JP4140763B2 - Plasma processing apparatus and plasma processing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a plasma processing apparatus.And plasma processing methodIn particular, a plasma processing apparatus for sputter deposition, dry etching, or chemical vapor deposition with a wafer heating mechanism to reduce particles on the backside of the wafer before the wafer undergoes plasma-assisted wafer processingAnd plasma processing methodAbout.
[0002]
[Prior art]
Semiconductor wafer processing with or without plasma is an essential step in the manufacture of integrated circuits. It is important to maintain the desired temperature or temperature range in order to obtain the desired results during wafer processing. For example, a high-temperature substrate is required for some of sputter deposition and chemical vapor deposition. Currently, the temperature of the wafer is typically increased by placing the wafer on a heating plate that is used as an electrode. If the wafer is simply placed on the heated electrode, there is not enough thermal conductivity between the wafer and the heated electrode. Therefore, the wafer must be electrostatically clamped (fixed) on the heating electrode. The electrostatic clamping mechanism provides better thermal conductivity between the wafer and the heating electrode. Thus, the wafer temperature is usually maintained at a desired level.
[0003]
Here, Patent Document 1 can be cited as a prior art.
[0004]
[Patent Document 1]
US Pat. No. 5,530,616
[0005]
[Problems to be solved by the invention]
However, the above techniques have several problems, such as the difficulty of forming and releasing the clamp on the backside of the wafer. These problems are described in detail with reference to FIGS.
[0006]
FIG. 5 shows a cross-sectional view of a plasma processing apparatus provided with a conventional electrostatic chuck (ESC). FIG. 6 is an enlarged view of a portion denoted by “A” in FIG. For ease of explanation, a configuration of a sputter deposition plasma processing apparatus is conceivable. The plasma processing apparatus includes rf electrodes 64 and 65, a wafer holder 101, a side wall 61, a bottom plate 62, a gas intake port 63, a top plate 66, and a gas exhaust port 69. The rf power generated by the rf power source 68 is supplied to the rf electrodes 64 and 65 through the matching circuit 67. The rf electrodes 64 and 65 make the upper electrode device 102. The upper electrode device 102 is supported by a dielectric material 71. Plasma is generated in the plasma processing region by a capacitively coupled mechanism. The generation of plasma causes the generation of a negative self-bias voltage on the rf electrodes 64 and 65.
[0007]
Due to this negative self-bias voltage, the lower rf electrode 64 is sputtered by impact ions. The lower rf electrode 64 needs to be sputtered and is made of a material that is deposited on the surface of the substrate. The lower rf electrode 64 is a target. Some of these sputtered atoms are deposited on the surface of the wafer 57. If the negative voltage of the self-bias is not sufficient to obtain an appropriate film formation rate, a higher negative voltage can be applied from the rf power source 68 to the rf electrodes 64 and 65. The circuit for supplying the voltage is not shown in the figure.
[0008]
Since the problems with the conventional wafer heating method using the electrostatic chuck (ESC) 80 are important with respect to the present invention, the configuration and operation of the ESC 80 will be described in detail.
[0009]
The ESC 80 includes a dielectric layer 51 and a metal electrode 52. The ESC 80 is a part for incorporating the wafer holder 101. In addition to the ESC 80, the wafer holder 101 also includes an insulating material 53, sidewalls 54, and wafer lift pins 56. The wafer holder 101 is disposed on the bottom plate 62. The metal electrode 52 is a lower electrode that is electrically insulated from the rest of the hardware by being placed in the insulating material 53. The thickness of the metal electrode 52 is not an important matter and is usually in the range of 1 mm to several cm. The metal electrode 52 has a heating mechanism 72.
[0010]
The metal electrode 52 can be connected to either the DC voltage supply 55 or ground via the two-way switch 103. The metal electrode 52 is supplied with an rf current from an rf generator. The circuit for providing the rf current is not shown in the figure. However, the supply of rf current to the metal electrode 52 is not essential for the expected purpose, ie the wafer clamping process. If rf current is applied to the metal electrode 52, the frequency of the rf current is in the range of 100 kHz to 50 MHz, typically lower than 2 MHz.
[0011]
Usually, the material of the dielectric layer 51 is Al.₂O_ThreeAlN, polyimide, or the like is used. The thickness and resistance of the dielectric layer 51 have a great influence on the efficiency of clamping and unclamping (chucking) of the wafer. However, the thickness of the dielectric layer 51 is not important and is usually in a range smaller than 5 mm. A plurality of embossings 58 are formed on the upper surface of the dielectric layer 51, so that when the wafer 57 is placed on the ESC 80, the back surface of the wafer 57 contacts only the embossments 58. The height of the emboss 58 is in the range of 5 to 25 μm. Because of these embossings 58, there is a space 59 between the wafer 57 and the dielectric layer 51, which is usually filled with an inert gas for better heat transfer between the wafer 57 and the ESC 80. .
[0012]
During operation, the metal electrode 52 is connected to a DC voltage supply 55 and is provided with an appropriate DC voltage. At that time, charges accumulate on the metal electrode 52. Since there is a dielectric layer 51 between the metal electrode 52 and the Si (silicon) wafer 57, an opposite charge is induced on the back surface of the wafer 57. Charges of opposite polarity on wafer 57 and ESC 80 form an electrostatic force that clamps wafer 57 on ESC 80.
[0013]
Normally, when the wafer 57 is loaded onto the wafer holder 101, particularly when it arrives on the electrostatic chuck 80, the temperature of the wafer is at room temperature. If sputter (or any other process) must be performed at a higher temperature, eg, 300 ° C., first the wafer 57 is over the heated ESC 80 to heat the wafer 57, Electrostatically clamped. During the heat treatment, the wafer 57 undergoes thermal expansion. However, since the wafer 57 is electrostatically clamped on the ESC 80, higher friction will occur between the back surface of the wafer and the top surface of the emboss. This results in rubbing with the backside of the wafer and / or the embossing material that produces particles 70.
[0014]
Some of these particles adhere directly to the backside of the wafer. The remaining portion is deposited on the upper surface of the ESC 80. Some of these deposited particles then adhere to the backside of the next wafer. However, at the same time, a large amount of new particles 70 are generated. Thus, during the heat treatment of each wafer, particles 70 are generated and some of these particles 70 adhere to the backside of the wafer.
[0015]
When the metal electrode 52 is supplied with a DC voltage from the DC voltage supply 55, charges are accumulated on the metal electrode 52. However, these charges are caused by a strong electric field E between the wafer 57 and the metal electrode 52.₁Therefore, it slowly moves to the upper surface of the dielectric layer 51. This is shown schematically in FIG. The transfer of charge to the top surface of the dielectric layer 51 is likewise supported by the fact that the dielectric layer 51 is usually not a perfect insulator. Further, the material of the dielectric material 51 may be intentionally doped with impurities in order to reduce electrical resistance. This enhances the charge transfer to the upper surface of the dielectric layer 51.
[0016]
On a fine microscopic scale, the lower surface of the Si wafer 57 and the upper surface of the emboss 56 have a rough surface. Therefore, the actual contact points between the wafer 57 and the dielectric layer 51 are made only in a few places, as shown in FIG. The spacing between the wafer 57 and the dielectric layer 51 is limited by the thickness of the vacuum or air pocket 73 between them. That is, the distance between charges having opposite polarities is extremely small. This leads to a very strong attractive electrostatic force between the wafer 57 and the ESC 80.
[0017]
After the processing of the wafer is completed, the voltage applied to the metal electrode 52 is disconnected and the metal electrode 52 is connected to ground. This is for the purpose of neutralizing the charge accumulated on the metal electrode 52, thereby eliminating the effect of electrostatic forces on the wafer surface. However, at this point, some of the charge is on the top surface of the dielectric layer 51. Therefore, even if the metal electrode 52 is electrically grounded, the electrostatic force acting on the surface of the wafer is neutralized until all charges accumulated on the top surface of the dielectric layer 51 are neutralized. It will not be zero. This process is time consuming because there is an electrical resistance to charge transfer in the dielectric layer 51. Therefore, immediate unclamping is not possible.
[0018]
  An object of the present invention is to provide a plasma processing apparatus equipped with a wafer heating mechanism that can eliminate generation of particles and adhesion to the back surface of a wafer and can perform immediate clamping release.And plasma processing methodIs to provide.
[0019]
[Means for Solving the Problems]
  Plasma processing apparatus according to the present inventionAnd plasma processing methodIn order to achieve the above object, is configured as follows.
[0020]
  The first plasma processing apparatus comprises a wafer heating process that operates before the wafer is subjected to plasma assisted processing,Further, a flat plate, a wafer holder having a plurality of wafer lift pins for lifting the wafer during the wafer heating process, and a wafer that is in a positional relationship parallel to the wafer and that is rotated by a rotating rod and lifted by the wafer lift pins A moving shutter that covers the entire surface of the shutter, and a shutter housing portion for housing the moving shutter. The moving shutter includes a heating mechanism and a metal flat plate heated by the heating mechanism below the heating mechanism. The wafer is heated by radiation of heat from the heated flat bottom plate.
[0021]
In the above plasma processing apparatus, the moving shutter provided with the heating mechanism is rotated by, for example, 180 ° around its axis, or linearly protrudes from the shutter housing portion, so that a few micrometers above the wafer or It can be located several millimeters above and parallel to the wafer.
[0022]
In the plasma processing apparatus, the moving shutter has a temperature sensor and a temperature control mechanism that controls the heating mechanism based on a detection signal of the temperature sensor.
[0023]
In the plasma processing apparatus, the moving shutter maintains a predetermined temperature, and when the moving shutter is at an upper position of the wafer, for example, by radiation, conduction, or convection, the heat is transmitted to the wafer at a desired temperature. Heat.
[0024]
In the plasma processing apparatus, the moving shutter heats the wafer to a predetermined temperature before the plasma is ignited, and then the moving shutter moves to the shutter accommodating portion, the plasma is ignited and maintained, and the wafer processing is executed. The
[0025]
In the plasma processing apparatus, the wafer is placed over the pins during wafer heating and during wafer processing, and these pins protrude a few micrometers or a few millimeters above the flat plate of the wafer holder. .
[0026]
In the plasma processing apparatus, the wafer is placed on pins during wafer processing, these pins projecting a few micrometers or a few millimeters above the flat plate of the wafer holder, and the wafer is a plasma assisted wafer. Placed on a flat plate during processing.
[0027]
In the plasma processing apparatus, the flat plate of the wafer holder is heated or cooled to a desired temperature by using an appropriate heating or cooling mechanism.
[0028]
  A wafer heating mechanism, particularly a shutter, in the plasma processing reaction vessel is used to cover or open the wafer and consists of a heating mechanism that heats the wafer before it undergoes plasma assisted wafer processing. During the heat treatment and plasma treatment, the wafer is placed on three or several pins protruding above a flat plate. The pins are used to contact the backside of the wafer at only three or several points and there is no electrostatic clamping, so particle generation and adhesion to the backside of the wafer is minimized and conventional unclamping The problem is solved.
  In the plasma processing method according to the present invention, before the plasma assisted processing, a moving shutter having a heating mechanism is disposed so as to cover the wafer,Place the wafer on the wafer lift pins only and at room temperatureThe waferUp to the temperature required for the second stepA first step of heating, and a second step of moving the moving shutter to the shutter housing portion and maintaining the plasma in an ignited state to perform wafer processing.
  In the plasma processing method described above, a third step of cooling the moving shutter is further provided after the second step.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments will be described with reference to the accompanying drawings. Details of the present invention will be made clear through the description of the embodiments.
[0030]
The first embodiment of the present invention will be described with reference to FIGS. For ease of explanation, a plasma processing apparatus used for sputtering film formation can be considered. FIG. 1 shows a longitudinal sectional view of a plasma processing apparatus provided with a heating mechanism according to the present invention. The plasma processing apparatus includes a plasma generation mechanism, a shutter 1, a wafer holder 2, a plurality of gas intake ports 3 and gas discharge ports 4, a cylindrical side wall 5, a top plate, and a bottom plate 7. FIG. 2 is a bottom view of the shutter 1. Wafer holder 2 is fixed to bottom plate 7. The shutter 1 is disposed above the wafer holder 2.
[0031]
The shutter 1 is movable. In FIG. 1, one method for moving the shutter is described. One end of the shutter 1 is fixed to the upper end of the rotating rod 8, which is provided in the vertical direction and is supported by the rotating rod 8. The rotating rod 8 is moved around its axis by using a motor 9, and the motor is fixed to the lower side of the bottom plate 7 of the plasma processing apparatus. Therefore, the shutter 1 is positioned so as to cover the entire surface of the wafer 10 by rotating the rotating rod 8, or is positioned in the shutter housing portion 11. When in the shutter storage 11, the position of the shutter 1 is indicated by an imaginary line in FIG. The mechanism described above for shutter movement is not the only way. Different techniques can be used to position the shutter 1 above the wafer 10 and within the shutter housing 11. For example, as the shutter 1 is positioned so as to cover the wafer 10, the shutter 1 can be moved along a horizontal straight line from the shutter accommodating portion 11.
[0032]
The wafer 10 mounted on the wafer holder 2 and the shutter 1 are in parallel positions. The vertical position of the shutter 1 is adjusted so that the distance between the wafer 10 and the lower surface of the shutter 1 is within a range of several micrometers to several millimeters. Usually, though not essential, the shutter 1 has a circular shape. If the shutter 1 has a circular shape, the diameter of the shutter 1 is larger than the diameter of the wafer 10. The thickness of the shutter 1 is not important, but can be changed in the range of 1 cm to 10 cm.
[0033]
Preferably, the main part of the shutter 1 is made of metal. A resistive heating wire 12, such as tungsten, is provided on the lower surface of the shutter 1 as shown in FIGS. However, as shown in FIG. 3, an IR (infrared ray) array or other techniques can be used as the heating source. Electrical wiring to the resistive heating wire 12 or IR lamp is provided through the rotating rod 8. An AC or DC power supply 33 supplies power to the heating wire 12 and the like through the electric wire. The heating wire 12 is electrically insulated from the rest of the hardware by utilizing a dielectric member. A plate that transmits infrared radiation, such as quartz, may cover the heating wire 12. Covering the heating wire 12 is useful for reducing particles falling from the heating wire 12 onto the surface of the wafer 10. The cover plate of the heating wire 12 is not shown in the figure.
[0034]
The wafer holder 2 is composed of a flat plate 14 and three or several pins 15 for lifting the wafer 10. The wafer lift pins 15 can move in the vertical direction. The vertical movement of the pin 15 is controlled by mechanical or electromechanical methods. In FIG. 1, the pin 15 is moved by motors 30, 31 or any other mechanical device. The diameter of the pin 15 is not critical and is typically about 1 mm. The material of the pin 15 is likewise not important. It is made of a dielectric or metal member. The flat plate 14 of the wafer holder 2 is also made by a metal or dielectric member 6 as well. Again, it may or may not have a heating or cooling mechanism. In this embodiment, the heating wire 20 that is powered by an AC or DC power supply 32 is included in the flat plate 14 as shown in FIG. Typically, the flat plate 14 is electrically isolated from the other components of the hardware by disposing a dielectric material 19.
[0035]
FIG. 1 shows a capacitively coupled plasma generation mechanism. The rf current generated from the rf power source 16 is applied to the upper electrodes 17 and 26 through the matching circuit 18. The frequency of the rf current is not critical and can vary from 1 MHz to 500 MHz. A DC voltage can be applied in addition to the rf current, and a negative voltage is normally applied to the upper electrodes 17 and 26. The circuit of the DC voltage supply is not shown in FIG. However, providing a DC voltage is not essential. The upper part 26 of the upper electrode comprises a cooling device 27 having a cooling medium inlet 23 and a cooling medium outlet 24. Further, even if a capacitively coupled rf plasma is shown in FIG. 1, different mechanisms for plasma generation, such as inductively coupled, wave heating, or DC plasma generation mechanisms can be used.
[0036]
There are a plurality of gas inlets 3 for supplying gas into the reaction vessel of the plasma processing apparatus, and a gas outlet 4 for evacuating the reaction vessel. The type of wafer processing determines the process gas or process gases. Ar gas is typically used in sputter deposition applications. Reference numeral 29 denotes a wafer loading / unloading door, and 34 denotes a vacuum exhaust port door.
[0037]
Next, the operation of the above-described plasma processing apparatus will be described. First, the wafer 10 is placed on the wafer holder 2. At this time, the shutter 1 is in the shutter housing 11. In order to place the wafer 10 on the wafer holder 2, the wafer 10 is first introduced into the plasma processing reaction vessel by a robot arm not shown in the figure. Then, three (or several) wafer lift pins 15 protrude above the flat plate 14 to receive the wafer 10. The pins 15 are gradually lowered until a narrow spacing between the wafer 10 and the flat plate 14 is created, typically approximately 1 mm. This spacing is not critical and can thus be made to be approximately 1 cm or larger. Thus, during wafer heating and wafer processing, the wafer 10 will be on the tip of the wafer lift pins 15.
[0038]
It is not essential to maintain a narrow spacing between the wafer 10 and the shutter 1. It is therefore possible to place the wafer 10 on the flat plate 14 of the wafer holder 2. Alternatively, the wafer 10 can be processed by heating the wafer 10 by placing it on the wafer lift pins 15 and placing it on the flat plate 14. However, it is appropriate to place the wafer 10 on the wafer lift pins 15 to minimize particle generation during the wafer heating process.
[0039]
Once the wafer 10 is in place, the shutter 1 is brought to cover the entire surface of the wafer by rotating the rotating rod 8. The heating wire 12 is actuated to heat the wafer 10. Heating the wafer basically occurs by radiation. However, the process of conduction and convection heating likewise contributes to heating the wafer depending on the pressure inside the reaction vessel. There is no special time for the operation of the heating wire 12. Thus, the heater 12 can be operated after the shutter 1 is brought onto the surface of the wafer, or the operating state of the heating wire can be continuously maintained. In the latter case, the shutter 1 is always maintained at a high temperature. The wafer 10 is heated for a predetermined time or until a predetermined temperature is reached, and then the shutter 1 is returned to the shutter housing portion 11. The plasma is then ignited with an appropriate gas or combination of gases to obtain the desired processing on the surface of the wafer. For example, capacitively coupled plasma is ignited, and the material of the upper electrode 17 is sputtered under an atmosphere of argon gas and deposited on the wafer surface.
[0040]
  When the shutter 1 is moved to the shutter accommodating portion 11, the wafer 10 starts to be cooled. However, at the same time the plasma was ignited,AdditionThe collision of heated gas and ions heats the wafer 10. In addition, infrared, visible and ultraviolet radiation generated in the plasma heats the wafer 10. These heating steps prevent or delay the wafer cooling step. The average temperature during wafer processing is at the initial temperature (after being heated by shutter 1), plasma parameters such as rf or DC power, pressure, gas temperature, and processing time, which is usually around 1 minute. Dependent.
[0041]
After the shutter 1 has been moved to the shutter housing 11, the temperature drop due to the cooling of the wafer 10 can be similarly prevented by placing the wafer 10 on a heated flat plate 14. In this case, the wafer 1 simply resides on a heated flat plate 14 and no electrostatic clamp is used. The flat plate 14 is heated by a resistive wire 20 embedded in the flat plate 14.
[0042]
Although the first embodiment has been described using a sputter deposition apparatus, it is possible to apply this technique to a chemical vapor deposition apparatus or a dry etching apparatus by appropriately modifying the described technique.
[0043]
In the technology according to the above-described invention, the wafer 10 is heated before the plasma is ignited. During this heating process, the wafer 10 is placed on several wafer lift pins 15. No electrostatic clamp is used. Therefore, thermal expansion of the wafer 10 during the heating process does not cause particle generation. Further, during plasma assisted wafer processing, the wafer 10 is placed only on the wafer lift pins 15. This minimizes the area of the contact surface between the wafer 10 and the wafer holder 2. This also contributes to reduced particle generation and reduced particle adhesion on the backside of the wafer. Furthermore, there is no electrostatic clamping during plasma assisted wafer processing, so there is no wafer unclamping step or need.
[0045]
Next, a second embodiment will be described with reference to FIG. This embodiment is an extension of the first embodiment. In the second embodiment, only the configuration of the shutter 1 is changed. Therefore, in FIG. 4, only a schematic view of the longitudinal section of the shutter 1 is shown. Except for the configuration of the shutter 1, all other hardware configurations and operation procedures of the plasma processing apparatus are the same as those described in the first embodiment.
[0046]
The shutter 1 causes the cooling medium to flow through the resistive heating wire 12, a flat bottom plate 42 made of a dielectric member or a metal member, a temperature sensor 43, and a cooling mechanism, particularly the main part 45 of the shutter 1. The groove 44 is provided with an inlet 35 and an outlet 36 for the cooling medium. However, the temperature sensor 43 and the cooling mechanism are not essential. The thickness of the flat bottom plate 42 is not critical and is usually about 10 mm. The diameter of the flat bottom plate 42 is likewise not critical and is simply larger than the diameter of the wafer. Preferably, the flat bottom plate 42 is made of metal.
[0047]
The heating wire 12 is connected to an AC or DC electric supply 33. The flat bottom plate 42 is heated to a predetermined temperature and is maintained at that temperature by using the heating wire 12 and the temperature sensor 43. Heating the flat bottom plate 42 to a predetermined temperature consumes considerable electrical energy. However, once the flat bottom plate 42 is heated to a predetermined temperature, only a smaller amount of power is required to maintain that temperature. Therefore, this configuration consumes less energy compared to that described in the first embodiment while the wafer processing is in execution mode.
[0048]
In this configuration of shutter 1, the heating wire does not heat the wafer directly. Instead, the heating wire 12 heats the bottom plate 42 made of a metal or dielectric material. The bottom plate 42 heats the wafer 10 mostly by a radiation process.
[0049]
There are other advantages to this configuration. Due to the constant temperature on the flat bottom plate 42, the temperature of its lower surface is very high and uniform. Therefore, the temperature of the wafer is likewise uniform over the entire surface. Another advantage is that the flat structure of the lower surface of the flat bottom plate 4 allows the distance between the wafer 10 and the shutter 1 to be maintained at a very small value, for example, less than 1 mm. This increases the heating efficiency and heating rate of the substrate.
[0050]
【The invention's effect】
The plasma processing apparatus of the present invention is heated to a desired temperature by using a thermal radiation process while the wafer is placed on several pins without using an electrostatic chuck. This method reduces the contact surface area of the wafer and wafer holder. This feature leads to particle minimization on the backside of the wafer. Furthermore, in the plasma processing apparatus of the present invention, since there is no electrostatic clamping of the wafer, the difficulty in releasing the clamp seen in the conventional plasma processing apparatus does not occur.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a plasma processing apparatus according to a first embodiment.
FIG. 2 is a bottom view of a shutter where a resistive wire is used to heat the wafer.
FIG. 3 is a bottom view of another configuration of a shutter in which an array of IR lamps is used to heat a substrate.
FIG. 4 is a longitudinal sectional view of a shutter used in the second embodiment.
FIG. 5 is a plasma processing apparatus in which a conventional electrostatic chuck is used for heating a wafer.
FIG. 6 is an enlarged view of a portion labeled “A” in FIG. 5;
[Explanation of reference signs]
1 Shutter
2 Wafer holder
8 Rotating rod
9 Motor
10 wafers
11 Shutter storage
12 Heating wire
14 Flat plate
15 Wafer lift pin
16 rf generator
17 Upper electrode
18 Matching circuit
20 Heating wire
38 IR lamp
42 Dielectric material
43 Temperature sensor

Claims (5)

Prior to the plasma assisted processing, a moving shutter having a heating mechanism is arranged to cover the wafer, and the wafer at room temperature is heated to the temperature required for the second step while the wafer is placed only on the wafer lift pins. A first step to:
A second step of moving the moving shutter to a shutter housing portion and maintaining the plasma in an ignition state to perform wafer processing;
A plasma processing method comprising:   The plasma processing method according to claim 1, further comprising a third step of cooling the movable shutter after the second step. A flat plate and a wafer holder having a plurality of wafer lift pins for lifting the wafer during wafer heat treatment ;
A moving shutter which covers the entire surface of the wafer by moving the rotary lifted by the wafer lift pin by the wafer parallel positional relationship near Li Kui rotating rod,
A shutter storage portion for storing the moving shutter;
The moving shutter comprises a heating mechanism, have a metallic flat bottom plate to be heated to a lower side by the heating mechanism of the heating mechanism, the wafer is heated in the heat from the flat bottom plate A plasma processing apparatus heated by radiation . The plasma processing apparatus according to claim 3, wherein the moving shutter includes a temperature sensor and a temperature control mechanism that controls the heating mechanism based on a detection signal of the temperature sensor. The plasma processing apparatus according to claim 3 , wherein the moving shutter has a cooling mechanism above the heating mechanism.

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