JP6428456B2 - Electrostatic chuck device - Google Patents

Description

  The present invention relates to an electrostatic chuck device.

  2. Description of the Related Art Conventionally, in a semiconductor manufacturing apparatus using plasma such as a plasma etching apparatus and a plasma CVD apparatus, an electrostatic chuck apparatus is used as an apparatus for simply mounting and fixing a wafer on a sample stage and maintaining the wafer at a desired temperature. Is used.

As such an electrostatic chuck device, for example, a ceramic base in which a plate electrode for electrostatic adsorption is embedded inside, and a base portion in which a refrigerant flow path for refrigerant circulation is formed inside are used as an adhesive layer. Are known to be joined and integrated (for example, Patent Document 1).
With the recent increase in semiconductor diameter and pattern miniaturization, characteristics required for electrostatic chuck devices are also increasing.
In Patent Document 2, even if force is applied to the semiconductor manufacturing apparatus side terminal by improving the shape of the electrode of the electrostatic chuck that penetrates the base portion and is connected to the electrode of the ceramic substrate, the influence of the force is influenced by the ceramic. It is described that it does not reach the substrate.
Patent Document 3 describes that the adhesive layer is made uniform by using a low-viscosity thermosetting adhesive as an adhesive for bonding the ceramic substrate and the base portion in order to improve the thermal uniformity of the adsorption surface.

JP 2004-31665 A JP 2013-191626 A JP 2011-82405 A

  The electrostatic chuck device adheres the base portion, the ceramic base, and these by a heater provided to keep the temperature of the mounting surface on which the wafer is placed, plasma heating, a cooling function of the base portion, and the like. The adhesive layer expands or contracts. Due to the difference in coefficient of thermal expansion of these members, stress may be generated in the electrode that penetrates the base portion and is connected to the ceramic base, and the connection portion of the electrode may be damaged.

  The present invention has been made in view of the above-described problems, and prevents damage by preventing stress from being applied to the tip portion of the electrode pin that is inserted through the cooling base portion and connected to the electrostatic chuck portion. An object of the present invention is to provide an electrostatic chuck device with improved performance.

  An electrostatic chuck apparatus according to the present invention includes a first surface on which a plate-like sample is placed and a second surface opposite to the first surface, and an electrostatic chuck portion including an internal electrode for electrostatic adsorption, A cooling base portion disposed on the second surface side for cooling the electrostatic chuck portion; a resin layer interposed between and bonded to the electrostatic chuck portion and the cooling base portion; and the electrostatic chuck portion A heating member fixed to the second surface, an electrode pin that is inserted through a through hole that penetrates the cooling base portion in the thickness direction, and has a tip connected to the heating member, and an outer periphery of the electrode pin And an outer peripheral resin layer extending from the resin layer between the inner periphery of the through hole and the outer periphery of the stress relaxation layer.

According to this configuration, even if the electrostatic chuck portion and the resin layer are displaced due to the difference in thermal expansion coefficient due to the stress relaxation layer provided on the outer periphery of the electrode pin. The stress applied to the electrode pin can be relaxed. Therefore, it is possible to prevent the electrode pin and the connection portion between the electrode pin and the heating member from being damaged.
By the way, when using a highly flexible resin as the stress relaxation layer, there is a concern that the thermal conductivity of the stress relaxation layer is lowered. As a result, the electrostatic chuck portion in contact with the stress relaxation layer is not sufficiently cooled by the cooling base portion, and there is a possibility that the thermal uniformity of the electrostatic chuck portion is hindered.
According to the above configuration, the outer peripheral resin layer is formed in which the resin layer extends between the inner periphery of the through hole and the stress relaxation layer. This outer peripheral resin layer can play a role of transferring heat from the outer periphery of the stress relaxation layer to the cooling base portion. Therefore, the stress relieving layer is efficiently cooled, and the region in contact with the stress relieving layer of the electrostatic chuck portion can be efficiently cooled, so that the thermal uniformity of the electrostatic chuck portion can be improved.

  The electrostatic chuck device according to the embodiment has a first surface on which a plate-like sample is placed and a second surface opposite to the first surface, and includes an electrostatic chuck internal electrode. A cooling base portion disposed on the second surface side for cooling the electrostatic chuck portion, a resin layer interposed between and bonded to the electrostatic chuck portion and the cooling base portion, and the static An internal electrode terminal connected to the internal electrode for electroadsorption and exposed from the second surface of the electrostatic chuck portion, and a through-hole penetrating the cooling base portion in the thickness direction are inserted into the internal electrode terminal. An electrode pin having a tip connected thereto, a stress relaxation layer provided on the outer periphery of the electrode pin, and an outer peripheral resin layer extending from the resin layer between the inner periphery of the through hole and the outer periphery of the stress relaxation layer .

According to this structure, the stress to the electrode pin due to the difference in thermal expansion coefficient can be relaxed by the stress relaxation layer. Therefore, it is possible to prevent the electrode pin and the connection portion between the electrode pin and the internal electrode terminal from being damaged.
Moreover, according to the said structure, by providing the outer periphery resin layer, a stress relaxation layer can be cooled efficiently and the thermal uniformity of an electrostatic chuck part can be improved.

In the electrostatic chuck device, the stress relaxation layer may be formed of a material that is more flexible than the outer peripheral resin layer.
According to this configuration, the stress relaxation layer can relieve the elastic deformation force generated by the deformation of the outer peripheral resin layer and reduce the load applied to the electrode pin.

  In the above electrostatic chuck device, the Young's modulus of the stress relaxation layer may be 1 MPa or less.

  The electrostatic chuck device may include an insulating shielding tube disposed between the stress relaxation layer and the outer peripheral resin layer so as to surround the electrode pin.

  The electrostatic chuck device according to the embodiment has a first surface on which a plate-like sample is placed and a second surface opposite to the first surface, and includes an electrostatic chuck internal electrode. A cooling base portion disposed on the second surface side for cooling the electrostatic chuck portion, a resin layer interposed between and bonded to the electrostatic chuck portion and the cooling base portion, and the static A heating member fixed to the second surface of the electric chuck portion, an electrode pin having a tip connected to the heating member through a through hole penetrating the cooling base portion in the thickness direction, and the resin layer It has an outer peripheral resin layer that extends to the inner periphery of the through hole and is formed on the outer periphery of the electrode pin via a gap.

According to this configuration, since the gap is provided on the outer periphery of the electrode pin, even if the positional deviation occurs between the electrostatic chuck portion and the resin layer due to the difference in thermal expansion coefficient, the electrode No stress is applied to the pin. Therefore, it is possible to prevent the electrode pin and the connection portion between the electrode pin and the heating member from being damaged.
In the electrostatic chuck device having the above-described configuration, the outer peripheral resin layer is formed around the electrode pin via a gap. The outer peripheral resin layer exchanges heat with the cooling base portion on the inner peripheral surface of the through hole of the cooling base portion. Therefore, the cooling efficiency of the resin layer around the voids is improved as compared with other portions. Therefore, even in the vicinity of the gap in the electrostatic chuck portion, the cooling can be performed in the same manner as other portions, and the thermal uniformity of the electrostatic chuck portion can be ensured.

  The electrostatic chuck device according to the embodiment has a first surface on which a plate-like sample is placed and a second surface opposite to the first surface, and includes an electrostatic chuck internal electrode. A cooling base portion disposed on the second surface side for cooling the electrostatic chuck portion, a resin layer interposed between and bonded to the electrostatic chuck portion and the cooling base portion, and the static An internal electrode terminal connected to the internal electrode for electroadsorption and exposed from the second surface of the electrostatic chuck portion, and a through-hole penetrating the cooling base portion in the thickness direction are inserted into the internal electrode terminal. An electrode pin having a tip connected thereto, and an outer peripheral resin layer extending from the resin layer to the inner periphery of the through hole and formed on the outer periphery of the electrode pin via a gap.

According to this configuration, since the gap is provided on the outer periphery of the electrode pin, even if the positional deviation occurs between the electrostatic chuck portion and the resin layer due to the difference in thermal expansion coefficient, the electrode No stress is applied to the pin. Therefore, it is possible to prevent the electrode pin and the connection portion between the electrode pin and the internal electrode terminal from being damaged.
Moreover, according to the said structure, by providing the outer periphery resin layer, the cooling efficiency of the resin layer around a space | gap can be improved, and the thermal uniformity of an electrostatic chuck part can be ensured.

  The electrostatic chuck device may include an insulating shielding tube that is fixed to the inner periphery of the outer peripheral resin layer and disposed so as to surround the electrode pin.

  According to the electrostatic chuck device of the present invention, since the stress relaxation layer is provided on the outer periphery of the tip portion of the electrode pin, the stress applied to the tip portion of the electrode pin is suppressed and the tip portion of the electrode pin is damaged. It can be prevented from occurring. In addition, since the outer peripheral layer is provided between the through hole and the stress relaxation layer, it is possible to ensure the thermal uniformity of the electrostatic chuck portion.

FIG. 1A is a cross-sectional view showing the electrostatic chuck device of the first embodiment, and FIG. 1B is an enlarged view of a region A shown in FIG. It is a top view which shows an example of the arrangement | positioning pattern of the heating member of the electrostatic chuck apparatus of 1st Embodiment. It is sectional drawing which shows the electrostatic chuck apparatus of 2nd Embodiment. It is sectional drawing which shows the electrostatic chuck apparatus of 3rd Embodiment.

  Embodiments of the electrostatic chuck device will be described below with reference to the drawings. In the drawings used in the following description, for the purpose of emphasizing the feature portion, the feature portion may be shown in an enlarged manner for convenience, and the dimensional ratios of the respective constituent elements are not always the same as in practice. Absent. In addition, for the same purpose, portions that are not characteristic may be omitted from illustration.

<< First Embodiment >>
FIG. 1A is a cross-sectional view showing the electrostatic chuck device 100 of the first embodiment. Moreover, FIG.1 (b) is an enlarged view of the area | region A of Fig.1 (a).
The electrostatic chuck device 100 includes a disk-shaped electrostatic chuck unit 20 on which a plate-shaped sample W is installed, a disk-shaped cooling base unit 50 that cools the electrostatic chuck unit 20, and these are bonded and integrated. And a resin layer 80 to be used. In other words, the electrostatic chuck device 100 has a structure in which the cooling base portion 50, the resin layer 80, and the electrostatic chuck portion 20 are laminated in this order in the + Z direction (height direction) in FIG.

The electrostatic chuck portion 20 has a first surface 20a on which the plate-like sample W is placed and a second surface 20b on the opposite side. An adhesive 6 and a heating member (heater element) 7 are provided on the second surface 20b.
The electrostatic chuck 20 has an electrostatic chucking internal electrode 23 and an internal electrode terminal 24 extending from the electrostatic chucking internal electrode 23 in the thickness direction of the electrostatic chuck 20.

The cooling base unit 50 includes a first surface 50 a that faces the electrostatic chuck unit 20, and a second surface 50 b that is the opposite side and serves as a mounting surface of the electrostatic chuck device 100.
The cooling base unit 50 includes first and second through holes 51 and 52 that penetrate in the thickness direction. An insulating tube (insulator) 15 is embedded in each of the first and second through holes 51 and 52. Each insulating tube 15 includes first and second power feeding structures 30 and 40, respectively.

  The first power supply structure 30 includes a connection terminal 32, a connection line 33, an electrode pin 31, a stress relaxation layer 34, and a shielding tube 37. The second power supply structure 40 includes a connection terminal 42, a connection wire 43, an electrode pin 41, a stress relaxation layer 44 and a shielding tube 47.

Hereinafter, the configuration of each part will be described in detail with reference to FIGS. 1 (a) and 1 (b).
<Electrostatic chuck>
The electrostatic chuck unit 20 includes a mounting plate 21 on which a plate-like sample W such as a semiconductor wafer, a metal wafer, or a glass substrate is installed, a support plate 22 disposed opposite to the mounting plate 21, and a mounting plate 21. It has an internal electrode 23 for electrostatic attraction sandwiched between support plates 22 and an internal electrode terminal 24 embedded in the support plate 22.

The mounting plate 21 and the support plate 22 have a disk shape with the same shape of the superimposed surfaces, and are an aluminum oxide-silicon carbide (Al ₂ O ₃ —SiC) composite sintered body, aluminum oxide (Al _2). Insulating ceramics having mechanical strength, corrosive gas and durability against plasma, such as O ₃ ) sintered body, aluminum nitride (AlN) sintered body, yttrium oxide (Y ₂ O ₃ ) sintered body It is preferable to consist of a sintered body.
Moreover, it is good also as a cheap structure by making the mounting board 21 into said ceramic sintered compact and making the support plate 22 into insulating resin, such as a polyimide.

A plurality of protrusions 26 having a diameter smaller than the thickness of the plate-like sample W are formed on the first surface 20 a on which the plate-like sample W is placed, which is one surface of the mounting plate 21. These protrusions 26 are configured to support the plate-like sample W.
The support plate 22 is provided with a hole 22a penetrating in the thickness direction. The internal electrode terminal 24 is inserted through the hole 22a.

The thickness of the electrostatic chuck portion 20 is preferably 0.7 mm or more and 5.0 mm or less. When the thickness of the electrostatic chuck portion 20 is less than 0.7 mm, the mechanical strength of the electrostatic chuck portion 20 cannot be ensured. On the other hand, if the thickness of the electrostatic chuck portion 20 exceeds 5.0 mm, the heat capacity of the electrostatic chuck portion 20 becomes too large, the thermal response of the plate-like sample W to be placed deteriorates, and further, Due to the increase in the lateral heat transfer of the electric chuck portion 20, it becomes difficult to maintain the in-plane temperature of the plate-like sample W in a desired temperature pattern.
In particular, the thickness of the mounting plate 21 is preferably 0.3 mm or more and 2.0 mm or less. If the thickness of the mounting plate 21 is less than 0.3 mm, the risk of discharge due to the voltage applied to the internal electrode 23 for electrostatic attraction increases. On the other hand, if it exceeds 2.0 mm, the plate-like sample W cannot be sufficiently adsorbed and fixed, and it becomes difficult to sufficiently heat the plate-like sample W.

The internal electrode 23 for electrostatic adsorption is used as an electrode for an electrostatic chuck for generating an electric charge and fixing the plate-like sample W with electrostatic adsorption force. Adjust as appropriate.
The material of the internal electrode 23 for electrostatic attraction is selected in consideration of the difference in thermal expansion from the materials used for the mounting plate 21 and the support plate 22 and heat resistance. For example, the internal electrode 23 for electrostatic adsorption includes an aluminum oxide-tantalum carbide (Al ₂ O ₃ —Ta ₄ C ₅ ) conductive composite sintered body, an aluminum oxide-tungsten (Al ₂ O ₃ —W) conductive composite sintered body. Combined body, aluminum oxide-silicon carbide (Al ₂ O ₃ -SiC) conductive composite sintered body, aluminum nitride-tungsten (AlN-W) conductive composite sintered body, aluminum nitride-tantalum (AlN-Ta) conductive Conductive ceramics such as composite sintered bodies, yttrium oxide-molybdenum (Y ₂ O ₃ -Mo) conductive composite sintered bodies, or refractory metals such as tungsten (W), tantalum (Ta), molybdenum (Mo) Alternatively, silver (Ag), carbon (C), or the like can be used.

The thickness of the electrostatic adsorption internal electrode 23 is not particularly limited, but is preferably 0.1 μm or more and 100 μm or less, and particularly preferably 5 μm or more and 20 μm or less.
If the thickness is less than 0.1 μm, sufficient electrical conductivity cannot be ensured. On the other hand, if the thickness exceeds 100 μm, the electrostatic chucking internal electrode 23 is placed between the mounting plate 21 and the support plate 22. This is because cracks are likely to occur at the bonding interface between the electrostatic adsorption internal electrode 23 and the mounting plate 21 and the support plate 22 due to the difference in thermal expansion coefficient.
The electrostatic adsorption internal electrode 23 having such a thickness can be easily formed by a film forming method such as sputtering or vapor deposition, or a coating method such as screen printing.

The internal electrode terminal 24 is provided to apply a DC voltage to the electrostatic adsorption internal electrode 23. The internal electrode terminal 24 extends through the hole 22a from the internal electrode 23 for electrostatic attraction and extends in the thickness direction, and is exposed to the second surface 20b of the electrostatic chuck portion 20.
The material of the internal electrode terminal 24 is not particularly limited as long as it is a conductive material excellent in heat resistance, but the thermal expansion coefficient is close to the thermal expansion coefficients of the electrostatic adsorption internal electrode 23 and the support plate 22. Is preferred. For example, a conductive ceramic constituting the internal electrode 23 for electrostatic adsorption or a metal material such as tungsten (W), tantalum (Ta), molybdenum (Mo), niobium (Nb), Kovar alloy, or the like is preferably used. It is done.

<Heating member>
The heating member 7 is arranged in a predetermined pattern on the second surface 20 b of the electrostatic chuck portion 20 via the adhesive material 6.
FIG. 2 shows an example of an arrangement pattern of the heating members 7 formed on the second surface 20b. The heating member 7 includes two heaters (an inner heater 7a and an outer heater 7b) that are independent of each other. The inner heater 7a is formed at the center of the second surface 20b, and the outer heater 7b is a peripheral portion of the second surface 20b and is formed in an annular shape outside the inner heater 7a.

Each of the inner heater 7a and the outer heater 7b is a heater pattern made of a metal material meandering in a strip shape, and is disposed on the entire second surface 20b.
The electrode pins 31 shown in FIG. 1 are connected to the terminal portions 8 of the inner heater 7a and the outer heater 7b. The inner heater 7a and the outer heater 7b generate heat due to the current supplied from the electrode pins 31.
The arrangement pattern of the heating members 7 may be constituted by two or more heater patterns independent from each other as described above, but may be constituted by one heater pattern. However, as in the present embodiment, by configuring with a plurality of mutually independent heaters (inner heater 7a, outer heater 7b), the inner heater 7a and outer heater 7b are individually controlled, and the mounting plate 21 The in-plane temperature distribution of the plate-like sample W fixed to the placement surface by electrostatic adsorption can be controlled freely and accurately.

The heating member 7 has a constant thickness of 0.2 mm or less, preferably 0.1 mm or less.
If the thickness of the heating member 7 exceeds 0.2 mm, the pattern shape of the heating member 7 is reflected as the temperature distribution of the plate sample W, and it is difficult to maintain the in-plane temperature of the plate sample W in a desired temperature pattern. become.
Further, by setting the heating member 7 to a constant thickness, the amount of heat generated by the heating member 7 can also be made constant over the entire heating surface. Thereby, temperature distribution in the 1st surface 20a of electrostatic chuck part 20 can be made uniform.

The heating member 7 is preferably made of a non-magnetic metal thin plate. For example, a titanium (Ti) thin plate, a tungsten (W) thin plate, a molybdenum (Mo) thin plate, or the like is etched into a desired heater pattern by photolithography. Can be formed.
By forming the heating member 7 from a nonmagnetic metal, the heating member 7 does not self-heat due to the high frequency even when the electrostatic chuck device 100 is used in a high frequency atmosphere. Therefore, it is easy to maintain the in-plane temperature of the plate-like sample W at a desired constant temperature or a constant temperature pattern even in a high-frequency atmosphere.

The adhesive 6 is provided to bond the heating member 7 to the second surface 20 b of the electrostatic chuck portion 20 and has the same pattern shape as the heating member 7.
The adhesive 6 is a sheet-like or film-like adhesive resin, and preferably has heat resistance and insulation, and a polyimide resin, a silicone resin, an epoxy resin, or the like can be employed.
The thickness of the adhesive 6 is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or more and 50 μm or less. The in-plane thickness variation of the adhesive 6 is preferably within 10 μm. If the in-plane thickness variation of the adhesive 6 exceeds 10 μm, the in-plane spacing between the electrostatic chuck unit 20 and the heating member 7 will exceed 10 μm. As a result, the in-plane uniformity of the heat transmitted from the heating member 7 to the electrostatic chuck unit 20 is lowered, and the in-plane temperature on the mounting surface of the electrostatic chuck unit 20 may be non-uniform.

<Cooling base part>
The cooling base part 50 is for adjusting the electrostatic chuck part 20 to a desired temperature, and has a thick disk shape.
As the cooling base unit 50, for example, a liquid cooling base in which a flow path (not shown) for circulating a refrigerant is formed is suitable.
The material constituting the cooling base portion 50 is not particularly limited as long as it is a metal excellent in thermal conductivity, conductivity, and workability, or a composite material containing these metals. For example, aluminum (Al), aluminum alloy , Copper (Cu), copper alloy, stainless steel (SUS) and the like are preferably used. It is preferable that at least the surface of the cooling base portion 50 exposed to plasma is anodized or an insulating film such as alumina is formed.
Further, an insulating resin sheet such as polyimide may be attached to the first surface 50a of the cooling base portion 50 facing the electrostatic chuck portion 20 to improve the withstand voltage characteristics.

The cooling base portion 50 is provided with first and second through holes 51 and 52, and an insulating tube 15 is attached to each of them. A first power supply structure 30 that supplies power to the heating member 7 is inserted into the first through hole 51. The second feed structure portion 40 that feeds power to the internal electrode terminal 24 is inserted into the second through hole 52.
In addition, the cooling base portion 50 has a through hole for inserting a lift pin for pushing up the wafer in the processing step of the plate-like sample W, and a cooling gas supplied between the plate-like sample W and the electrostatic chuck portion 20. A plurality of through holes are provided in accordance with the purpose such as a through hole for supplying water.

<Insulation tube>
The insulating tube 15 is embedded in the first and second through holes 51 and 52, respectively. The insulating tube 15 includes first and second power feeding structures 30 and 40 for supplying power to the heating member 7 or the internal electrode terminal 24.
The material of the insulating tube 15 may be made of resin or ceramics, but is preferably made of ceramics in terms of heat conduction, heat resistance, withstand voltage, dimensional accuracy, cost, and aluminum oxide. It can be suitably employed.
Further, instead of the insulating tube 15, an insulating film is formed on the inner peripheral surfaces of the first and second through holes 51, 52 to cool the first and second power feeding structures 30, 40. The base unit 50 may be insulated from each other.

The inner diameter of the insulating tube 15 is preferably 5 mm or more and 15 mm or less, for example. By setting the inner diameter of the insulating tube 15 to 15 mm or less, the heat uniformity around the insulating tube 15 can be secured. In addition, by setting the inner diameter of the insulating tube 15 to 5 mm or more, it is possible to secure a sufficient work space for configuring the first and second feeding structure portions 30 and 40 inside the insulating tube 15.
The thickness of the insulating tube 15 is preferably 0.5 mm or more and 2.5 mm or less, for example. By setting the thickness of the insulating tube 15 to 2.5 mm or less, the thermal uniformity around the insulating tube 15 can be ensured. Further, by setting the thickness of the insulating tube 15 to 0.5 mm or more, the insulating tube 15 can have sufficient strength and can be prevented from being damaged during assembly.

  The insulating tube 15 is fixed to the through holes 51 and 52 of the cooling base 50 using an adhesive (not shown). Alternatively, the insulating tube 15 may be fitted and attached to the through holes 51 and 52 in a state where grease having a high thermal conductivity is filled. In any case, it is preferable to attach so that no gap is generated between the inner peripheral surface of the through holes 51 and 52 and the outer peripheral surface of the insulating tube 15. Thereby, the heat distribution of the insulating tube 15 and the surrounding cooling base part 50 can be made uniform.

  The upper end 15b on the + Z side of the insulating tube 15 is preferably a continuous flat surface (flat) without protruding from the first surface 50a of the cooling base 50. By making the upper end 15b of the insulating tube 15 and the upper end of the cooling base portion 50 flush with each other, bubbles are unlikely to form in the resin layer 80 when the resin layer 80 is formed on the first surface 50a side of the cooling base portion 50. The resin layer 80 can have uniform thermal characteristics.

<Power supply structure>
The first power feeding structure 30 includes a connection terminal 32, a connection line 33, an electrode pin 31, a stress relaxation layer 34, and a shielding tube 37. The electrode pins 31 of the first power supply structure unit 30 are connected to the terminal unit 8 of the heating member 7.
Similarly, the second power supply structure 40 includes a connection terminal 42, a connection line 43, an electrode pin 41, a stress relaxation layer 44, and a shielding tube 47. The electrode pin 41 of the second power feeding structure portion 40 is connected to the exposed portion 24 a of the internal electrode terminal 24 exposed from the second surface 20 b of the electrostatic chuck portion 20.
The first power supply structure unit 30 and the second power supply structure unit 40 have the same configuration, and the following description will be made based on FIG. The 2nd electric power feeding structure part 40 has the same structure as the 1st electric power feeding structure part 30, and there exists the same effect except the case where it describes specially.

<Electrode pin>
The electrode pin 31 has a flange portion 31b provided on the tip end surface 31a side (+ Z side) connected to the heating member 7, and a columnar portion 31c erected from the flange portion 31b. A connecting line 33 is connected to a lower end portion 31d of the end of the cylindrical portion 31c on the side opposite to the flange portion 31b of the electrode pin 31 (−Z side).
The length of the electrode pin 31 is preferably 3 mm or more and 10 mm or less, for example. The electrode pin 31 may be connected to the connecting wire 33 by welding or soldering while being connected to the heating member 7. In such a case, by setting the length of the electrode pin 31 to 3 mm or more, heat for melting the welding or solder becomes difficult to be transmitted to the adhesive 6, and the deterioration of the adhesive 6 due to heat is suppressed. it can.
The cylindrical portion 31c of the electrode pin 31 may be divided into a male screw portion and a female screw portion, and the connection line 33 may be sandwiched between the male screw portion and the female screw portion for connection.

  For example, the outer diameter of the cylindrical portion 31c is preferably 1.5 mm or more and 5 mm or less. By setting the outer diameter of the cylindrical portion 31c to 5 mm or less, the first power feeding structure portion 30 can be downsized, and the through hole 51 can be reduced in diameter. Thereby, the soaking | uniform-heating property of the cooling base part 50 can be improved. Further, by setting the outer diameter of the cylindrical portion 31c to 1.5 mm or more, the electric resistance of the electrode pin 31 can be made sufficiently small to prevent the electrode pin 31 from generating heat.

The outer diameter of the flange portion 31b is preferably 1.5 times or more the outer diameter of the cylindrical portion 31c, for example, preferably 4 mm or more and 14 mm or less.
By setting the outer diameter of the flange portion 31b to 4 mm or more and 14 mm or less, it is possible to secure a necessary and sufficient welding area when joining the tip surface 31a of the electrode pin 31 and the heating member 7.
The thickness of the flange 31b is preferably 0.1 mm or more and 0.5 mm or less, for example. By setting the flange portion 31b to 0.5 mm or less, the stress relaxation layer 34 formed on the outer periphery of the electrode pin 31 can enter between the flange portion 31b and the shielding tube 37 without any gap and form a uniform layer.

The material of the electrode pin 31 is a metal or a composite of metal and ceramic, and is preferably the same material as the material of the heating member 7 or a composite material of the same material as the material of the heating member 7 and another material.
The electrode pin 31 and the heating member 7 can be joined by welding, a conductive adhesive, or brazing. In particular, it is preferable to join the electrode pin 31 and the heating member 7 by electron beam welding or laser beam welding, which has a low connection resistance and hardly generates large heat in the connection process.
If a connection method having a high connection resistance is employed, the connection portion may generate heat when a current is passed through the heating member 7 via the electrode pin 31, and the temperature of the electrostatic chuck portion 20 may not be precisely controlled. Moreover, if a connection method that generates a large amount of heat in the connection process is employed, the adhesive 6 may be deteriorated due to an excessive temperature rise. Therefore, it is preferable to employ electron beam welding or laser beam welding that can eliminate these concerns. In addition, when joining the electrode pin 31 and the heating member 7 by welding, the strength of the welding can be increased by making the material of the electrode pin 31 the same material as the material of the heating member 7 and another material. It can be increased, and is more preferable.

As shown in FIG. 1A, the electrode pin 41 of the second power feeding structure 40 includes a flange 41b provided on the tip surface 41a side (+ Z side) connected to the internal electrode terminal 24, and the flange 41b. And a cylindrical portion 41c erected from the portion 41b. As the electrode pin 41, the same material as that of the electrode pin 31 of the first power supply structure 30 can be used, and the same material as that of the internal electrode terminal 24 may be used.
The connection between the electrode pin 41 and the internal electrode terminal 24 can be joined by welding, conductive adhesive or brazing. The electrode pin 41 and the internal electrode terminal 24 are for applying a voltage to the internal electrode 23 for electrostatic attraction, and a large current does not flow. Therefore, as a method for connecting the electrode pin 41 and the internal electrode terminal 24, the connection can be adopted by a conductive adhesive which is a connection method having a relatively large electric resistance. Thereby, connection work can be simplified.

<Connection line>
As shown in FIG. 1B, the connection line 33 is provided to electrically connect the electrode pin 31 and the connection terminal 32.
As the connection line 33, it is preferable to use an electric cable having flexibility. For example, a spring material or the like can be used in addition to a copper wire, a silver wire, and a twisted wire thereof. Further, it is preferable that the connection line 33 is accommodated in a space between the electrode pin 31 and the connection terminal 32 in a bent state.
When a flexible electric cable is used as the connection line 33 and stored in a bent state, the cooling base 50 is thermally expanded and contracted, and the distance between the electrode pin 31 and the connection terminal 32 changes. Even so, this change in distance can be absorbed. Therefore, it is possible to prevent the electrode pin 31, the connection terminal 32, and these connection portions from being added. Further, when stress or impact is applied to the connection terminal 32, it is possible to prevent the stress or impact from being transmitted to the electrode pin 31, and to prevent the electrode pin 31 and its connecting portion from being damaged.

<Connection terminal>
The connection terminal 32 is a female connector. A male connector (not shown) for supplying electricity to the electrostatic chuck device 100 from an external power source can be connected to the connection terminal 32.
The material of the connection terminal 32 is not limited as long as it is conductive.
The connection terminal 32 is connected to the electrode pin 31 by a connection line 33. Since the connection terminal 32 is connected to the electrode pin 31 via the connection line 33, the electrode pin 31 is hardly affected even when heat or a machine adaptive force is applied to the connection terminal 32. Therefore, methods such as soldering, welding, and caulking can be employed for connection between the connection terminal 32 and the electrode pin 31.
Further, the connection terminal 32 is fixed to the through hole 51 of the cooling base portion 50 via the fixing plate 16.

  The fixing plate 16 is attached to the opening on the −Z side of the through hole 51. The connection terminal 32 and the fixing plate 16 can be fixed, and the fixing plate 16 and the cooling base portion 50 can be fixed by, for example, screwing. Further, the fixing plate 16 may be structured to be fixed to the insulating tube 15. Ceramics, insulating resin, or the like is appropriately selected as the material for the fixing plate 16.

<Shielding tube>
The shielding tube 37 is disposed so as to enclose the electrode pin 31 and surround the outer periphery thereof. A stress relaxation layer 34 is formed between the inner periphery of the shielding tube 37 and the electrode pin 31. The resin layer 80 enters the outer periphery of the shielding tube 37 so as to go around. That is, the shielding tube 37 is disposed between the stress relaxation layer 34 and the resin layer 80.
The shielding tube 37 prevents the uncured resin layer 80 from entering the lower end portion 34 a side (−Z side) of the stress relaxation layer 34 in the bonding step of bonding the cooling base unit 50 and the electrostatic chuck unit 20. .

An upper end portion 37 a on the electrostatic chuck portion 20 side (+ Z side) of the shielding tube 37 is in contact with the heating member 7. The lower end portion 37 b of the shielding tube 37 on the side opposite to the electrostatic chuck portion 20 (−Z side) extends to a position reaching the outer periphery of the connection terminal 32.
The length of the shielding tube 37 may be any length that can prevent the resin layer 80 before curing from entering the lower end portion 34 a side of the stress relaxation layer 34 over the shielding tube 37. Therefore, the lower end portion 37 b of the shielding tube 37 may not reach the outer periphery of the connection terminal 32.

  It is preferable that the upper end portion 37a of the shielding tube 37 contacts the heating member 7 but is not fixed. Further, a gap is formed between the shielding tube 37 and the outer periphery of the connection terminal 32 in the vicinity of the lower end portion 37b. As described above, when the shielding tube 37 is not fixed, the shielding tube 37 follows the resin layer 80 when the resin layer 80 and the cooling base 50 are displaced due to thermal expansion and contraction. And can move.

The shield tube 37 and the electrode pin 31 are not in contact. That is, the shielding tube 37 is disposed so as to provide a predetermined gap between the inner peripheral surface 37 c and the outer peripheral surface 31 e of the flange portion 31 b of the electrode pin 31. By providing the gap, it is possible to prevent the shielding tube 37 from following the positional shift of the resin layer 80 due to thermal expansion and thermal contraction and applying stress to the electrode pin 31.
The amount of displacement of the resin layer 80 varies depending on the material of the resin layer 80, the assumed temperature, the size of the cooling base portion 50, and the like. Therefore, the size of the gap between the inner peripheral surface 37c of the shielding tube 37 and the outer peripheral surface 31e of the collar portion 31b is preferably set according to the amount of displacement of the resin layer 80 with respect to the cooling base portion 50. As an example, it can be about 1 mm.

  For example, a gap of 1 mm or more and 5 mm or less is provided between the outer peripheral surface 37d of the shielding tube 37 and the inner peripheral surface 15a of the insulating tube 15, and the resin layer 80 wraps around the gap to form the outer peripheral resin layer 81. Is done. By providing a gap of 1 mm or more and 5 mm or less, the material constituting the resin layer 80 can uniformly flow into the gap, and the uniform outer peripheral resin layer 81 can be formed.

The material of the shielding tube 37 can be selected from metals, resins, and the like, but is preferably an insulating material, and according to this, the insulating properties of the electrode pins 31 can be enhanced. For example, a silicone or Teflon (registered trademark) resin can be used.
The thickness of the shielding tube 37 is preferably 50 μm or more and 1 mm or less. According to this, it can be set as the shielding tube 37 which has sufficient insulation performance and intensity | strength.

<Stress relaxation layer>
The stress relaxation layer 34 is disposed between the outer periphery of the electrode pin 31 and the inner peripheral surface 37 c of the shielding tube 37.
The stress relaxation layer 34 is provided in order to relieve stress generated when a difference in thermal expansion occurs between the resin layer 80 and the electrostatic chuck portion 20 (particularly the support plate 22). The resin layer 80 and the electrostatic chuck portion 20 have different coefficients of thermal expansion. Accordingly, the resin layer 80 is displaced relative to the electrostatic chuck portion 20 due to the temperature change. Since the electrode pin 31 is connected to the heating member 7 fixed to the electrostatic chuck portion 20 via the adhesive 6 by a connection method such as welding, the electrode pin 31 cannot follow the positional deviation of the resin layer 80. Since the stress relaxation layer 34 is provided on the outer periphery of the electrode pin 31, the stress applied to the electrode pin 31 can be reduced even when the resin layer 80 is displaced. As a result, damage to the electrode pins 31 themselves and damage to the connecting portions between the electrode pins 31 and the heating member 7 can be prevented, and the reliability of the electrostatic chuck device 100 can be improved.

  Further, by providing the stress relaxation layer 34, it is possible to improve the thermal uniformity around the electrode pin 31. A peripheral resin layer 81 is formed around the stress relaxation layer 34 via a shielding tube 37. The outer peripheral resin layer 81 extends from the resin layer 80 into the gap between the shielding tube 37 and the insulating tube 15. Since the outer peripheral resin layer 81 is made of the same resin material as the resin layer 80, it has high thermal conductivity. Therefore, the stress relaxation layer 34 can efficiently transmit heat to the outer peripheral resin layer 81 through the shielding tube 37, and the heat distribution between the electrode pin 31 and the resin layer 80 can be made uniform.

  It is preferable that a gap 9 is formed between the stress relaxation layer 34 and the connection terminal 32 on the lower end 34 a side (−Z side) of the stress relaxation layer 34. The void 9 functions as a region into which the material that is formed when the stress relaxation layer 34 is deformed. Such a void 9 may not be provided when the stress relaxation layer 34 is a material that can be deformed by changing the volume of a foamable material or the like.

  The outer diameter of the stress relaxation layer 34 (that is, the inner diameter of the shielding tube 37 in the present embodiment) is preferably smaller than the width of the heating member 7 to which the electrode pin 31 is connected. Thereby, the stress relaxation layer 34 is included in the width direction of the heating member 7, and it is possible to suppress the difference in thermal conductivity between the stress relaxation layer 34 and the resin layer 80 from inhibiting the thermal uniformity.

  The stress relaxation layer 34 can be bonded to the electrode pin 31 and the shielding tube 37 by being made of an adhesive material. Further, the stress relaxation layer 34 and the electrode pin 31 may be bonded and fixed via an adhesive. By bonding and fixing the stress relaxation layer 34 and the electrode pin 31, it is possible to prevent the stress relaxation layer 34 from being displaced from the electrode pin 31 during manufacturing.

As the stress relaxation layer 34, it is preferable to use a flexible resin material. Specifically, the Young's modulus of the stress relaxation layer 34 is preferably 1 MPa or less, and more preferably 0.3 MPa or less. For example, in addition to a material having a low Young's modulus, such as a flexible silicone resin, a material that can relieve stress by pores, such as foamable polyimide, can be used. Silicone rubber may be used as the stress relaxation layer 34.
The stress relaxation layer 34 may be selected from materials that are inferior in thermal conductivity, withstand voltage, strength, and the like as compared with the material used for the resin layer 80.

  The stress relaxation layer 34 is formed of a material that is more flexible than the outer peripheral resin layer 81. More specifically, the Young's modulus of the stress relaxation layer 34 is lower than the Young's modulus of the outer peripheral resin layer 81. Thereby, the stress relaxation layer 34 can relieve the elastic deformation force generated by the deformation of the outer peripheral resin layer 81 and reduce the load applied to the electrode pin 31.

The stress relaxation layer 44 of the second power feeding structure unit 40 shown in FIG. 1A also has the same structure as the first power feeding structure unit 30. That is, the stress relaxation layer 44 is disposed between the outer periphery of the electrode pin 41 and the inner peripheral surface of the shielding tube 47. Since the electrode pin 41 is connected to the internal electrode terminal 24, it cannot follow the displacement of the resin layer 80 with respect to the electrostatic chuck portion 20. By providing the stress relaxation layer 44, even when the resin layer 80 and the electrostatic chuck portion 20 are displaced, the stress applied to the electrode pin 41 can be reduced, and the electrode pin 41 itself is damaged. In addition, it is possible to prevent the connection portion between the electrode pin 41 and the internal electrode terminal 24 from being damaged. Further, the stress relaxation layer 44 is formed of a material that is more flexible than the outer peripheral resin layer 81, similarly to the stress relaxation layer 34. Thereby, the stress relaxation layer 44 can relieve the elastic deformation force generated by the deformation of the outer peripheral resin layer 81.
Further, since the stress relaxation layer 44 is provided, there is an effect of improving the thermal uniformity around the electrode pin 41.

<Resin layer 80>
As shown in FIG. 1A, the resin layer 80 is interposed between the second surface 20 b of the electrostatic chuck portion 20 and the first surface 50 a of the cooling base portion 50. The resin layer 80 bonds and integrates the electrostatic chuck portion 20 to which the heating member 7 is bonded and the cooling base portion 50, and has a thermal stress relieving action.
The resin layer 80 has voids in the interior, the second surface 20b of the electrostatic chuck portion 20, the lower surface (the surface on the −Z side) of the heating member 7, and the interface with the first surface 50a of the cooling base portion 50. It is desirable that there are few defects. If voids or defects are formed, the heat transfer property may be reduced, and the soaking property of the plate sample W may be hindered.

  The resin layer 80 is formed of, for example, a cured body obtained by heat-curing a silicone resin composition or an acrylic resin. The resin layer 80 is preferably formed by filling a fluid resin composition between the electrostatic chuck portion 20 and the cooling base portion, followed by heat curing. The heating member 7 is provided on the first surface 50a of the cooling base 50, thereby forming irregularities. Further, the first surface 50a of the cooling base unit 50 and the second surface 20b of the electrostatic chuck unit 20 are not necessarily flat. A fluid resin composition is filled between the cooling base portion 50 and the electrostatic chuck portion 20 and then cured to form the resin layer 80, thereby causing unevenness between the electrostatic chuck portion 20 and the cooling base portion 50. Thus, the generation of voids in the resin layer 80 can be suppressed. Thereby, the heat conduction characteristic of the resin layer 80 can be made uniform in the surface, and the thermal uniformity of the electrostatic chuck portion 20 can be improved.

  The silicone-based resin composition is a resin excellent in heat resistance and elasticity, and includes a silicon compound having a siloxane bond (Si—O—Si). This silicone resin composition can be represented, for example, by the chemical formula of the following formula (1) or formula (2).

但し、Ｒは、Ｈまたはアルキル基（Ｃ_ｎＨ_２ｎ＋１−：ｎは整数）である。

Here, R is, H or an alkyl group _{(C n H 2n + 1 -} : n is an integer) is.

但し、Ｒは、Ｈまたはアルキル基（Ｃ_ｎＨ_２ｎ＋１−：ｎは整数）である。

Here, R is, H or an alkyl group _{(C n H 2n + 1 -} : n is an integer) is.

As such a silicone resin, a silicone resin having a thermosetting temperature of 70 ° C. or higher and 140 ° C. or lower is particularly preferable.
Here, when the thermosetting temperature is lower than 70 ° C., when the support plate 22 of the electrostatic chuck unit 20 and the cooling base unit 50 are bonded in a state of being opposed to each other, curing starts in the bonding process. It is not preferable because it is inferior in properties. On the other hand, when the thermosetting temperature exceeds 140 ° C., the difference in thermal expansion between the support plate 22 of the electrostatic chuck unit 20 and the cooling base unit 50 is large, and the support plate 22 of the electrostatic chuck unit 20 and the cooling base unit 50 are large. The stress between the two increases, and there is a possibility that peeling occurs between them.

  The silicone resin is preferably a resin having a Young's modulus after curing of 8 MPa or less. Here, when the Young's modulus after curing exceeds 8 MPa, the thermal expansion difference between the support plate 22 and the cooling base portion 50 can be absorbed when the resin layer 80 is subjected to a heat cycle of increasing and decreasing temperatures. This is not preferable because the durability of the resin layer 80 is lowered.

The resin layer 80 includes a filler made of an inorganic oxide, inorganic nitride, or inorganic oxynitride having an average particle diameter of 1 μm or more and 10 μm or less, for example, silicon oxide (SiO ₂ ) on the surface of aluminum nitride (AlN) particles. It is preferable that the surface covering aluminum nitride (AlN) particle | grains in which the coating layer which consists of was formed contain.
The surface-coated aluminum nitride (AlN) particles are mixed to improve the thermal conductivity of the silicone resin, and the heat transfer rate of the resin layer 80 can be controlled by adjusting the mixing rate. .

That is, by increasing the mixing rate of the surface-coated aluminum nitride (AlN) particles, the heat transfer rate of the organic adhesive constituting the resin layer 80 can be increased.
In addition, since a coating layer made of silicon oxide (SiO ₂ ) is formed on the surface of aluminum nitride (AlN) particles, it has superior water resistance compared to simple aluminum nitride (AlN) particles that are not surface-coated. have. Therefore, the durability of the resin layer 80 containing the silicone resin composition as a main component can be secured, and as a result, the durability of the electrostatic chuck device 100 can be dramatically improved.

Further, since the surface-coated aluminum nitride (AlN) particles are coated with a coating layer made of silicon oxide (SiO ₂ ) having excellent water resistance, the surface of the aluminum nitride (AlN) particles is aluminum nitride (AlN). ) Is not hydrolyzed by water in the atmosphere, the heat transfer rate of aluminum nitride (AlN) is not lowered, and the durability of the resin layer 80 is improved.
The surface-coated aluminum nitride (AlN) particles do not have a risk of becoming a contamination source for the plate-like sample W such as a semiconductor wafer, and can be said to be a preferable filler from this point.

  Since the surface-coated aluminum nitride (AlN) particles can obtain a strong bonding state with Si in the coating layer and the silicone-based resin composition, the stretchability of the resin layer 80 can be improved. is there. Thereby, the thermal stress resulting from the difference between the thermal expansion coefficient of the support plate 22 of the electrostatic chuck part 20 and the thermal expansion coefficient of the cooling base part 50 can be relieved, and the electrostatic chuck part 20 and the cooling base part 50 can be relaxed. Can be adhered with high precision and strength. In addition, since the durability against the heat cycle load during use is sufficient, the durability of the electrostatic chuck device 100 is improved.

The average particle diameter of the surface-coated aluminum nitride (AlN) particles is preferably 1 μm or more and 10 μm or less, more preferably 2 μm or more and 5 μm or less.
Here, when the average particle size of the surface-coated aluminum nitride (AlN) particles is less than 1 μm, the contact between the particles becomes insufficient, and as a result, the heat transfer rate may be lowered, and the particle size is small. If it is too much, workability such as handling is reduced, which is not preferable. On the other hand, if the average particle diameter exceeds 10 μm, the thickness of the adhesive layer tends to vary, which is not preferable.

  Further, the resin layer 80 may be formed of a thermosetting acrylic resin adhesive having a Young's modulus of 1 GPa or less and flexibility (Shore hardness of A100 or less). In this case, the filler may or may not be contained.

<Outer peripheral resin layer>
As shown in FIG. 1B, the resin layer 80 wraps between the outer peripheral surface 37 d of the shielding tube 37 and the inner peripheral surface 15 a of the insulating tube 15 to form an outer peripheral resin layer 81.
The outer peripheral resin layer 81 is made of the same resin material as that of the resin layer 80, and the thermal conductivity is increased by containing, for example, the filler described above. On the other hand, the resin material constituting the stress relaxation layer 34 does not contain a filler or maintains a small amount even if it is contained in order to maintain flexibility. In this case, the thermal conductivity of the stress relaxation layer 34 is lower than that of the resin layer 80. Further, when a foaming material is used as the resin material constituting the stress relaxation layer 34, the thermal conductivity becomes very small. Since the thermal conductivity of the stress relaxation layer 34 is low, there is a possibility that the thermal uniformity of the electrostatic chuck portion 20 may be hindered around the stress relaxation layer 34.
In the electrostatic chuck device 100 of the present embodiment, the stress relaxation layer 34 can transmit heat to the outer peripheral resin layer 81 through the shielding tube 37 by forming the outer peripheral resin layer 81. Thereby, the thermal uniformity around the electrode pin 31 can be improved.

  The outer peripheral resin layer 81 is in contact with the inner peripheral surface 15 a of the insulating tube 15 embedded in the through hole 51 of the cooling base portion 50. The outer peripheral resin layer 81 is formed so as to spread on the inner peripheral surface 15a of the insulating tube 15, so that heat exchange with the cooling base 50 is performed with high efficiency. Therefore, the stress relaxation layer 34 is efficiently cooled via the outer peripheral resin layer 81, and the thermal uniformity of the electrostatic chuck portion 20 can be improved.

The outer peripheral resin layer 81 is preferably formed by the resin layer 80 wrapping between the shielding tube 37 and the insulating tube 15 and being a layer continuous with the resin layer 80.
For example, when a different kind of material from the resin layer 80 is used as the outer resin layer 81, or when a resin is separately injected after forming the resin layer 80, the resin is contained in the outer resin layer 81. Thus, the outer peripheral resin layer 81 cannot function as an insulating layer.
By making the outer peripheral resin layer 81 continuous with the resin layer 80, the outer peripheral resin layer 81 functions as an insulating layer and suitably prevents dielectric breakdown between the first power supply structure 30 and the cooling base 5. I can do it.

<Manufacturing method>
Next, a method for manufacturing the electrostatic chuck device 100 will be described.
First, the plate-shaped mounting plate 21 and the support plate 22 are produced from an aluminum oxide-silicon carbide (Al ₂ O ₃ —SiC) composite sintered body or an yttrium oxide (Y ₂ O ₃ ) sintered body. In this case, a mixed powder containing silicon carbide powder and aluminum oxide powder or yttrium oxide powder is formed into a desired shape, and then, for example, at a temperature of 1400 ° C. to 2000 ° C. in a non-oxidizing atmosphere, preferably an inert atmosphere. The mounting plate 21 and the support plate 22 can be obtained by baking for a predetermined time.

Next, a plurality of fixing holes for fitting and holding the internal electrode terminals 24 are formed in the support plate 22.
Next, the internal electrode terminal 24 is fabricated so as to have a size and shape that can be tightly fixed to the fixing hole of the support plate 22. As a method for producing the internal electrode terminal 24, for example, when the internal electrode terminal 24 is made of a conductive composite sintered body, a method in which a conductive ceramic powder is molded into a desired shape and subjected to pressure firing is exemplified. .

At this time, the conductive ceramic powder used for the internal electrode terminal 24 is preferably a conductive ceramic powder made of the same material as the internal electrode 23 for electrostatic adsorption.
In addition, when the internal electrode terminal 24 is made of metal, a method of using a refractory metal and forming by a metal processing method such as a grinding method or a powder metallurgy may be used.

Next, for electrostatic adsorption, a conductive material such as the conductive ceramic powder is dispersed in an organic solvent so as to come into contact with the internal electrode terminal 24 in a predetermined region on the surface of the support plate 22 in which the internal electrode terminal 24 is fitted. An internal electrode forming coating solution is applied and dried to form an electrostatic adsorption internal electrode 23.
As this coating method, it is desirable to use a screen printing method or the like because it is necessary to apply the film to a uniform thickness. Other methods include forming a thin film of the above-mentioned refractory metal by vapor deposition or sputtering, or arranging an electroconductive ceramic or refractory metal thin plate to provide an internal electrode for electrostatic adsorption. 23 and the like.

  Further, in order to improve insulation, corrosion resistance, and plasma resistance in a region other than the region where the electrostatic adsorption internal electrode 23 is formed on the support plate 22, the same composition as the mounting plate 21 and the support plate 22 is used. Alternatively, an insulating material layer including a powder material having the same main component is formed. For example, the insulating material layer is formed by applying a coating liquid in which an insulating material powder having the same composition or the same main component as the mounting plate 21 and the supporting plate 22 is dispersed in an organic solvent by screen printing or the like, and drying. Can be formed.

Next, the mounting plate 21 is superposed on the electrostatic adsorption internal electrode 23 and the insulating material layer on the support plate 22, and then these are integrated by hot pressing under high temperature and high pressure. The atmosphere in this hot press is preferably a vacuum or an inert atmosphere such as Ar, He, N ₂ or the like. Moreover, the pressure at the time of uniaxial pressurization in a hot press is preferably 5 MPa to 10 MPa, and the temperature is preferably 1400 ° C. to 1850 ° C.

By this hot pressing, the electrostatic adsorption internal electrode 23 is fired to become the electrostatic adsorption internal electrode 23 made of a conductive composite sintered body. At the same time, the support plate 22 and the mounting plate 21 are joined and integrated.
The internal electrode terminal 24 is refired by hot pressing under high temperature and high pressure, and is closely fixed to the fixing hole of the support plate 22.
Then, the upper and lower surfaces, outer periphery, gas holes, and the like of these joined bodies are machined to form the electrostatic chuck portion 20.

Next, in a predetermined region of the second surface 20 b of the electrostatic chuck portion 20, a sheet shape having heat resistance and insulation properties such as polyimide resin, silicone resin, epoxy resin, etc. and the same pattern shape as the heating member 7. Alternatively, a film-like adhesive resin is attached to form an adhesive material 6.
This adhesive 6 is adhered to the second surface 20b of the electrostatic chuck portion 20 with an adhesive resin sheet or adhesive resin film having heat resistance and insulation properties such as polyimide resin, silicone resin, and epoxy resin, It can also be produced by forming the same pattern as the heating member 7 on this sheet or film.

Next, the adhesive 6 has a constant thickness of 0.2 mm or less, preferably 0.1 mm or less, such as a titanium (Ti) thin plate, a tungsten (W) thin plate, a molybdenum (Mo) thin plate, or the like. A nonmagnetic metal thin plate is attached, and this nonmagnetic metal thin plate is etched into a desired heater pattern by a photolithography method to obtain a heating member 7.
Thereby, the electrostatic chuck part 20 with the heating member 7 in which the heating member 7 having a desired heater pattern is formed on the second surface 20b of the electrostatic chuck part 20 via the adhesive 6 is obtained.

Next, electrode pins 31 and 41 having a predetermined size and shape are produced. The manufacturing method of the electrode pins 31 and 41 is the same as the manufacturing method of the internal electrode terminal 24 described above. For example, when the electrode pins 31 and 41 are conductive composite sintered bodies, the conductive ceramic powder is formed in a desired shape. The method etc. which are shape | molded and pressure-baked are mentioned.
Moreover, when the electrode pins 31 and 41 are made of metal, a method of using a refractory metal and a metal working method such as a grinding method or powder metallurgy, or the like can be used.

  Next, the electrode pin 31, the connection line 33, and the connection terminal 32 that configure the first power feeding structure 30 are connected to each other. Similarly, the electrode pin 41, the connection line 43, and the connection terminal 42 which comprise the 2nd electric power feeding structure part 40 are connected, respectively. The connection between the electrode pins 31 and 41 and the connection lines 33 and 43 can be performed by welding or soldering. Further, the connection between the connection lines 33 and 43 and the connection terminals 32 and 42 can be performed by caulking.

Next, the electrode pin 31 is connected to the heating member 7 by electron beam welding. Further, the electrode pin 41 is connected to the internal electrode terminal 24 by a conductive adhesive.
Through the above steps, the electrostatic chuck unit 20 is electrically connected to the connection terminals 32 and 42 via the electrode pins 31 and 41 and the connection wires 33 and 43.

Next, a flexible resin is adhered to the outer periphery of the electrode pins 31 and 41 to form the stress relaxation layers 34 and 44. Further, shielding tubes 37 and 47 are arranged on the outer periphery of the stress relaxation layers 34 and 44.
In the step of forming the stress relaxation layers 34 and 44, after the shielding tubes 37 and 47 are disposed around the electrode pins 31 and 41 in advance, the uncured stress relaxation layers 34 and 44 are poured into the shielding tubes 37 and 47. You may carry out by making it harden | cure.

On the other hand, a metal material made of aluminum (Al), aluminum alloy, copper (Cu), copper alloy, stainless steel (SUS), etc. is machined, and a coolant is circulated inside the metal material as necessary. Form roads.
It is preferable that at least the surface of the cooling base 50 exposed to plasma is subjected to anodizing or an insulating film such as alumina is formed.
Next, the through holes 51 and 52 are formed. Further, the insulating tube 15 is inserted and fixed in these through holes 51 and 52 with an adhesive (not shown).

Next, a spacer (not shown) is attached near the edge of the first surface 50 a of the cooling base 50.
Next, an adhesive made of, for example, a silicone resin composition is applied to a predetermined region of the first surface 50 a of the cooling base unit 50. This adhesive is an uncured resin constituting the resin layer 80. The application amount of the adhesive is set within a predetermined amount so that the electrostatic chuck unit 20 and the cooling base unit 50 can be joined and integrated in a state where a predetermined interval is maintained by the spacer.
Examples of the method for applying the adhesive include manual application using a spatula and the like, as well as a bar coating method and a screen printing method. However, it is necessary to form the adhesive in a predetermined region on the cooling base 50 with high accuracy. Therefore, it is preferable to use a screen printing method or the like.

After the application, the electrostatic chuck unit 20 and the cooling base unit 50 are superposed through an adhesive and a spacer having a predetermined thickness.
In this superposition process, the electrode pins 31 and 41, the shielding tubes 37 and 47, the connection wires 33 and 43, and the connection terminals 32 and 42 suspended from the electrostatic chuck portion 20 are insulated tubes embedded in the through holes 51 and 52. 15 is inserted inside.
Next, the space between the electrostatic chuck portion 20 and the cooling base portion 50 is dropped until the thickness of the spacer is reached, and after the excess adhesive that has been pushed out is removed, the adhesive is cured to form the resin layer 80.

  As described above, the liquid adhesive is applied to the first surface 50a of the cooling base portion 50, and the electrostatic chuck portion 20 is pressed from above, so that the gap between the outer periphery of the insulating tube 15 and the shielding tubes 37 and 47 is increased. Liquid adhesive wraps around the gap. Furthermore, the outer peripheral resin layer 81 extending from the resin layer 80 can be formed by curing the wrapped adhesive.

Next, the fixing plate 16 is attached to the openings on the −Z side of the through holes 51 and 52. Further, the connection terminals 32 and 42 depending from the electrostatic chuck 20 are fixed to the fixing plate 16.
As described above, the electrostatic chuck portion 20 and the cooling base portion 50 are joined and integrated through the resin layer 80, and the electrostatic chuck device 100 of this embodiment is obtained.

  In the electrostatic chuck device 100 of the first embodiment, stress relaxation layers 34 and 44 are provided on the outer periphery of the electrode pins 31 and 41. As a result, even if the electrostatic chuck portion 20 and the resin layer 80 are displaced due to the difference in thermal expansion coefficient, the stress applied to the electrode pins 31 and 41 can be relaxed. Therefore, it is possible to prevent damage to the electrode pins 31 and 41 and damage to the connection portion between the electrode pins 31 and 41 and the internal electrode terminal 24 or the heating member 7.

  Further, the electrostatic chuck device 100 of the first embodiment has an outer peripheral resin layer 81 in which the resin layer 80 extends between the inner periphery of the insulating tube 15 and the outer periphery of the shielding tubes 37 and 47. The outer peripheral resin layer 81 can play a role of transferring heat from the outer periphery of the stress relaxation layers 34, 44 to the cooling base portion 50 via the shielding tubes 37, 47. Therefore, the stress relaxation layers 34 and 44 are efficiently cooled. Furthermore, the region in contact with the stress relaxation layers 34 and 44 of the electrostatic chuck portion 20 can be efficiently cooled, and the thermal uniformity of the electrostatic chuck portion 20 can be improved.

  Furthermore, in the electrostatic chuck device 100 of the first embodiment, the stress relaxation layers 34 and 44 are formed of a material that is more flexible than the outer peripheral resin layer 81. When the outer peripheral resin layer 81 is deformed due to thermal expansion or the like, the elastic deformation force of the outer peripheral resin layer 81 applies a load to the electrode pins 31 and 41 via the shielding tubes 37 and 47 and the stress relaxation layers 34 and 44. . Since the stress relaxation layers 34 and 44 are more flexible than the outer peripheral resin layer 81, the stress relaxation layers 34 and 44 are flexibly deformed through the elastic deformation force transmission path to relieve the stress. Thereby, the load added to the electrode pins 31 and 41 can be reduced. Thereby, the damage of the electrode pins 31 and 41 itself and the damage of the connection part of the electrode pins 31 and 41 can be prevented.

<< Second Embodiment >>
FIG. 3 is a cross-sectional view showing the electrostatic chuck device 200 of the second embodiment. Hereinafter, the electrostatic chuck device 200 will be described with reference to FIG. In addition, about the component of the same aspect as the above-mentioned 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
The electrostatic chuck device 200 of the second embodiment has a point that the first and second power feeding structures 230 and 240 do not have the shielding tubes 37 and 47 (see FIG. 1A) in the first embodiment. Different.

The electrostatic chuck device 200 includes a disk-shaped electrostatic chuck portion 20 on which a plate-shaped sample W is installed, a disk-shaped cooling base portion 250 that cools the electrostatic chuck portion 20, and these are bonded and integrated. And a resin layer 280 to be used.
The cooling base portion 250 includes first and second through holes 251 and 252 penetrating in the thickness direction. Insulating tubes 15 are embedded in the first and second through holes 251 and 252, respectively. Each insulating tube 15 includes first and second power feeding structures 230 and 240, respectively.
Further, an outer peripheral resin layer 281 extending from the resin layer 280 is formed between the inner peripheral surface of the insulating tube 15 and the first and second power feeding structure portions 230 and 240.

The first power feeding structure unit 230 includes a connection terminal 32, a connection line 33, an electrode pin 31, and a stress relaxation layer 234. The electrode pins 31 of the first power supply structure unit 230 are connected to the terminal unit 8 of the heating member 7.
The stress relaxation layer 234 of the first power supply structure 230 is formed on the outer periphery of the electrode pin 31. Further, an outer peripheral resin layer 281 extending from the resin layer 280 is formed between the outer periphery of the stress relaxation layer 234 and the inner peripheral surface of the insulating tube 15.

Similarly, the second power feeding structure 240 includes a connection terminal 42, a connection line 43, an electrode pin 41, and a stress relaxation layer 244. The electrode pin 41 of the second power feeding structure 240 is connected to the internal electrode terminal 24 exposed from the second surface 20 b of the electrostatic chuck unit 20.
The stress relaxation layer 244 of the second power feeding structure 240 is formed on the outer periphery of the electrode pin 41. Further, an outer peripheral resin layer 281 extending from the resin layer 280 is formed between the outer periphery of the stress relaxation layer 244 and the inner peripheral surface of the insulating tube 15.

  The stress relaxation layers 234 and 244 are provided in order to relieve stress generated when a difference in thermal expansion occurs between the resin layer 280 and the electrostatic chuck portion 20 (particularly the support plate 22). Since the stress relaxation layers 234 and 244 are provided, the resin layer 280 is applied to the electrode pins 31 and 41 even when the resin layer 280 is displaced relative to the electrostatic chuck portion 20 due to a temperature change. Stress can be reduced. As a result, the electrode pins 31 and 41 themselves can be prevented from being damaged and the connecting portions of the electrode pins 31 and 41 can be prevented from being damaged, and the reliability of the electrostatic chuck device 200 can be improved.

  Similarly to the first embodiment, the stress relaxation layers 234 and 244 are formed of a material that is more flexible than the outer peripheral resin layer 281. When the outer peripheral resin layer 281 is deformed due to thermal expansion or the like, the elastic deformation force of the outer peripheral resin layer 281 applies a load to the electrode pins 31 and 41 via the stress relaxation layers 234 and 244. Since the stress relaxation layers 234 and 244 are more flexible than the outer peripheral resin layer 281, the stress can be flexibly deformed in the elastic deformation force transmission path to relieve the stress and reduce the load applied to the electrode pins 31 and 41. . Thereby, the damage of the electrode pins 31 and 41 itself and the damage of the connection part of the electrode pins 31 and 41 can be prevented.

  Outer peripheral resin layers 281 are formed around the stress relaxation layers 234 and 244 and in the gap with the insulating tube 15. Since the outer peripheral resin layer 281 is made of the same resin material as the resin layer 280, it has high thermal conductivity. Therefore, the stress relaxation layers 234 and 244 can efficiently transmit heat to the outer peripheral resin layer 281, and the heat distribution between the electrode pins 31 and 41 and the resin layer 280 can be made uniform. The outer peripheral resin layer 281 can play a role of transferring heat from the outer periphery of the stress relaxation layers 234 and 244 to the cooling base portion 250. Therefore, the stress relaxation layers 234 and 244 are efficiently cooled. Furthermore, the regions of the electrostatic chuck portion 20 that are in contact with the stress relaxation layers 234 and 244 can be efficiently cooled, and the thermal uniformity of the electrostatic chuck portion 20 can be improved.

<< Third Embodiment >>
FIG. 4 is a cross-sectional view showing an electrostatic chuck device 300 according to the third embodiment. Hereinafter, the electrostatic chuck device 300 will be described with reference to FIG. In addition, about the component of the same aspect as the above-mentioned 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
In the electrostatic chuck device 300 of the third embodiment, the first and second power feeding structures 330 and 340 include the shielding tubes 37 and 47 and the stress relaxation layers 34 and 44 in the first embodiment (see FIG. 1A). The difference is that it does not have.

The electrostatic chuck device 300 includes a disk-shaped electrostatic chuck portion 20 on which a plate-shaped sample W is placed, a disk-shaped cooling base portion 350 that cools the electrostatic chuck portion 20, and these are bonded and integrated. And a resin layer 380 to be used.
The cooling base portion 350 includes first and second through holes 351 and 352 that penetrate in the thickness direction. Insulating tubes 15 are embedded in the first and second through holes 351 and 352, respectively. Each insulating tube 15 includes first and second power feeding structures 330 and 340, respectively.
Further, an outer peripheral resin layer 381 extending from the resin layer 380 is formed between the inner peripheral surface of the insulating tube 15 and the first and second power feeding structure portions 330 and 340.

The first power feeding structure 330 has a connection terminal 32, a connection line 33, and an electrode pin 31. The electrode pin 31 of the first power supply structure 330 is connected to the terminal 8 of the heating member 7.
An outer peripheral resin layer 381 is formed on the outer periphery of the electrode pin 31 of the first power feeding structure 330 via a predetermined gap (gap 301).
Similarly, the second power supply structure 340 includes a connection terminal 42, a connection line 43, and an electrode pin 41. The electrode pin 41 of the second power supply structure 340 is connected to the internal electrode terminal 24 exposed from the second surface 20 b of the electrostatic chuck unit 20.
An outer peripheral resin layer 381 is formed on the outer periphery of the electrode pin 41 of the second power feeding structure 340 via a predetermined gap (gap 401).

  Since the gaps 301 and 401 are provided on the outer circumferences of the electrode pins 31 and 41, even if the resin layer 380 is displaced relative to the electrostatic chuck portion 20 due to a temperature change, the electrodes No stress is applied to the pins 31 and 41. As a result, the electrode pins 31 and 41 themselves can be prevented from being damaged and the connecting portions of the electrode pins 31 and 41 can be prevented from being damaged, and the reliability of the electrostatic chuck device 300 can be improved.

  In the electrostatic chuck device 300 of the present embodiment, the outer peripheral resin layer 381 is formed around the electrode pins 31 and 41 via the gaps 301 and 401. The outer peripheral resin layer 381 is in contact with the inner peripheral surface of the insulating tube 15 embedded in the first and second through holes 351 and 352 of the cooling base portion 350, respectively. The outer peripheral resin layer 381 is formed so as to spread over the inner peripheral surface of the insulating tube 15, so that heat exchange with the cooling base portion 350 is performed with high efficiency. Therefore, the cooling efficiency of the resin layer 380 around the gaps 301 and 401 is enhanced as compared with other portions. Therefore, even in the vicinity of the gaps 301 and 401 in the electrostatic chuck portion 20, the cooling can be performed in the same manner as the other portions, and the thermal uniformity of the electrostatic chuck portion 20 can be ensured.

  The gaps 301 and 401 are obtained by assembling the electrostatic chuck device 300 with a temporary resin layer (hereinafter referred to as temporary resin layer) provided around the electrode pins 31 and 41 and removing the temporary resin layer as a final process. It is preferable to form by. As a method of removing the temporary resin layer, a method of dissolving using heat or an organic solvent can be used. In this case, it is preferable to use a material that dissolves with heat or an organic solvent as a constituent material of the temporary resin layer. By adopting the method of removing the temporary resin layer, the gaps 301 and 401 can be formed without machining, and there is no possibility of damaging surrounding members. In addition, cleaning after the formation of the gaps 301 and 401 is easier than when machining.

  Although various embodiments of the present invention have been described above, each configuration in each embodiment and combinations thereof are examples, and addition, omission, replacement, and configuration of configurations are within the scope not departing from the spirit of the present invention. And other changes are possible. Further, the present invention is not limited by the embodiment.

6 ... Adhesive, 7 ... Heating member (heater element), 9, 301, 401 ... Air gap (gap), 15 ... Insulating tube (insulator), 16 ... Fixed plate, 20 ... Electrostatic chuck, 20a ... First Surface, 20b ... second surface, 23 ... internal electrode for electrostatic attraction, 24 ... internal electrode terminal, 30, 40, 230, 240, 330, 440 ... feeding structure, 31,41 ... electrode pin, 32,42 Connection terminal 33, 43 Connection line 34, 44, 234, 244 Stress relaxation layer 37, 47 Shield tube 40 Second feeding structure 50, 250, 350 Cooling base 51 , 52, 251, 252, 351, 352 ... through-hole, 80, 280, 380 ... resin layer, 81,281,381 ... peripheral resin layer, 100, 200,300 ... electrostatic chuck device, W ... plate-like sample

Claims (8)

An electrostatic chuck portion having a first surface on which a plate-like sample is placed and a second surface opposite to the first surface, and including an internal electrode for electrostatic adsorption;
A cooling base portion disposed on the second surface side for cooling the electrostatic chuck portion;
A resin layer interposed between and adhering between the electrostatic chuck portion and the cooling base portion;
A heating member fixed to the second surface of the electrostatic chuck portion;
An electrode pin inserted through a through hole penetrating the cooling base portion in the thickness direction and having a tip connected to the heating member;
A stress relaxation layer provided on the outer periphery of the electrode pin;
An electrostatic chuck device having an outer peripheral resin layer extending from the resin layer between an inner periphery of the through hole and an outer periphery of the stress relaxation layer. An electrostatic chuck portion having a first surface on which a plate-like sample is placed and a second surface opposite to the first surface, and including an internal electrode for electrostatic adsorption;
A cooling base portion disposed on the second surface side for cooling the electrostatic chuck portion;
A resin layer interposed between and adhering between the electrostatic chuck portion and the cooling base portion;
An internal electrode terminal connected to the electrostatic chuck internal electrode and exposed from the second surface of the electrostatic chuck portion;
An electrode pin inserted through a through hole penetrating the cooling base portion in the thickness direction and having a tip connected to the internal electrode terminal;
A stress relaxation layer provided on the outer periphery of the electrode pin;
An electrostatic chuck device having an outer peripheral resin layer extending from the resin layer between an inner periphery of the through hole and an outer periphery of the stress relaxation layer.   The electrostatic chuck device according to claim 1, wherein the stress relaxation layer is formed of a material that is more flexible than the outer peripheral resin layer.   The electrostatic chuck apparatus according to claim 1, wherein the stress relaxation layer has a Young's modulus of 1 MPa or less.   5. The electrostatic chuck device according to claim 1, further comprising an insulating shielding tube disposed between the stress relaxation layer and the outer peripheral resin layer so as to surround the electrode pin. 6. An electrostatic chuck portion having a first surface on which a plate-like sample is placed and a second surface opposite to the first surface, and including an internal electrode for electrostatic adsorption;
A cooling base portion disposed on the second surface side for cooling the electrostatic chuck portion;
A resin layer interposed between and adhering between the electrostatic chuck portion and the cooling base portion;
A heating member fixed to the second surface of the electrostatic chuck portion;
An electrode pin inserted through a through hole penetrating the cooling base portion in the thickness direction and having a tip connected to the heating member;
An electrostatic chuck device having an outer peripheral resin layer extending from the resin layer to the inner periphery of the through hole and formed on the outer periphery of the electrode pin via a gap. An electrostatic chuck portion having a first surface on which a plate-like sample is placed and a second surface opposite to the first surface, and including an internal electrode for electrostatic adsorption;
A cooling base portion disposed on the second surface side for cooling the electrostatic chuck portion;
A resin layer interposed between and adhering between the electrostatic chuck portion and the cooling base portion;
An internal electrode terminal connected to the electrostatic chuck internal electrode and exposed from the second surface of the electrostatic chuck portion;
An electrode pin inserted through a through hole penetrating the cooling base portion in the thickness direction and having a tip connected to the internal electrode terminal;
An electrostatic chuck device having an outer peripheral resin layer extending from the resin layer to the inner periphery of the through hole and formed on the outer periphery of the electrode pin via a gap.   The electrostatic chuck apparatus according to claim 6, further comprising an insulating shielding tube that is fixed to an inner periphery of the outer peripheral resin layer and is disposed so as to surround the electrode pin.

Images