 22 is larger than the diameter R <b> 0 of the mounting table 20 below the electrostatic chuck 106. Thereby, the space S is formed into a ring shape, and a seal band is formed on the outer peripheral portion of the electrostatic chuck 106.

  The height h of the bridge member 23 may be a height that allows the bridge member 23 to wrap around the space S below the bridge member 23 when the film forming gas becomes plasma and diffuses in the chamber 10. Therefore, the 1st mask 21 and the 2nd mask 22 need to be bridged in the position higher than the surface. Thereby, the plasma generated from the film forming gas flows under the bridge member 23, and the seal band can be formed in the space S below the bridge member 23. The bridge member 23 is not limited to a U-shape, and may have any shape such as an arcade shape or a triangle shape so long as the film forming gas can enter the space S below the bridge member 23.

  As the material of the first mask 21 and the second mask 22, silicon (Si), quartz, heat-resistant resin, or the like can be used. Since the first mask 21 and the second mask 22 are used for film formation using plasma, a plastic having poor heat resistance is not suitable for the material.

  The first mask 21 is one of a plurality of masks having different patterns depending on the type of plasma processing performed on the wafer W. The pattern of the first mask 21 may be, for example, a lattice pattern, a dot pattern, a circle pattern in which a plurality of concentric circles are formed, or any other pattern. By forming a film using plasma, a surface pattern having a width of about several μm or more can be formed on the electrostatic chuck 106.

  The surface pattern has an important function of determining the temperature of the wafer W. Therefore, the surface pattern of the electrostatic chuck 106 varies depending on the model, and in this embodiment, the surface pattern is optimized according to the target process.

  As shown in FIG. 4, the shape of the side surface of the pattern when forming the pattern of the stencil mask 26 may be vertical (straight edge). However, when a material having a high affinity for the film formation D is used, unnecessary protrusions may be formed on the edge of the film formation D as shown in FIG. In this case, when the stencil mask 26 is detached from the electrostatic chuck 106 after film formation, the surface pattern formed on the electrostatic chuck 106 may be damaged.

  Therefore, as shown in FIG. 4B, the side surface of the desired pattern formed on the stencil mask 26 may be formed in a tapered shape. Moreover, as shown in FIG.4 (c), the front-end | tip part of the side surface of the desired pattern formed in the stencil mask 26 may be formed in a taper shape (trumpet shape). FIG. 4C shows an example of the stencil mask 26 in which the tip of the side surface of the pattern is formed in a tapered shape. Thereby, it is possible to avoid the formation of unnecessary protrusions on the edge of the film formation D by providing the film formation with anisotropy. This can prevent the surface pattern formed on the electrostatic chuck 106 from being damaged when the stencil mask 26 is detached from the electrostatic chuck 106. The example of FIG. 4 is an example, and the shape of the side surface of the pattern of the stencil mask 26 is not limited to this.

  In the film forming step, the first gas is supplied to the outer peripheral portion of the mounting table 20 from the diffusion chamber 50b (see FIG. 1) located above the second mask 22. Further, a second gas having a gas type or a gas ratio different from that of the first gas is supplied from the diffusion chamber 50 a located above the first mask 21 to the central portion of the mounting table 20. Thereby, when forming a desired pattern on the electrostatic chuck 106, the thickness and film quality of the pattern formed on the central portion of the electrostatic chuck 106 and the seal band formed on the outer edge portion are controlled to be different. it can. However, the first gas and the second gas may have the same gas type and gas ratio.

[Plasma treatment method]
Next, the plasma processing method according to the present embodiment will be described with reference to FIGS. FIG. 5 is a flowchart showing an example of the plasma processing method according to the present embodiment. FIG. 6 is a diagram conceptually showing the plasma processing method of FIG. The plasma processing method according to the present embodiment includes a process of forming a surface pattern of the electrostatic chuck 106 using the stencil mask 26.

  First, an electrostatic chuck 106 without a pattern is prepared in the chamber 10 (step S1, FIG. 6A), and the stencil mask 26 is transported and installed on the electrostatic chuck 106 (step S2, FIG. b)). The installed first mask 21 and second mask 22 may be electrostatically attracted by the electrostatic chuck 106.

  In this state, a film formation process is performed in the plasma processing apparatus 1 under predetermined process conditions described later, and a surface pattern is formed on the electrostatic chuck 106 (step S3, FIG. 6C). . Here, a surface pattern of several microns can be formed by using plasma.

  Next, the stencil mask 26 is removed from the plasma processing apparatus 1 (step S4, FIG. 6D). Next, a wafer W to be a product is carried into the plasma processing apparatus 1, and plasma processing such as etching, film formation, and ashing is performed using the plasma processing apparatus 1, and the product processing of the wafer W is completed (step) S5).

  In the product processing of the wafer W, when the type of the product of the wafer W to be processed next is different from the type of the product processed immediately before, the pattern on the electrostatic chuck 106 is removed and it is optimum for the product to be processed next. It is preferable to form a patterned pattern (in the case of maintenance). In addition, even if the product type is the same, if the surface pattern collapses over time, it is preferable to repair the pattern on the electrostatic chuck 106 (in the case of repair).

  Therefore, it is determined whether or not maintenance or repair is required for each wafer after a predetermined time has elapsed, after product processing of a predetermined number of wafers W has been executed, or for each wafer (step S6).

  If it is determined in step S6 that maintenance is necessary, the pattern on the electrostatic chuck 106 is removed by plasma (step S7). Thereafter, the stencil mask 26 is placed on the electrostatic chuck 106 from which the pattern of step S1 has been removed (steps S1 and S2), and a surface pattern is formed again on the electrostatic chuck 106 (step S9). Thereby, the surface pattern optimized according to the next product process (step S11) can be formed on the electrostatic chuck 106.

  Next, the mask is removed (step S10), plasma processing is performed on the wafer W, and product processing of the wafer W is completed (step S11). After a predetermined time has elapsed, after a predetermined number of lots of product processing have been executed, or whether maintenance or repair is required for each wafer is determined (step S6), processing according to the determination result is repeated.

  On the other hand, if the repair is determined in step S6, the stencil mask 26 is placed on the electrostatic chuck 106 (step S2), and a surface pattern is formed on the electrostatic chuck 106 again. Thereby, the surface pattern which collapsed with time can be repaired. The positioning of the stencil mask 26 may be performed by matching the mark formed on the stencil mask 26 with the mark formed on the electrostatic chuck 106.

The cleaning process shown in FIG. 6E may be performed after the pattern formation in steps S3 and S9 and the mask removal in steps S4 and S10 and before the product process in steps S5 and S11. In that case, for example, cleaning with O ₂ plasma may be performed in a state where the dummy wafer DW is placed on the electrostatic chuck 106. Thereby, the film adhering to the inner wall of the chamber 10 can be removed during the formation of the surface pattern (steps S3 and S9), and the generation of particles during product processing can be suppressed.

[Plasma treatment: Example of process conditions during surface pattern formation]
Finally, an example of process conditions in the surface pattern film forming process will be briefly described. The process conditions in the surface pattern film forming process are SiO ₂ type, Si type, CF type, C type, SiC film depending on the type of target process, the target process or the purpose of the plasma processing. .

As the gas species, in the case of an SiO ₂ based film, a mixed gas of SiCl ₄ gas and O ₂ gas or a mixed gas of SiF ₄ gas and O ₂ gas can be used.

In the case of a Si-based film, a mixed gas of SiCl gas and H ₂ gas or a mixed gas of SiF ₄ gas and H ₂ gas can be used.

In the case of a CF-based film, CF ₄ gas, C ₄ F ₈ gas, and C ₄ F ₆ gas can be used.

For C-based film, SiC film, CH ₄ and gas mixture and gas of SiCl ₄ gas and CH ₄ gas, it is possible to use a mixed gas of SiF ₄ gas and CH ₄ gas.

[Plasma treatment: Process condition example during cleaning]
In this embodiment, it is preferable to perform the cleaning process during the product process. In this case, it is assumed that waferless dry cleaning is employed. Therefore, the process conditions in the waferless dry cleaning are set such that the surface pattern on the electrostatic chuck 106 is not damaged.

For example, in the case of the plasma processing apparatus 1 that etches an oxide film (O _x film), it is preferable to use a gas that does not contain fluorine, such as O ₂ , as the cleaning gas. At that time, it is necessary to form a film on the electrostatic chuck 106 that is not scraped by the plasma generated from the O ₂ gas in the waferless dry cleaning. In the case of etching an oxide film, the surface pattern is preferably a silicon-containing film such as a SiO ₂ film or a Si film. When the surface pattern of the electrostatic chuck 106 is a silicon-containing film, it is preferable to use plasma using SF ₆ gas or NF ₃ gas in order to remove the surface pattern.

For example, in the case of the plasma processing apparatus 1 that etches a polysilicon film (Poly-Si film), it is preferable to use plasma generated from a fluorine-based gas as the cleaning gas. At that time, it is necessary to form a film on the electrostatic chuck 106 that is not scraped by the plasma generated from the CF base gas in the waferless dry cleaning. In the case of etching a polysilicon film, the surface pattern is preferably a carbon (C) -containing film. When the surface pattern of the electrostatic chuck 106 is a carbon-containing film, it is preferable to use plasma using O ₂ gas or H ₂ gas in order to remove the surface pattern.

  The stencil mask according to the present embodiment and the plasma processing method including the formation of the surface pattern of the electrostatic chuck 106 using the stencil mask have been described above. According to this, the surface pattern of the electrostatic chuck 106 can be optimized by the target process without replacing the electrostatic chuck 106. In the present embodiment, the first mask 21 and the second mask 22 are transported at a time using the stencil mask 26 in which the first mask 21 and the second mask 22 are integrated by the bridge member 23. Can do. Thereby, after placing the stencil mask 26 on the placing table 20, a desired pattern can be formed on the electrostatic chuck 106 without releasing the chamber 10 to the atmosphere. As a result, the surface pattern formed on the electrostatic chuck 106 can be easily formed, the number of steps for manufacturing an actual part can be greatly reduced, and good plasma processing can be performed on the wafer W at low cost.

  In the product processing of the wafer W to be plasma-processed, when the type of the product to be processed next is different from the type of the product processed immediately before, the pattern is removed and the optimum pattern for the type of product to be processed next Can be formed on the electrostatic chuck 106. Furthermore, even if the type of product is the same, if the surface pattern collapses over time, the surface pattern can be repaired without removing the pattern (in the case of repair). From the above, even when the number of wafers of the same type is small or when various types of wafers are processed, the surface pattern optimized for each product type can be electrostatically replaced without replacing the electrostatic chuck 106. A film can be formed on the chuck 106. Thereby, the temperature adjustment of the wafer W can be controlled efficiently at low cost, and the in-plane uniformity of the temperature of the wafer W can be enhanced.

  In addition, for example, the surface formed on the electrostatic chuck 106 such as the insulating film and the semiconductor film are separately formed at the center (inner periphery) and the outer edge (outer periphery) of the electrostatic chuck 106. In the pattern, the thickness and film quality of the inner peripheral film and the outer peripheral film of the electrostatic chuck 106 can be made different. As a result, it is possible to prevent partial adsorption of the wafer W from being adsorbed and to prevent adsorption failure due to residual charges on the wafer W.

  As described above, the stencil mask, the plasma processing apparatus, and the plasma processing method have been described in the above embodiment. However, the stencil mask, the plasma processing apparatus, and the plasma processing method according to the present invention are not limited to the above embodiment, and various modifications and improvements can be made within the scope of the present invention. The matters described in the above embodiments can be combined within a consistent range.

  For example, the plasma processing apparatus for performing plasma processing including pattern formation according to the present invention is applicable not only to the capacitively coupled plasma (CCP) apparatus shown in FIG. 1 but also to other plasma processing apparatuses. . Other plasma processing apparatuses include inductively coupled plasma (ICP), a CVD (Chemical Vapor Deposition) apparatus using a radial line slot antenna, a Helicon Wave Plasma (HWP) apparatus, an electronic It may be a cyclotron resonance plasma (ECR) apparatus or the like.

  The substrate processed by the plasma processing apparatus according to the present invention is not limited to a wafer, and may be, for example, a large substrate for a flat panel display, a substrate for an EL element, or a solar cell.

  Note that the coating technique for protecting the surface of the electrostatic chuck 106 from damage during waferless dry cleaning is not within the scope of the present invention. In the present invention, there is an area that is not partially protected on the surface of the electrostatic chuck 106 in order to form an optimum pattern on the electrostatic chuck. For example, in the case of a dot pattern, a portion corresponding to a dot is coated, but a portion without a dot is not coated.

1: Plasma processing apparatus 10: Chamber 15: Gas supply source 20: Mounting table (lower electrode)
21: First mask 22: Second mask 23: Bridge member 25: Gas shower head (upper electrode)
26: Stencil mask 30: Power supply device 85: Heat transfer gas supply source 100: Control unit 106: Electrostatic chuck

Claims (11)

A first mask on which a desired pattern is formed;
A second mask arranged at a predetermined gap from the first mask at an outer periphery of the first mask;
One end is connected to the first mask, the other end is connected to the second mask, and the bridge member bridges the first and second masks at a position higher than the first and second masks. And having
The stencil mask, wherein the first and second masks are bridged and integrated at three or more locations by three or more bridge members. The inner diameter of the second mask is smaller than the diameter of the mounting table under the electrostatic chuck on which the stencil mask is disposed,
The outer diameter of the second mask is larger than the diameter of the mounting table.
The stencil mask according to claim 1. The stencil mask is formed such that at least the tip of the side surface of the desired pattern is tapered.
The stencil mask according to claim 1 or 2. The first mask is one of a plurality of masks having different patterns depending on the type of plasma processing performed on the substrate.
The stencil mask as described in any one of Claims 1-3. A chamber having an electrostatic chuck;
A gas supply source for supplying gas into the chamber;
A high frequency power source for applying high frequency power in the chamber,
The stencil mask according to any one of claims 1 to 4 is disposed on an electrostatic chuck,
A plasma is generated from the supplied gas by the applied high frequency power, and a film having a desired pattern is formed on the electrostatic chuck by the generated plasma.
Plasma processing equipment. A gas shower head for introducing the gas into the chamber;
Supplying a first gas from the gas shower head to the outer edge of the chamber, and supplying a second gas having a gas type or gas ratio different from the first gas to the central portion of the chamber;
Adjusting the film thickness or film quality between the outer edge and the center of the pattern formed on the electrostatic chuck by the generated plasma;
The plasma processing apparatus according to claim 5. A plasma processing method for performing plasma processing on a substrate on an electrostatic chuck in a chamber,
The stencil mask according to any one of claims 1 to 4 is disposed on an electrostatic chuck,
Supplying gas into the chamber;
Applying high frequency power in the chamber;
A plasma is generated from the supplied gas by the applied high frequency power, and a film having a desired pattern is formed on the electrostatic chuck by the generated plasma.
A plasma processing method including processing. Unloading the stencil mask from the chamber;
After the plasma processing of one or several lots of substrates is performed or after a predetermined time has elapsed, the stencil mask is carried into the chamber and placed on the electrostatic chuck,
A film having a new pattern is formed on the electrostatic chuck by plasma.
The plasma processing method of Claim 7 including a process. The process of placing the stencil mask on the electrostatic chuck includes:
Performed after removing a desired pattern on the electrostatic chuck;
The plasma processing method according to claim 8. In the process of forming the desired pattern film,
Plasma is diffused into the space between the first and second masks under the bridge member of the stencil mask;
The plasma processing method as described in any one of Claims 7-9. A first gas is supplied from an outer edge portion of a gas shower head for introducing the gas into the chamber, and a second gas having a gas type or a gas ratio different from that of the first gas is supplied from a central portion of the gas shower head. Supply
The generated plasma adjusts the thickness of the film at the outer edge and the film at the center of the pattern formed on the electrostatic chuck.
The plasma processing method as described in any one of Claims 7-10.

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