JP2004095665A - Electrostatic attraction device and processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic attraction device capable of stably controlling the processing surface temperature of a target to be processed. <P>SOLUTION: An electrostatic chuck 42 is constituted of a dielectric substance 45 and a chuck electrode 46. When DC voltage is impressed to the chuck electrode 46, electrostatic attracting force is generated on 1st and 2nd attracting surfaces 58, 60, a target W to be processed is attracted and held on the 1st attracting surface 58, and the 2nd attracting surface 60 is attracted to a body part 41 of a mounting board. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrostatic attraction apparatus and a processing apparatus, and more particularly to, for example, an electrostatic attraction apparatus for a plasma processing apparatus that suctions and holds a semiconductor processing substrate in a processing space in a plasma atmosphere and performs an etching process on the semiconductor processing substrate. The present invention relates to a plasma processing apparatus.
[0002]
[Prior art]
Vacuum processing techniques including etching and CVD are widely used in the manufacture of semiconductor devices and liquid crystal displays. A typical processing apparatus including these techniques includes an upper electrode and a lower electrode opposed to each other in a processing chamber, and applies a high-frequency power to at least one of the upper electrode and the lower electrode to process the processing chamber. By subjecting the processing gas inside to plasma, the object to be processed mounted on the lower electrode is subjected to plasma processing. The lower electrode functions as a mounting table, and as a configuration of the mounting table for mounting and fixing an object to be processed, an electrostatic chuck (electrostatic chuck) using electrostatic force is known. An electrostatic chuck can electrically hold a workpiece by using Coulomb force or Johnsen-Rahbek force, and the action of the force may depend on the volume resistivity of the dielectric. Are known.
[0003]
FIG. 5 schematically shows a configuration of a lower electrode of a conventional processing apparatus. In FIG. 5, reference numeral 1 indicates a mounting table for the workpiece W. The mounting table 1 has a configuration in which an electrostatic chuck 12 and a ring body 13 provided to surround a side of the electrostatic chuck 12 are provided on an upper surface of the mounting table main body 11. The electrostatic chuck 12 has a configuration in which a sheet-like chuck electrode 14 having conductivity is sandwiched between dielectrics 15, and the upper surface of the mounting table main body 11 (for example, an epoxy resin or a silicone resin adhesive). Mounting surface).
[0004]
The workpiece W can be attracted and held on the chuck surface of the electrostatic chuck 12 by electrostatic force generated by applying a DC voltage (chuck voltage) from the DC power supply 16 to the chuck electrode 14. The dielectric material 15 has a volume resistivity of about 10 ¹⁴ When Ω · cm or more, an electrostatic attraction force is generated due to Coulomb force, and the volume specific resistance is about 10 ¹² Ω · cm-10 ¹⁴ When Ω · cm, Coulomb force and Johnsen-Rahbek force are mixed, and the volume resistivity is about 10 ¹² When it is less than Ω · cm, the electrostatic attraction force due to the Johnsen-Rahbek force becomes dominant.
[0005]
[Problems to be solved by the invention]
When such an electrostatic chuck 12 is used in an environment using a highly corrosive process gas such as a plasma etching apparatus, an adhesive fixing the electrostatic chuck 12 is exposed to a process gas (plasma). Can be eroded. Then, the heat transfer gas supplied between the electrostatic chuck 12 and the object to be processed W and promoting heat exchange between the mounting table 1 and the object to be processed W leaks at the portion where the adhesive has eroded. As a result, a sufficient heat transfer gas is not supplied to the back surface of the processing target W, or heat transfer through the adhesive is not sufficiently performed. There is a problem that the temperature cannot be controlled.
[0006]
The present invention has been made in view of the above problems of the related art, and an object of the present invention is to provide a new and improved electrostatic attraction device capable of stably controlling the processing surface temperature of an object to be processed, and An object of the present invention is to provide a processing device.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a static electricity supply device, which is provided on a mounting surface of a mounting table main body of a mounting table on which a processing object to be subjected to a predetermined process is mounted, and which holds the processing object by electrostatic force. An electroadsorption device, wherein a first dielectric layer constituting a first adsorption surface for adsorbing the object to be processed and a second dielectric surface constituting a second adsorption surface for adhering to the mounting surface of the mounting table body. And a chuck electrode provided between the first dielectric layer and the second dielectric layer.
[0008]
In the electrostatic chuck, the first dielectric layer and the second dielectric layer may be configured so that the volume resistivity of the first dielectric layer is equal to the volume resistivity of the second dielectric layer. Or it is preferable to set it larger.
[0009]
Further, the present invention is an electrostatic attraction device provided on a mounting surface of a mounting table main body of a mounting table on which an object to be processed to be subjected to predetermined processing is mounted, and which holds the object to be processed by electrostatic force. A first dielectric layer forming a first suction surface for sucking the object to be processed, and a second dielectric layer forming a second suction surface for sucking the mounting surface of the mounting table body. A first chuck electrode for generating a suction force on the first suction surface, a second chuck electrode for generating a suction force on the second suction surface, and the first and the second chuck electrodes. And a control means for controlling a voltage applied to the two chuck electrodes.
[0010]
In the electrostatic chuck, the first dielectric layer and the second dielectric layer may be configured so that the volume resistivity of the first dielectric layer is equal to the volume resistivity of the second dielectric layer. Or it is preferable to set it larger. Further, a volume specific resistance value of 10 between the first chuck electrode and the second chuck electrode. ¹⁴ It is preferable that a third dielectric layer of Ω · cm or more is provided.
[0011]
Further, the present invention provides a processing apparatus having the above-described electrostatic suction device, wherein the processing device performs a predetermined process on the processing object in a state where the processing object is suctioned to the electrostatic suction device. provide.
[0012]
As described above, the electrostatic chucking force is generated on the back side of the electrostatic chuck, and the electrostatic chuck is sucked and held on the mounting table main body (mounting surface). The problem is that the heat transfer between the mounting table and the object to be processed cannot be obtained, and the processing surface of the object to be processed cannot be stably controlled to a desired temperature. Does not occur. In addition, since there is no bonding portion due to adhesion, it is possible to increase the temperature of the mounting table and increase the diameter of the object to be processed without being affected by differences in heat capacity and linear expansion. In this case, a desired suction force can be obtained by controlling the volume resistivity of the dielectric layer constituting the suction surface.
[0013]
Further, a first chuck electrode for generating a suction force on the first suction surface and a second chuck electrode for generating a suction force on the second suction surface are provided, and each of the chuck electrodes is provided. By independently controlling the applied voltage, the suction force on the object side and the mounting table side can be individually controlled, and the suction force according to the purpose can be applied to each of the suction surfaces.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a processing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing the entire structure of a magnetron type plasma etching apparatus which is a processing apparatus according to an embodiment of the present invention.
[0015]
In FIG. 1, reference numeral 2 indicates a vacuum chamber forming a processing container. The vacuum chamber 2 is formed of a conductive material such as aluminum so as to form an airtight structure, and is grounded for security. A gas shower head 3 also serving as an upper electrode and a mounting table 4 also serving as a lower electrode are provided in the vacuum chamber 2 so as to face each other. An exhaust pipe 22 is connected as an evacuation passage communicating with evacuation means 21 such as a dry pump.
[0016]
An opening 23 is formed in the side wall of the vacuum chamber 2 for carrying in / out an object to be processed, for example, a wafer W, and can be opened and closed by a gate valve G. Outside the side wall portion, ring-shaped permanent magnets 24 and 25 are provided at positions vertically sandwiching the opening 23. The permanent magnets 24 and 25 are configured as, for example, dipole ring magnets. The gas shower head 3 has a large number of holes 31 formed at positions on the mounting table 4 that face the object W to process the flow-controlled or pressure-controlled processing gas sent from the upper gas supply pipe 32. It is configured to uniformly supply the surface of the processing target W through the holes 31.
[0017]
The mounting table 4 provided below the gas shower head 3 at an interval of about 5 mm to 150 mm is made of, for example, aluminum whose surface is anodized, and is insulated from the vacuum chamber 2 by the insulating member 41a. A column-shaped main body 41, an electrostatic chuck (electrostatic chuck) 42 provided on the upper surface of the main body 41, that is, a mounting surface, an annular focus ring 43 surrounding the periphery of the electrostatic chuck 42, Is provided. The focus ring 43 is made of an insulating or conductive material depending on the process, and acts to confine or diffuse reactive ions.
[0018]
As will be described later, the electrostatic chuck 42 has first and second suction surfaces, generates an electrostatic suction force between the first suction surface and the workpiece W, and generates a second suction surface. An electrostatic attraction force is also generated between the main body 41 (mounting surface) of the mounting table 4 and the main body 41 (mounting surface). That is, the electrostatic chuck 42 generates electrostatic chucking forces having different chucking forces on the front and back sides, and holds the workpiece W on one surface by suction, and the other surface of the main body 41 ( On the mounting surface). That is, the electrostatic chuck 42 is attached to the main body 41 of the mounting table 4 without using an adhesive.
[0019]
A high frequency power supply 40 is connected to, for example, the main body 41 of the mounting table 4 via a capacitor C1 and a coil L1, and high frequency power of, for example, 13.56 MHz to 100 MHz is applied. Thus, a high-frequency electric field is formed in a space between the gas shower head 3 functioning as an upper electrode and the mounting table 4 functioning as a lower electrode. Further, since a horizontal magnetic field is formed in the space by the permanent magnets 24 and 25, a magnetron discharge is generated due to the drift of the electrons, thereby generating a plasma of the processing gas. Further, inside the mounting table 4, there are provided a temperature adjusting means 55a such as a cooling jacket and a heat transfer gas supplying means 55b for supplying, for example, He gas to the back surface of the workpiece W. By activating the heat transfer gas supply unit 55b and the heat transfer gas supply unit 55b, the processing surface temperature of the processing target W held on the mounting table 4 can be set to a desired value. The temperature adjusting means 55a has an inlet pipe 56 and a discharge pipe 57 for circulating the refrigerant through the cooling jacket, and the refrigerant adjusted to an appropriate temperature is supplied into the cooling jacket by the inlet pipe 56, The exchanged refrigerant is discharged to the outside by the discharge pipe 57. Note that a heater, a Peltier element, or the like may be provided in the mounting table 4 instead of the illustrated cooling jacket.
[0020]
An exhaust ring 44 having a plurality of exhaust holes is provided between the mounting table 4 and the vacuum chamber 2 and below the surface of the mounting table 4 (mounting surface) so as to surround the mounting table 4. Placed in The exhaust ring 44 regulates the flow of the exhaust flow and optimally confines the plasma between the mounting table 4 and the gas shower head 3. Further, inside the mounting table 4, a plurality of, for example, three lifting pins 51 (only two are illustrated) are lifted and lowered by a lifting member for transferring the workpiece W to and from a transfer arm (not shown) outside. The lifting pin 51 is provided freely, and is configured to be able to be raised and lowered by a driving mechanism 53 via a connecting member 52. Reference numeral 54 denotes a bellows for maintaining airtightness between the through hole of the elevating pin 51 and the atmosphere side.
[0021]
Next, referring to FIG. 2, the electrostatic chuck 42 which is a main part of the present embodiment will be described in detail.
[0022]
The electrostatic chuck 42 has a configuration in which a foil-like chuck electrode 46 made of, for example, tungsten is sandwiched between dielectric layers 45 made of sintered or spray-formed ceramics. , And can be switched between the DC power supply 47 and the ground. The switching of the switch section SW is controlled by the switch control section 8. Then, as described above, the electrostatic chuck 42 has the first suction surface 58 and the second suction surface 60, and between the first suction surface 58 and the processing target object W and the second suction surface. An electrostatic attraction force is generated between the surface 60 and the main body 41 (mounting surface) of the mounting table 4.
[0023]
The electrostatic attraction force of the first attraction surface 58 and the electrostatic attraction force of the second attraction surface 60 are configured to be individually controllable. The force is configured to be equal to or less than the electrostatic attraction force of the second attraction surface 60.
[0024]
That is, as shown in FIG. 2, the dielectric layer 45 includes a first dielectric layer 45a disposed on the upper surface of the chuck electrode 46 and a second dielectric layer 45a disposed on the lower surface of the chuck electrode 46. 45b, and the first dielectric layer 45a is made of, for example, aluminum oxide (Al ₂ O ₃ ), The volume resistivity value is, for example, 10 ^Fifteen Ω · cm, while the second dielectric layer 45b is made of, for example, aluminum oxide (Al ₂ O ₃ ) Or aluminum nitride (AlN) with titanium dioxide (TiO2). ₂ ), Silicon carbide (SiC) or the like, and has a volume resistivity of, for example, 10%. ¹¹ Ω · cm.
[0025]
In other words, the first dielectric layer 45a on the workpiece W side has a volume resistivity value of 10 ⁸ Ω · cm-10 ^Fifteen A dielectric material of Ω · cm, and a suction force equal to or weaker than the electrostatic suction force of the second suction surface 60 is applied to the first suction surface 58 to hold the workpiece W by suction. I do. It is not necessary to expect the first suction surface 58 to have a high suction force required for the second suction surface 60, and it is preferable to select the suction force according to the type of the workpiece W.
[0026]
On the other hand, the second dielectric layer 45b on the main body 41 side has a volume resistivity value of 10 ¹² It is made of a low-resistance body of less than Ω · cm, and the Johnsen-Rahbek force for obtaining a high suction force is applied to the second suction surface 60 so as to strengthen the adhesion of the mounting table 4 to the main body 41. I have. Therefore, the heat transfer gas supplied to the back surface of the processing object W can be reliably sealed on the back surface side, and the heat transfer between the processing object W and the mounting table 4 can be maintained in a good state. The temperature of W can be controlled with high accuracy. Note that if the suction force of at least one of the suction surfaces 58 and 60 is monitored and the voltage applied to the chuck electrode 46 is varied based on the monitoring result, the expected suction force can be stably maintained. It is possible to obtain.
[0027]
Next, a processing operation in the plasma etching apparatus thus configured will be described.
[0028]
First, the workpiece W is loaded into the vacuum chamber 2 through the gate valve G and the opening 23, placed on the electrostatic chuck 42, and the gate valve G is closed. The inside of the vacuum chamber 2 is evacuated to a predetermined degree of vacuum through 22. Then, a processing gas is supplied into the vacuum chamber 2, and a DC voltage is applied from the DC power supply 47 to the chuck electrode 46, so that the workpiece W is electrostatically attracted by the electrostatic chuck 42.
[0029]
In this state, high-frequency power of a predetermined frequency is applied from the high-frequency power supply 40 to the main body 41 of the mounting table 4, thereby generating a high-frequency electric field in the space between the gas shower head 3 and the mounting table 4. And a horizontal magnetic field formed in this space by the permanent magnets 24 and 25, causing a magnetron discharge due to electron drift, and etching the workpiece W on the electrostatic chuck 42 by the plasma of the processing gas formed thereby. Processing is performed. At this time, the temperature adjusting means 55a and the heat transfer gas supply means 55b are activated, respectively, to circulate the refrigerant in the mounting table 4, and to supply the heat transfer gas to the back surface of the processing object W, and Is controlled to a predetermined temperature.
[0030]
Since such an etching process is performed by a plasma of a corrosive gas, conventionally, an adhesive (layer) fixing the electrostatic chuck 42 to the main body 41 of the mounting table 4 is eroded, and sufficient heat transfer is performed. Is not performed, there is a problem that it is difficult to control the temperature of the object to be processed W. However, according to the embodiment shown in FIG. 1, the electrostatic chuck 42 generates an electrostatic attraction force on the front and back thereof. Since the main body 41 (mounting surface) of the mounting table 4 is adsorbed and held, there is no danger of erosion by plasma, and the temperature of the workpiece W on the electrostatic chuck 42 can be stably controlled. is there.
[0031]
Next, a plasma etching apparatus which is a processing apparatus according to another embodiment will be described in detail with reference to FIGS. The same or similar portions as those in the above-described embodiment are denoted by the same or similar reference numerals, and detailed description thereof will be omitted.
[0032]
The mounting table 4 for holding the workpiece W includes a cylindrical main body 41 insulated from the vacuum chamber 2 by an insulating member 41a, an electrostatic chuck 62 provided on the upper surface of the main body 41, An annular focus ring 43 surrounding the periphery of the chuck 62 is provided.
[0033]
The electrostatic chuck 62 has a configuration in which a foil-like chuck electrode 66 made of, for example, tungsten or the like is sandwiched between dielectric layers 64 made of sintered or spray-formed ceramics. The electrostatic chuck 62 has a first suction surface 58 and a second suction surface 60 as in the embodiment shown in FIG. An electrostatic suction force is generated between each of the second suction surface 60 and the main body 41 (mounting surface) of the mounting table 4. The electrostatic attraction force of the first attraction surface 58 and the electrostatic attraction force of the second attraction surface 60 are configured to be independently controllable. The suction force is configured to be equal to or weaker than the electrostatic suction force of the second suction surface 60.
[0034]
More specifically, referring to FIG. 4, the dielectric layer 64 of the electrostatic chuck 62 has a first dielectric layer 64a, a third dielectric layer 64b, and a second dielectric layer 64c. They are arranged in this order from the body W side. The first chuck electrode 66a is provided between the first dielectric layer 64a and the third dielectric layer 64b, and the second chuck electrode 66a is provided between the third dielectric layer 64b and the second dielectric layer 64c. Chuck electrodes 66b are provided. The first chuck electrode 66a is configured to be switchably connectable between a DC power supply 47a and a ground via a switch SW1, and the second chuck electrode 66b is connected to a DC power 47b via a switch SW2. It is configured so that it can be switched between and connected. Switching between the switch units SW1 and SW2 is performed by the switch control unit 8.
[0035]
The first dielectric layer 64a is made of, for example, aluminum oxide (Al ₂ O ₃ ), And has a volume resistivity of, for example, 10 ¹⁴ Ω · cm, and the third dielectric layer 64b is made of, for example, aluminum oxide (Al ₂ O ₃ ), And has a volume resistivity of, for example, 10 ^Fifteen Ω · cm, and the second dielectric layer 64c is made of, for example, aluminum oxide (Al ₂ O ₃ ) Or aluminum nitride (AlN) with titanium dioxide (TiO2). ₂ ), Silicon carbide (SiC) or the like, and has a volume resistivity of, for example, 10%. ¹¹ Ω · cm.
[0036]
That is, the first dielectric layer 64a on the processing target W side has a volume resistivity value of 10 ⁸ Ω · cm-10 ^Fifteen A dielectric material of Ω · cm, and a suction force equal to or weaker than the electrostatic suction force of the second suction surface 60 is applied to the first suction surface 58 to hold the workpiece W by suction. I do. It is not necessary to expect the first suction surface 58 to have a high suction force as required by the second suction surface 60, and it is preferable to select the suction force according to the type of the workpiece W.
[0037]
On the other hand, the second dielectric layer 64c on the main body 41 side has a volume resistivity value of 10 ¹² A low resistance element having a resistance of less than Ω · cm, and a Johnsen-Rahbek force capable of obtaining a high attraction force is applied to the second attraction surface 60, and the adhesion to the main body portion 41 (mounting surface) of the mounting table 4. Is strong. Therefore, the heat transfer gas supplied to the back surface of the processing object W can be reliably sealed on the back surface, and the heat transfer between the processing object W and the mounting table 4 can be maintained well, and the processing object W Can be temperature controlled with high accuracy.
[0038]
The third dielectric layer 64b disposed between the first chuck electrode 66a and the second chuck electrode 66b has a volume specific resistance of 10 ¹⁴ Ω · cm or more, preferably 10 ^Fifteen It is composed of a dielectric material of Ω · cm or more. Therefore, the first chuck electrode 66a and the second chuck electrode 66b are electrically isolated.
[0039]
On the other hand, the DC power supplies 47a and 47b are variable power supplies, and the values of these voltages are individually controlled by the voltage control unit 68, whereby the electrostatic attraction force of the first attraction surface 58 and the second attraction force are reduced. The electrostatic attraction force of the attraction surface 60 is controlled independently. That is, as described above, in addition to adjusting the attraction force by adjusting the volume specific resistance of each of the dielectric layers constituting the attraction surface, by controlling the voltage values of the DC power supplies 47a and 47b, the processing object side and the mounting table are controlled. The suction force on the side can be individually controlled to apply the suction force according to the purpose to each of the suction surfaces.
[0040]
The attraction force of at least one of the first suction surface 58 and the second suction surface 60 is monitored and applied to the first chuck electrode 66a or the second chuck electrode 66b based on the monitoring result. If the voltage is configured to be variable, it is possible to stably obtain an expected suction force.
[0041]
In the present embodiment, the distance between the first suction surface 58 and the first chuck electrode 66a is 250 μm, the distance between the first chuck electrode 66a and the second chuck electrode 66b is 450 μm, and the distance between the first chuck electrode 66a and the second chuck electrode 66b is 450 μm. It is preferable that the distance between 66b and the second suction surface 60 be set to 250 μm, respectively, and the first dielectric layer 64a and the second dielectric layer 64c be set thin enough to prevent dielectric breakdown.
[0042]
As described above, according to the present embodiment, since the electrostatic chuck is fixed to the main body (mounting surface) of the mounting table by the electrostatic attraction force without using the adhesive, the bonding is performed by plasma. Problems such as the expected heat transfer not being obtained due to the erosion of the agent can be solved. In addition, since there is no bonding portion due to adhesion, it is possible to increase the temperature of the mounting table and increase the diameter of the object to be processed without being affected by differences in heat capacity and linear expansion.
[0043]
In addition, the volume resistivity of the dielectric layer constituting the suction surface is controlled individually, and the voltage applied to each of the chuck electrodes is independently controlled, so that the suction force on the object side and the mounting table side are individually controlled. , It is possible to apply a suction force according to the purpose to each suction surface. Further, since the electrostatic chuck is configured to be detachable, cost reduction and improvement in maintainability can be achieved.
[0044]
In the above-described embodiment, the description has been given of the monopolar electrostatic chuck. However, the present invention is also applied to a bipolar electrostatic chuck that arranges a plurality of chuck electrodes in a substantially horizontal direction and applies a voltage between the electrodes. It goes without saying that you can do it. Further, in the above-described embodiment, the description has been given by taking as an example the case where the chuck electrode is in the form of a foil. However, the present invention is not limited to this. For example, the chuck electrode may be formed in a ring shape to positively prevent the leakage of heat transfer gas. Alternatively, a chuck electrode configured to perform the above operation may be used.
[0045]
Further, in the above-described embodiment, the magnetron type plasma etching apparatus using the permanent magnet is illustrated, but a parallel plate type plasma processing apparatus without the permanent magnet may be used. Further, the case where the lower electrode holding the object to be processed W and the upper electrode facing the lower electrode are arranged in parallel in the vertical direction has been described as an example, but the present invention is not limited thereto. Also, the present invention can be applied to a processing apparatus in which two electrodes are horizontally separated from each other. Also, the processing device configured to apply high-frequency power to the lower electrode has been described as an example. However, a processing device that applies high-frequency power only to the upper electrode, or high-frequency power is applied to both the upper electrode and the lower electrode. The present invention can also be applied to a processing device that performs processing.
[0046]
Furthermore, in the above-described embodiment, a parallel plate type plasma etching apparatus has been described as an example. However, the present invention is not limited to such a configuration, and can be applied to other plasma processing apparatuses such as an inductive coupling type. Further, the present invention can be applied not only to plasma etching processing but also to various processing apparatuses such as ashing processing and film forming processing. Furthermore, the present invention is suitable for an apparatus using a semiconductor substrate or a glass substrate for an LCD as an object to be processed, but the object to which the present invention can be applied is not limited to these.
[0047]
【The invention's effect】
As described above, according to the present invention, an electrostatic chucking force is generated on the back side of the electrostatic chuck, and the electrostatic chuck is sucked and held on the mounting table body (mounting surface). As a result, the adhesive fixing the electrostatic chuck is deteriorated, and the expected heat transfer between the mounting table and the processing target is not obtained, and the processing surface of the processing target is stably maintained at a desired temperature. The problem that the control cannot be performed in a short time does not occur. In addition, since there is no bonding portion due to adhesion, it is possible to increase the temperature of the mounting table and increase the diameter of the object to be processed without being affected by differences in heat capacity and linear expansion.
[0048]
Further, a first chuck electrode for generating a suction force on the first suction surface and a second chuck electrode for generating a suction force on the second suction surface are provided, and each of the chuck electrodes is provided. By independently controlling the applied voltage, the suction force on the object side and the mounting table side can be individually controlled, and the suction force according to the purpose can be applied to each of the suction surfaces.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an embodiment of a plasma etching apparatus according to the present invention.
FIG. 2 is a schematic enlarged sectional view showing an electrostatic chuck of the plasma etching apparatus shown in FIG.
FIG. 3 is a longitudinal sectional view showing another embodiment of the plasma etching apparatus.
FIG. 4 is a schematic enlarged sectional view showing an electrostatic chuck of the plasma etching apparatus shown in FIG. 3;
FIG. 5 is a longitudinal sectional view showing an electrostatic chuck of a processing apparatus according to the related art.
[Explanation of symbols]
W Workpiece
2 Vacuum chamber
3 gas shower head
4 Mounting table
41 Main unit
42 Electrostatic chuck
45 Dielectric
45a first dielectric layer
45b Second dielectric layer
46 chuck electrode
47, 47a, 47b DC power supply
51 Lifting pin
58 First suction surface
60 Second suction surface
62 Electrostatic chuck
64 dielectric
64a First dielectric layer
64b Third dielectric layer
64c Second dielectric layer
66 chuck electrode
66a first chuck electrode
66b second chuck electrode
68 Voltage controller

Claims (6)

An electrostatic adsorption device is provided on a mounting surface of a mounting table main body of a mounting table for mounting an object to be processed on which predetermined processing is performed, and suction-holds the object to be processed by electrostatic force,
A first dielectric layer constituting a first adsorption surface for adsorbing the object,
A second dielectric layer constituting a second suction surface that is sucked to the mounting surface of the mounting table body;
A chuck electrode provided between the first dielectric layer and the second dielectric layer;
An electrostatic attraction device comprising: The first dielectric layer and the second dielectric layer may have a volume resistivity of the first dielectric layer equal to or greater than a volume resistivity of the second dielectric layer. The electrostatic attraction device according to claim 1, wherein the electrostatic attraction device is set to be larger than the above. An electrostatic adsorption device is provided on a mounting surface of a mounting table main body of a mounting table for mounting an object to be processed on which predetermined processing is performed, and suction-holds the object to be processed by electrostatic force,
A first dielectric layer constituting a first adsorption surface for adsorbing the object,
A second dielectric layer constituting a second suction surface that is sucked to the mounting surface of the mounting table body;
A first chuck electrode for generating a suction force on the first suction surface;
A second chuck electrode for generating a suction force on the second suction surface;
Control means for controlling a voltage applied to the first and second chuck electrodes;
An electrostatic attraction device comprising: The first dielectric layer and the second dielectric layer may have a volume resistivity of the first dielectric layer equal to or greater than a volume resistivity of the second dielectric layer. The electrostatic attraction device according to claim 3, wherein the electrostatic attraction device is set to be larger than the above. 4. The device according to claim 3, wherein a third dielectric layer having a volume resistivity of 10 ¹⁴ Ω · cm or more is provided between the first chuck electrode and the second chuck electrode. 5. The electrostatic attraction device according to 4. 6. The apparatus according to claim 1, wherein the processing unit performs a predetermined process on the workpiece while the workpiece is attracted to the electrostatic suction apparatus. Processing equipment.

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