WO2016114399A1 - Electrostatic chuck - Google Patents

Abstract

Provided is an electrostatic chuck having a first main surface on which an object to be processed is mounted, and a second main surface opposite to the first main surface, the electrostatic chuck being characterized by being provided with: a ceramic dielectric substrate; a base plate which is disposed apart from the ceramic dielectric substrate and supports the ceramic dielectric substrate; and a heater plate disposed between the ceramic dielectric substrate and the base plate, wherein the heater plate has: a first support plate including a metal; a second support plate including a metal; a heater element which is disposed between the first support plate and the second support plate and generates heat by electric current flow; a first resin layer disposed between the first support plate and the heater element; and a second resin layer disposed between the second support plate and the heater element.

Description

Electrostatic chuck

An aspect of the present invention generally relates to an electrostatic chuck.

In a plasma processing chamber that performs etching, CVD (Chemical Vapor Deposition), sputtering, ion implantation, ashing, and the like, an electrostatic chuck is used as means for adsorbing and holding a processing object such as a semiconductor wafer or a glass substrate. The electrostatic chuck applies electrostatic attraction power to a built-in electrode and attracts a substrate such as a silicon wafer by electrostatic force.

In such a substrate processing apparatus having an electrostatic chuck, temperature control of the wafer is required in order to improve yield and quality. Two types of performance are required for temperature control of the wafer. One performance is temperature uniformity that makes the temperature distribution in the plane of the wafer uniform. Another performance is temperature controllability that intentionally makes a difference in the in-plane temperature of the wafer. In controlling the temperature of the wafer, the performance of the heater built in the electrostatic chuck is one of the important factors. In general, temperature uniformity is in a trade-off relationship with temperature controllability.

In the substrate processing apparatus, higher throughput is further demanded. In order to achieve high throughput of the substrate processing apparatus, it is preferable that the heat capacity of the heater built in the electrostatic chuck is relatively small.

In the wafer processing process, an RF (Radio Frequency) voltage (high frequency voltage) is applied. When an RF voltage is applied, a general heater generates heat under the influence of a high frequency. Then, the temperature controllability decreases. Moreover, when the RF voltage is applied, a leakage current flows to the equipment side. Therefore, a mechanism such as a filter is required on the equipment side.
When the heater is built in the electrostatic chuck, the reliability of the heater built-in method (for example, bonding method) is one of the important factors.

In a process in a plasma etching apparatus or the like, plasmas with various intensities and various distributions are irradiated onto the wafer. When the wafer is irradiated with plasma, it is required to control the temperature of the wafer to a temperature suitable for the process. In addition, when the wafer is irradiated with plasma, temperature uniformity and temperature controllability are required. Furthermore, in order to improve productivity, it is required to reach the wafer temperature to a predetermined temperature in a relatively short time. Even when there is a rapid temperature change, heat supply, or application of a high-frequency voltage, high reliability is required for the electrostatic chuck and the wafer. It is difficult to satisfy such requirements at the same time.

JP 2010-40644 A

The present invention has been made based on recognition of such problems, and an object thereof is to provide an electrostatic chuck that can satisfy temperature uniformity and temperature controllability.

According to one aspect of the present invention, a ceramic dielectric substrate having the first main surface on which the processing object is placed and the second main surface opposite to the first main surface, and the ceramic A base plate provided at a position away from the dielectric substrate and supporting the ceramic dielectric substrate; and a heater plate provided between the ceramic dielectric substrate and the base plate, wherein the heater plate is a metal A first support plate containing metal, a second support plate containing metal, a heater element that is provided between the first support plate and the second support plate and generates heat when an electric current flows, A first resin layer provided between the first support plate and the heater element; and a second resin layer provided between the second support plate and the heater element. Electrostatic chatter There is provided.

It is a typical perspective view showing the electrostatic chuck concerning this embodiment. It is a typical sectional view showing the electrostatic chuck concerning this embodiment. It is a typical perspective view showing the heater plate of this embodiment. It is a typical perspective view showing the heater plate of this embodiment. It is a typical exploded view showing the heater plate of this embodiment. It is a typical exploded view showing the modification of the heater plate of this embodiment. It is typical sectional drawing which illustrates an example of the manufacturing method of this embodiment. It is typical sectional drawing which illustrates another example of the manufacturing method of this embodiment. It is a typical exploded view showing the electrostatic chuck concerning this embodiment. It is an electric circuit diagram showing the electrostatic chuck concerning this embodiment. It is a typical top view which illustrates the example of the heater plate of this embodiment. It is a typical top view which illustrates the heater element of this example. It is a typical top view which illustrates the heater element of this example. It is a schematic plan view which illustrates the bypass layer of this example. It is an enlarged view which represents typically a part of heater plate of this example. It is a schematic diagram explaining the shape of the surface of the heater plate of this embodiment. It is a typical sectional view explaining the shape of the surface of the heater plate concerning the modification of this embodiment. It is typical sectional drawing showing the electrostatic chuck concerning the modification of this embodiment. It is a typical top view showing the modification of the 1st support plate of this embodiment. It is a typical top view showing the modification of the 1st support plate of this embodiment. It is typical sectional drawing showing the heater plate of this modification. It is a typical top view showing the specific example of the electric power feeding terminal of this embodiment. It is a typical exploded view showing the modification of the heater plate of this embodiment. It is typical sectional drawing showing the wafer processing apparatus concerning other embodiment of this invention. It is typical sectional drawing showing the modification of the wafer processing apparatus concerning other embodiment of this invention. It is typical sectional drawing showing the modification of the wafer processing apparatus concerning other embodiment of this invention.

1st invention has the 1st main surface in which a process target object is mounted, and the 2nd main surface on the opposite side to the 1st main surface, a ceramic dielectric substrate, and the ceramic dielectric substrate And a heater plate provided between the ceramic dielectric substrate and the base plate, the heater plate including a metal. A first support plate, a second support plate containing metal, a heater element provided between the first support plate and the second support plate and generating heat when an electric current flows; A first resin layer provided between a support plate and the heater element; and a second resin layer provided between the second support plate and the heater element. Electrostatic chuck.

According to this electrostatic chuck, the heater element is provided between the first support plate and the second support plate. Thereby, the uniformity of the temperature distribution in the surface of a heater plate can be improved, and the uniformity of the temperature distribution in the surface of a process target object can be improved. Further, the first support plate and the second support plate can block the heater element from high frequency and suppress the heater element from generating heat to an abnormal temperature.

The second invention is the electrostatic chuck according to the first invention, wherein the first support plate is electrically joined to the second support plate.

This electrostatic chuck can shield the heater element from high frequency. Thereby, it can suppress that a heater element generates heat to abnormal temperature. Moreover, the impedance of the heater plate can be suppressed.

According to a third invention, in the second invention, the area of the region where the first support plate is joined to the second support plate is smaller than the area of the upper surface of the first support plate. The electrostatic chuck is smaller than the area of the lower surface of the support plate.

This electrostatic chuck can shield the heater element from high frequency. Thereby, it can suppress that a heater element generates heat to abnormal temperature. Moreover, the impedance of the heater plate can be suppressed.

In a fourth aspect based on the third aspect, the area of the region where the first support plate is joined to the second support plate is the area of the heater element from the area of the upper surface of the first support plate. The electrostatic chuck is narrower than an area of the difference obtained by subtracting, and smaller than an area of the difference obtained by subtracting the area of the heater element from the area of the lower surface of the second support plate.

According to this electrostatic chuck, for example, it is possible to suppress the heat supplied from the heater element from being transmitted to the second support plate via the joint portion. For example, the uniformity of the temperature distribution in the surface of the processing object can be improved.

According to a fifth invention, in any one of the first to fourth inventions, the upper surface of the first support plate has first irregularities, and the lower surface of the second support plate has second irregularities. It is an electrostatic chuck characterized by having.

According to this electrostatic chuck, since the upper surface of the first support plate has the first unevenness, the bonding area between the first support plate and the heater element can be increased, and the first support The adhesive strength between the plate and the heater element can be improved. Further, since the lower surface of the second support plate has the second unevenness, the bonding area between the second support plate and the heater element can be increased, and the second support plate and the heater element The adhesive strength between them can be improved. Furthermore, since the upper surface of the first support plate has the first unevenness, the distance between the heater element and the object to be processed can be further shortened. Thereby, the speed which raises the temperature of a process target object can be improved.

A sixth invention is the electrostatic chuck according to the fifth invention, wherein the first unevenness follows the shape of the heater element, and the second unevenness follows the shape of the heater element. .

According to this electrostatic chuck, the adhesion area between the first support plate and the heater element can be increased, and the adhesion strength between the first support plate and the heater element can be improved. . Further, the adhesion area between the second support plate and the heater element can be increased, and the adhesion strength between the second support plate and the heater element can be improved. Furthermore, the distance between the heater element and the object to be processed can be further shortened. Thereby, the speed which raises the temperature of a process target object can be improved.

In a sixth aspect based on the sixth aspect, the distance between the first concave-convex concave portion and the second concave-convex concave portion is the distance between the first concave-convex convex portion and the second concave-convex convex portion. An electrostatic chuck characterized by being shorter than the distance between the convex and concave portions.

According to this electrostatic chuck, the adhesion area between the first support plate and the heater element can be increased, and the adhesion strength between the first support plate and the heater element can be improved. . Further, the adhesion area between the second support plate and the heater element can be increased, and the adhesion strength between the second support plate and the heater element can be improved. Furthermore, the distance between the heater element and the object to be processed can be further shortened. Thereby, the speed which raises the temperature of a process target object can be improved.

The eighth invention is the electrostatic chuck according to any one of the fifth to seventh inventions, wherein the height of the first unevenness is different from the height of the second unevenness.

According to this electrostatic chuck, the adhesion area between the first support plate and the heater element can be increased, and the adhesion strength between the first support plate and the heater element can be improved. . Further, the adhesion area between the second support plate and the heater element can be increased, and the adhesion strength between the second support plate and the heater element can be improved. Furthermore, the distance between the heater element and the object to be processed can be further shortened. Thereby, the speed which raises the temperature of a process target object can be improved.

A ninth invention is the electrostatic chuck according to the eighth invention, wherein the height of the first unevenness is lower than the height of the second unevenness.

According to this electrostatic chuck, the adhesion area between the first support plate and the heater element can be increased, and the adhesion strength between the first support plate and the heater element can be improved. . Further, the adhesion area between the second support plate and the heater element can be increased, and the adhesion strength between the second support plate and the heater element can be improved. Furthermore, the distance between the heater element and the object to be processed can be further shortened. Thereby, the speed which raises the temperature of a process target object can be improved.

A tenth aspect of the invention is the electrostatic chuck according to the eighth aspect of the invention, wherein the height of the first unevenness is higher than the height of the second unevenness.

According to this electrostatic chuck, the bonding area between the heater plate and the ceramic dielectric substrate can be widened, and the bonding strength between the heater plate and the ceramic dielectric substrate can be improved.

According to an eleventh aspect of the invention, in any one of the first to tenth aspects, the heater element has a belt-like heater electrode, and the heater electrode is provided in a plurality of regions independently of each other. This is an electrostatic chuck.

According to this electrostatic chuck, since the heater electrodes are provided in a plurality of regions independently of each other, the temperature in the surface of the processing object can be controlled independently for each region. Thereby, it is possible to intentionally make a difference in the in-plane temperature of the processing object (temperature controllability).

A twelfth aspect of the invention is characterized in that, in any one of the first to eleventh aspects, a plurality of the heater elements are provided, and the plurality of heater elements are provided independently in different layers. Electrostatic chuck.

According to this electrostatic chuck, since the heater elements are provided independently in different layers, the in-plane temperature of the processing object can be controlled independently for each region. Thereby, it is possible to intentionally make a difference in the in-plane temperature of the processing object (temperature controllability).

A thirteenth invention is characterized in that, in any one of the first to eleventh inventions, further comprising a conductive bypass layer provided between the heater element and the second support plate. Electrostatic chuck.

According to this electrostatic chuck, a greater degree of freedom can be given to the arrangement of terminals for supplying power to the heater element. By providing the bypass layer, it is not necessary to directly join the terminal having a large heat capacity to the heater element as compared with the case where the bypass layer is not provided. Thereby, the uniformity of the temperature distribution in the surface of a process target object can be improved. Moreover, it is not necessary to join a terminal to a thin heater element compared with the case where a bypass layer is not provided. Thereby, the reliability of a heater plate can be improved.

In a fourteenth aspect based on the thirteenth aspect, the heater element is electrically joined to the bypass layer, and is electrically insulated from the first support plate and the second support plate. This is an electrostatic chuck.

According to this electrostatic chuck, electric power can be supplied from the outside to the heater element via the bypass layer.

The fifteenth invention is the electrostatic chuck according to the thirteenth or fourteenth invention, wherein the thickness of the bypass layer is thicker than the thickness of the first resin layer.

According to this electrostatic chuck, a greater degree of freedom can be given to the arrangement of terminals for supplying power to the heater element. In addition, the electrical resistance of the bypass layer can be suppressed, and the heat generation amount of the bypass layer can be suppressed.

The sixteenth invention is the electrostatic chuck according to any one of the thirteenth to fifteenth inventions, wherein the thickness of the bypass layer is larger than the thickness of the heater element.

According to this electrostatic chuck, a greater degree of freedom can be given to the arrangement of terminals for supplying power to the heater element. In addition, the electrical resistance of the bypass layer can be suppressed, and the heat generation amount of the bypass layer can be suppressed.

The seventeenth invention is the electrostatic chuck according to any one of the thirteenth to sixteenth inventions, wherein the bypass layer is provided between the heater element and the base plate.

According to this electrostatic chuck, the bypass layer suppresses the heat supplied from the heater element from being transmitted to the base plate. That is, the bypass layer has a heat insulating effect on the base plate side as viewed from the bypass layer, and can improve the uniformity of the temperature distribution in the surface of the processing object.

An eighteenth aspect of the invention is characterized in that, in any one of the first to seventeenth aspects of the invention, a conductive bypass layer is further provided between the heater element and the ceramic dielectric substrate. Electrostatic chuck.

According to this electrostatic chuck, the diffusibility of the heat supplied from the heater element can be improved by the bypass layer. That is, the bypass layer improves the thermal diffusivity in the in-plane direction of the process symmetrical object. Thereby, for example, the uniformity of the temperature distribution in the surface of the processing object can be improved.

According to a nineteenth aspect of the invention, in any one of the first to eighteenth aspects, the area of the upper surface of the first support plate is larger than the area of the lower surface of the second support plate. It is a chuck.

According to this electrostatic chuck, a terminal for supplying power to the heater element can be more easily connected on the second support plate side as viewed from the heater element.

In a twentieth aspect according to any one of the first to nineteenth aspects, the first support plate has a plurality of support portions, and the plurality of support portions are provided independently of each other. An electrostatic chuck characterized by the following.

This electrostatic chuck can intentionally provide a temperature difference in the radial direction within the surface of the first support plate (temperature controllability). For example, a temperature difference can be provided in a step shape from the center to the outer periphery within the plane of the first support plate. Thereby, a temperature difference can be intentionally provided within the surface of the processing object (temperature controllability).

A twenty-first aspect of the present invention is the static electricity system according to any one of the first to twentieth aspects, further comprising a power supply terminal that is provided from the heater plate toward the base plate and supplies electric power to the heater plate. It is an electric chuck.

According to this electrostatic chuck, since the power supply terminal is provided from the heater plate toward the base plate, power can be supplied to the power supply terminal from a lower surface side of the base plate through a member called a socket. Thereby, the wiring of the heater is realized while suppressing the supply terminal from being exposed in the chamber in which the electrostatic chuck is installed.

In a twenty-second aspect based on the twenty-first aspect, the power supply terminal includes a pin portion connected to a socket for supplying electric power from the outside, a conductive wire portion thinner than the pin portion, and a support connected to the conductive wire portion. An electrostatic chuck comprising: a portion; and a joint portion connected to the support portion and joined to the heater element.

According to this electrostatic chuck, since the pin portion is thicker than the conducting wire portion, the pin portion can supply a relatively large current to the heater element. Moreover, since the conducting wire portion is thinner than the pin portion, the conducting wire portion is more easily deformed than the pin portion, and the position of the pin portion can be shifted from the center of the joint portion. Thereby, a power feeding terminal can be fixed to a member (for example, a base plate) different from the heater plate. For example, when the support portion is joined to the lead wire portion and the joint portion by welding, joining using laser light, soldering, brazing, etc., the stress applied to the power supply terminal is reduced while the heater element is relaxed. A wider contact area can be ensured.

According to a twenty-third aspect, in any one of the thirteenth to seventeenth aspects, the power supply terminal further includes a power supply terminal that is provided from the heater plate toward the base plate and supplies power to the heater plate. A pin portion connected to a socket for supplying power from, a conductive wire portion thinner than the pin portion, a support portion connected to the conductive wire portion, and a joint portion connected to the support portion and bonded to the bypass layer The electrostatic chuck is configured to supply the electric power to the heater element through the bypass layer.

According to this electrostatic chuck, since the pin portion is thicker than the conducting wire portion, the pin portion can supply a relatively large current to the heater element. Moreover, since the conducting wire portion is thinner than the pin portion, the conducting wire portion is more easily deformed than the pin portion, and the position of the pin portion can be shifted from the center of the joint portion. Thereby, a power feeding terminal can be fixed to a member (for example, a base plate) different from the heater plate. For example, when the support portion is joined to the lead wire portion and the joint portion by welding, joining using laser light, soldering, brazing, or the like, the stress applied to the power supply terminal is reduced while the stress is applied to the bypass layer. A wider contact area can be ensured. In addition, when the support portion is joined to the lead wire portion and the joint portion by, for example, welding, joining using laser light, soldering, brazing, etc., the joint portion having substantially the same thickness as the heater plate and the bypass layer Can be provided.

Embodiments of the present invention will be described below with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and detailed description is abbreviate | omitted suitably.
FIG. 1 is a schematic perspective view showing an electrostatic chuck according to the present embodiment.
FIG. 2 is a schematic cross-sectional view showing the electrostatic chuck according to the present embodiment.
For convenience of explanation, FIG. 1 shows a cross-sectional view of a part of the electrostatic chuck. FIG. 2A is a schematic cross-sectional view taken along the cut plane A1-A1 shown in FIG. 1, for example. FIG. 2B is a schematic enlarged view of the region B1 shown in FIG.

The electrostatic chuck 10 according to the present embodiment includes a ceramic dielectric substrate 100, a heater plate 200, and a base plate 300.
The ceramic dielectric substrate 100 is provided at a position away from the base plate 300. The heater plate 200 is provided between the base plate 300 and the ceramic dielectric substrate 100.

The adhesive 403 is provided between the base plate 300 and the heater plate 200. An adhesive 403 is provided between the heater plate 200 and the ceramic dielectric substrate 100. Examples of the material of the adhesive 403 include heat-resistant resins such as silicone having relatively high thermal conductivity. The thickness of the adhesive 403 is, for example, about 0.1 millimeter (mm) or more and 1.0 mm or less. The thickness of the adhesive 403 is the same as the distance between the base plate 300 and the heater plate 200 or the distance between the heater plate 200 and the ceramic dielectric substrate 100.

The ceramic dielectric substrate 100 is a flat base material made of, for example, a polycrystalline ceramic sintered body, and is opposite to the first main surface 101 on which the processing object W such as a semiconductor wafer is placed, and the first main surface 101. Second main surface 102 on the side.

Here, in the description of the present embodiment, the direction connecting the first main surface 101 and the second main surface 102 is the Z direction, and one of the directions orthogonal to the Z direction is orthogonal to the X direction, the Z direction, and the X direction. The direction to do is referred to as the Y direction.

Examples of the crystal material included in the ceramic dielectric substrate 100 include Al ₂ O ₃ , Y ₂ O _3, and YAG. By using such a material, infrared transmittance, insulation resistance, and plasma durability in the ceramic dielectric substrate 100 can be enhanced.

An electrode layer 111 is provided inside the ceramic dielectric substrate 100. The electrode layer 111 is interposed between the first main surface 101 and the second main surface 102. That is, the electrode layer 111 is formed so as to be inserted into the ceramic dielectric substrate 100. The electrode layer 111 is integrally sintered with the ceramic dielectric substrate 100.

The electrode layer 111 is not limited to be interposed between the first main surface 101 and the second main surface 102, and may be attached to the second main surface 102.

The electrostatic chuck 10 generates a charge on the first main surface 101 side of the electrode layer 111 by applying a suction holding voltage to the electrode layer 111, and holds the processing target W by electrostatic force.

The heater plate 200 generates heat when the heater current flows, and the temperature of the processing object W can be increased as compared with the case where the heater plate 200 does not generate heat.

The electrode layer 111 is provided along the first main surface 101 and the second main surface 102. The electrode layer 111 is an adsorption electrode for adsorbing and holding the processing object W. The electrode layer 111 may be monopolar or bipolar. The electrode layer 111 may be a tripolar type or other multipolar type. The number of the electrode layers 111 and the arrangement of the electrode layers 111 are appropriately selected.

The ceramic dielectric substrate 100 includes a first dielectric layer 107 between the electrode layer 111 and the first main surface 101, and a second dielectric layer 109 between the electrode layer 111 and the second main surface 102. The infrared spectral transmittance of at least the first dielectric layer 107 of the ceramic dielectric substrate 100 is preferably 20% or more. In the present embodiment, the infrared spectral transmittance is a value in terms of a thickness of 1 mm.

Since the infrared spectral transmittance of at least the first dielectric layer 107 of the ceramic dielectric substrate 100 is 20% or more, infrared rays emitted from the heater plate 200 in a state where the processing object W is placed on the first main surface 101. Can efficiently pass through the ceramic dielectric substrate 100. Therefore, it becomes difficult for heat to accumulate in the processing object W, and the controllability of the temperature of the processing object W is improved.

For example, when the electrostatic chuck 10 is used in a chamber in which plasma processing is performed, the temperature of the processing object W is likely to increase as the plasma power increases. In the electrostatic chuck 10 of the present embodiment, the heat transmitted to the processing object W by the plasma power is efficiently transmitted to the ceramic dielectric substrate 100. Further, the heat transmitted to the ceramic dielectric substrate 100 by the heater plate 200 is efficiently transmitted to the processing object W. Therefore, it becomes easy to efficiently transfer the processing object W and maintain it at a desired temperature.

In the electrostatic chuck 10 according to the present embodiment, in addition to the first dielectric layer 107, the infrared spectral transmittance of the second dielectric layer 109 is desirably 20% or more. Since the infrared spectral transmittance of the first dielectric layer 107 and the second dielectric layer 109 is 20% or more, the infrared rays emitted from the heater plate 200 are more efficiently transmitted through the ceramic dielectric substrate 100, and are to be processed. The temperature controllability of the object W can be improved.

The base plate 300 is provided on the second main surface 102 side of the ceramic dielectric substrate 100 and supports the ceramic dielectric substrate 100 via the heater plate 200. A communication path 301 is provided in the base plate 300. That is, the communication path 301 is provided inside the base plate 300. An example of the material of the base plate 300 is aluminum.

The base plate 300 serves to adjust the temperature of the ceramic dielectric substrate 100. For example, when cooling the ceramic dielectric substrate 100, the cooling medium is introduced into the communication path 301, passed through the communication path 301, and the cooling medium is flowed out from the communication path 301. Thereby, the heat of the base plate 300 can be absorbed by the cooling medium, and the ceramic dielectric substrate 100 mounted thereon can be cooled.

On the other hand, when the ceramic dielectric substrate 100 is heated, it is possible to put a heating medium in the communication path 301. Alternatively, a heater (not shown) can be built in the base plate 300. As described above, when the temperature of the ceramic dielectric substrate 100 is adjusted by the base plate 300, the temperature of the processing object W attracted and held by the electrostatic chuck 10 can be easily adjusted.

Further, a convex portion 113 is provided on the first main surface 101 side of the ceramic dielectric substrate 100 as necessary. A groove 115 is provided between the convex portions 113 adjacent to each other. The grooves 115 communicate with each other. A space is formed between the back surface of the processing object W mounted on the electrostatic chuck 10 and the groove 115.

The introduction path 321 that penetrates the base plate 300 and the ceramic dielectric substrate 100 is connected to the groove 115. When a transmission gas such as helium (He) is introduced from the introduction path 321 with the processing object W adsorbed and held, the transmission gas flows into a space provided between the processing object W and the groove 115, and the processing object W can be directly heated or cooled by the transfer gas.

FIG. 3 is a schematic perspective view showing the heater plate of the present embodiment.
FIG. 4 is a schematic perspective view showing the heater plate of the present embodiment.
FIG. 5 is a schematic exploded view showing the heater plate of the present embodiment.
FIG. 6 is a schematic exploded view showing a modification of the heater plate of the present embodiment.
FIG. 3 is a schematic perspective view of the heater plate according to the present embodiment as viewed from the upper surface (the surface on the ceramic dielectric substrate 100 side). FIG. 4A is a schematic perspective view of the heater plate according to the present embodiment as viewed from the lower surface (the surface on the base plate 300 side). FIG. 4B is a schematic enlarged view of the region B2 shown in FIG.

As shown in FIG. 5, the heater plate 200 of the present embodiment includes a first support plate 210, a first resin layer 220, a heater element (heat generation layer) 230, a second resin layer 240, A bypass layer 250, a third resin layer 260, a second support plate 270, and a power supply terminal 280 are included. As shown in FIG. 3, the surface 211 (upper surface) of the first support plate 210 forms the upper surface of the heater plate 200. As shown in FIG. 4, the surface 271 (lower surface) of the second support plate 270 forms the lower surface of the heater plate 200. The first support plate 210 and the second support plate 270 are support plates that support the heater element 230 and the like. In this example, the first support plate 210 and the second support plate 270 include a first resin layer 220, a heater element 230, a second resin layer 240, a bypass layer 250, and a third resin layer 260. , And support these.

The first resin layer 220 is provided between the first support plate 210 and the second support plate 270. The heater element 230 is provided between the first resin layer 220 and the second support plate 270. The second resin layer 240 is provided between the heater element 230 and the second support plate 270. The bypass layer 250 is provided between the second resin layer 240 and the second support plate 270. The third resin layer 260 is provided between the bypass layer 250 and the second support plate 270.

As shown in FIG. 6, the bypass layer 250 and the third resin layer 260 are not necessarily provided. When the bypass layer 250 and the third resin layer 260 are not provided, the second resin layer 240 is provided between the heater element 230 and the second support plate 270. In the following description, a case where the heater plate 200 includes the bypass layer 250 and the third resin layer 260 is taken as an example.

The first support plate 210 has a relatively high thermal conductivity. Examples of the material of the first support plate 210 include a metal containing at least one of aluminum, copper, and nickel, and graphite having a multilayer structure. As the material of the first support plate 210, from the viewpoint of achieving both “in-plane temperature uniformity of the object to be processed” and “high throughput”, which are generally in a trade-off relationship, and from the viewpoint of contamination and magnetism of the chamber, Aluminum or aluminum alloy is suitable. The thickness (length in the Z direction) of the first support plate 210 is, for example, about 0.1 mm or more and 3.0 mm or less. More preferably, the thickness of the first support plate 210 is, for example, about 0.3 mm or more and 1.0 mm or less. The first support plate 210 improves the uniformity of the temperature distribution in the surface of the heater plate 200. The first support plate 210 suppresses the warp of the heater plate 200. The first support plate 210 improves the strength of adhesion between the heater plate 200 and the ceramic dielectric substrate 100.

In the processing process of the processing object W, RF (Radio Frequency) voltage (high frequency voltage) is applied. When the high frequency voltage is applied, the heater element 230 may generate heat under the influence of the high frequency. As a result, the temperature controllability of the heater element 230 decreases.
In contrast, in the present embodiment, the first support plate 210 blocks the heater element 230 and the bypass layer 250 from high frequencies. Thereby, the first support plate 210 can suppress the heater element 230 from generating heat to an abnormal temperature.

The material, thickness, and function of the second support plate 270 can be freely set according to required performance, dimensions, and the like. For example, the material, thickness, and function of the second support plate 270 may be the same as the material, thickness, and function of the first support plate 210, respectively. The first support plate 210 is electrically joined to the second support plate 270. Here, contact is included in the range of “joining” in the present specification. The details of the electrical connection between the second support plate 270 and the first support plate 210 will be described later.

Thus, the first support plate 210 and the second support plate 270 have a relatively high thermal conductivity. Thereby, the first support plate 210 and the second support plate 270 improve the thermal diffusibility of the heat supplied from the heater element 230. Moreover, the 1st support body 210 and the 2nd support body 270 have the moderate thickness and rigidity, and suppress the curvature of the heater plate 200, for example. Furthermore, the first support 210 and the second support 270 improve the shielding performance against an RF voltage applied to, for example, an electrode of a wafer processing apparatus. For example, the influence of the RF voltage on the heater element 230 is suppressed. As described above, the first support 210 and the second support 270 have a function of thermal diffusion, a function of suppressing warpage, and a function of shielding against an RF voltage.

Examples of the material of the first resin layer 220 include polyimide and polyamideimide. The thickness (length in the Z direction) of the first resin layer 220 is, for example, about 0.01 mm or more and 0.20 mm or less. The first resin layer 220 joins the first support plate 210 and the heater element 230 to each other. The first resin layer 220 electrically insulates between the first support plate 210 and the heater element 230. As described above, the first resin layer 220 has a function of electrical insulation and a function of surface bonding.

The material and thickness of the second resin layer 240 are approximately the same as the material and thickness of the first resin layer 220, respectively. The material and thickness of the third resin layer 260 are approximately the same as the material and thickness of the first resin layer 220, respectively.

The second resin layer 240 joins the heater element 230 and the bypass layer 250 to each other. The second resin layer 240 electrically insulates between the heater element 230 and the bypass layer 250. As described above, the second resin layer 240 has a function of electrical insulation and a function of surface bonding.

The third resin layer 260 joins the bypass layer 250 and the second support plate 270 to each other. The third resin layer 260 electrically insulates between the bypass layer 250 and the second support plate 270. Thus, the third resin layer 260 has a function of electrical insulation and a function of surface bonding.

Examples of the material of the heater element 230 include metals including at least one of stainless steel, titanium, chromium, nickel, copper, and aluminum. The thickness (length in the Z direction) of the heater element 230 is, for example, about 0.01 mm or more and 0.20 mm or less. The heater element 230 is electrically joined to the bypass layer 250. On the other hand, the heater element 230 is electrically insulated from the first support plate 210 and the second support plate 270. The details of the electrical connection between the heater element 230 and the bypass layer 250 will be described later.

The heater element 230 generates heat when current flows, and controls the temperature of the processing target W. For example, the heater element 230 heats the processing object W to a predetermined temperature. For example, the heater element 230 makes the temperature distribution in the surface of the processing object W uniform. For example, the heater element 230 intentionally makes a difference in the in-plane temperature of the processing object W.

The bypass layer 250 is disposed substantially parallel to the first support plate 210 and is disposed substantially parallel to the second support plate 270. The bypass layer 250 has a plurality of bypass portions 251. The bypass layer 250 has, for example, eight bypass parts 251. The number of bypass units 251 is not limited to “8”. The bypass layer 250 has a plate shape. On the other hand, the heater element 230 has a belt-like heater electrode 239. When viewed perpendicular to the surface of the bypass layer 250 (surface 251a of the bypass portion 251), the area of the bypass layer 250 is larger than the area of the heater element 230 (area of the heater electrode 239). Details of this will be described later.

The bypass layer 250 has conductivity. The bypass layer 250 is electrically insulated from the first support plate 210 and the second support plate 270. Examples of the material of the bypass layer 250 include metals including stainless steel. The thickness of the bypass layer 250 (the length in the Z direction) is, for example, about 0.03 mm or more and 0.30 mm or less. The bypass layer 250 is thicker than the first resin layer 220. The bypass layer 250 is thicker than the second resin layer 240. The bypass layer 250 is thicker than the third resin layer 260.

For example, the material of the bypass layer 250 is the same as the material of the heater element 230. On the other hand, the bypass layer 250 is thicker than the heater element 230. Therefore, the electrical resistance of the bypass layer 250 is lower than the electrical resistance of the heater element 230. Thereby, even when the material of the bypass layer 250 is the same as the material of the heater element 230, the heat generation of the bypass layer 250 like the heater element 230 can be suppressed. That is, the electrical resistance of the bypass layer 250 can be suppressed, and the heat generation amount of the bypass layer 250 can be suppressed. The means for suppressing the electrical resistance of the bypass layer 250 and suppressing the heat generation amount of the bypass layer 250 may be realized by using a material having a relatively low volume resistivity instead of the thickness of the bypass layer 250. That is, the material of the bypass layer 250 may be different from the material of the heater element 230. Examples of the material of the bypass layer 250 include metals including at least one of stainless steel, titanium, chromium, nickel, copper, and aluminum.

The power supply terminal 280 is electrically joined to the bypass layer 250. In a state where the heater plate 200 is provided between the base plate 300 and the ceramic dielectric substrate 100, the power supply terminal 280 is provided from the heater plate 200 toward the base plate 300. The power supply terminal 280 supplies power supplied from the outside of the electrostatic chuck 10 to the heater element 230 via the bypass layer 250. The power supply terminal 280 may be directly connected to the heater element 230, for example. Thereby, the bypass layer 250 can be omitted.

The heater plate 200 has a plurality of power supply terminals 280. The heater plate 200 shown in FIGS. 3 to 5 has eight power supply terminals 280. The number of power supply terminals 280 is not limited to “8”. One power supply terminal 280 is electrically joined to one bypass unit 251. The hole 273 passes through the second support plate 270. The power feeding terminal 280 is electrically joined to the bypass unit 251 through the hole 273.

As shown by arrows C1 and C2 shown in FIG. 5, when electric power is supplied from the outside of the electrostatic chuck 10 to the power supply terminal 280, current flows from the power supply terminal 280 to the bypass layer 250. As indicated by arrows C <b> 3 and C <b> 4 illustrated in FIG. 5, the current that flows to the bypass layer 250 flows from the bypass layer 250 to the heater element 230. As indicated by arrows C5 and C6 shown in FIG. 5, the current that flows to the heater element 230 flows through a predetermined zone (region) of the heater element 230 and flows from the heater element 230 to the bypass layer 250. Details of the zone of the heater element 230 will be described later. As indicated by arrows C7 and C8 illustrated in FIG. 5, the current that has flowed to the bypass layer 250 flows from the bypass layer 250 to the power supply terminal 280. As indicated by an arrow C9 shown in FIG.

As described above, the junction between the heater element 230 and the bypass layer 250 includes a portion where the current enters the heater element 230 and a portion where the current exits from the heater element 230. That is, a pair exists at the joint between the heater element 230 and the bypass layer 250. Since the heater plate 200 shown in FIGS. 3 to 5 has eight power supply terminals 280, there are four pairs at the junction between the heater element 230 and the bypass layer 250.

According to the present embodiment, the heater element 230 is provided between the first support plate 210 and the second support plate 270. Thereby, the uniformity of the temperature distribution in the surface of the heater plate 200 can be improved, and the uniformity of the temperature distribution in the surface of the processing object W can be improved. Further, the first support plate 210 and the second support plate 270 can block the heater element 230 and the bypass layer 250 from high frequency, and suppress the heater element 230 from generating heat to an abnormal temperature.

As described above, the bypass layer 250 is provided between the heater element 230 and the second support plate 270. That is, the bypass layer 250 is provided between the heater element 230 and the base plate 300. The thermal conductivity of stainless steel is lower than that of aluminum and copper. Therefore, the bypass layer 250 suppresses the heat supplied from the heater element 230 from being transmitted to the second support plate 270. That is, the bypass layer 250 has a heat insulating effect on the second support plate 270 side when viewed from the bypass layer 250, and can improve the uniformity of the temperature distribution in the surface of the processing object W.

The bypass layer 250 can have a greater degree of freedom with respect to the arrangement of the power supply terminals 280. By providing the bypass layer 250, it is not necessary to directly join the power supply terminal having a large heat capacity to the heater element 230 as compared to the case where the bypass layer 250 is not provided. Thereby, the uniformity of the temperature distribution in the surface of the processing target W can be improved. Further, it is not necessary to join the power supply terminal 280 to the thin heater element 230 as compared with the case where the bypass layer 250 is not provided. Thereby, the reliability of the heater plate 200 can be improved.

As described above, the power supply terminal 280 is provided from the heater plate 200 toward the base plate 300. Therefore, electric power can be supplied to the power supply terminal 280 from the side of the lower surface 303 (see FIGS. 2A and 2B) of the base plate 300 through a member called a socket. Thus, the heater wiring is realized while suppressing the power supply terminal 280 from being exposed in the chamber in which the electrostatic chuck 10 is installed.

Next, the manufacturing method of the heater plate 200 of this embodiment is demonstrated, referring drawings.
FIG. 7 is a schematic cross-sectional view illustrating an example of the manufacturing method according to this embodiment.
FIG. 8 is a schematic cross-sectional view illustrating another example of the manufacturing method of this embodiment.
Fig.7 (a) is typical sectional drawing showing the state before joining a bypass layer and a heater element. FIG.7 (b) is typical sectional drawing showing the state after joining a bypass layer and a heater element. FIG. 8 is a schematic cross-sectional view illustrating an example of a joining process between the bypass layer and the power feeding terminal.

In the manufacturing method of the electrostatic chuck 10 according to the present embodiment, for example, the first support plate 210 and the second support plate 270 are manufactured by first machining aluminum. The inspection of the first support plate 210 and the second support plate 270 is performed using, for example, a three-dimensional measuring instrument.

Next, for example, the first resin layer 220, the second resin layer 240, and the third resin layer 260 are manufactured by cutting the polyimide film by laser, machining, die cutting, or melting. The inspection of the first resin layer 220, the second resin layer 240, and the third resin layer 260 is performed using, for example, visual observation.

Next, a heater pattern is formed by cutting stainless steel by etching, machining, die cutting, etc. using photolithography technology or printing technology. Thereby, the heater element 230 is manufactured. Further, the resistance value of the heater element 230 is measured.

Subsequently, as shown in FIGS. 7A and 7B, the heater element 230 and the bypass layer 250 are joined. The heater element 230 and the bypass layer 250 are joined by soldering, brazing, welding, or contact. As shown in FIG. 7A, the second resin layer 240 is provided with a hole 241. The hole 241 passes through the second resin layer 240. For example, the heater element 230 and the bypass layer 250 are joined by performing spot welding from the side of the bypass layer 250 as indicated by an arrow C11 illustrated in FIG.

In addition, joining of the heater element 230 and the bypass layer 250 is not limited to welding. For example, the heater element 230 and the bypass layer 250 may be joined by joining using laser light, soldering, brazing, or contact.

Subsequently, each member of the heater plate 200 is laminated and pressed by a hot press machine.

Subsequently, as shown in FIG. 8, the power feeding terminal 280 and the bypass layer 250 are joined. The power supply terminal 280 and the bypass layer 250 are joined by welding, laser, soldering, brazing, or the like. As shown in FIG. 8, the second support plate 270 is provided with a hole 273. The hole 273 passes through the second support plate 270. This is as described above with reference to FIG. A hole 261 is provided in the third resin layer 260. The hole 261 passes through the third resin layer 260. By performing welding, laser, soldering, brazing, or the like from the second support plate 270 toward the first support plate 210 as indicated by an arrow C <b> 13 illustrated in FIG. 8, the power supply terminal 280 and the bypass layer 250 are performed. And join.

Thus, the heater plate 200 of this embodiment is manufactured.
In addition, inspection etc. are suitably performed with respect to the heater plate 200 after manufacture.

FIG. 9 is a schematic exploded view showing the electrostatic chuck according to the present embodiment.
FIG. 10 is an electric circuit diagram showing the electrostatic chuck according to the present embodiment.
FIG. 10A is an electric circuit diagram illustrating an example in which the first support plate and the second support plate are electrically joined. FIG. 10B is an electric circuit diagram illustrating an example in which the first support plate and the second support plate are not electrically joined.

9 and 10A, the first support plate 210 is electrically joined to the second support plate 270. The first support plate 210 and the second support plate 270 are joined by, for example, welding, joining using laser light, soldering, or contact.

For example, as shown in FIG. 10B, if the first support plate 210 is not electrically and reliably joined to the second support plate 270, the first support plate 210 is the second support plate. 270 may be electrically joined or not electrically joined. Then, the etching rate when plasma is generated may vary. Even if the first support plate 210 is not electrically joined to the second support plate 270, current may flow to the heater element 230 when the plasma is generated, and the heater element 230 may generate heat. In other words, if the first support plate 210 is not securely joined to the second support plate 270, the heater element 230 may generate heat due to a current other than the heater current.

On the other hand, in the electrostatic chuck 10 according to the present embodiment, the first support plate 210 is electrically joined to the second support plate 270 as shown in FIG. As a result, the current flows from the first support plate 210 to the second support plate 270, or the current flows from the second support plate 270 to the first support plate 210, resulting in an etching rate when plasma is generated. The occurrence of variations can be suppressed. Further, the heater element 230 can be prevented from generating heat due to a current other than the heater current.

Furthermore, the heater element 230 and the bypass layer 250 can be shielded from high frequencies. Thereby, it is possible to suppress the heater element 230 from generating heat to an abnormal temperature. Moreover, the impedance of the heater plate 200 can be suppressed.

Next, a specific example of the heater plate 200 of the present embodiment will be described with reference to the drawings.
FIG. 11 is a schematic plan view illustrating a specific example of the heater plate of the present embodiment.
12 and 13 are schematic plan views illustrating the heater element of this example.
FIG. 14 is a schematic plan view illustrating the bypass layer of this example.
FIG. 15 is an enlarged view schematically showing a part of the heater plate of this example.
FIG. 11A is a schematic plan view of the heater plate of this example viewed from above. FIG. 11B is a schematic plan view of the heater plate of this specific example viewed from the lower surface. FIG. 12A is a schematic plan view illustrating an example of a heater element region. FIGS. 12B and 13 are schematic plan views illustrating another example of the heater element region.

As shown in FIG. 14, at least one of the plurality of bypass portions 251 of the bypass layer 250 has a notch 253 at the edge. In the bypass layer 250 shown in FIG. 13, four notches 253 are provided. The number of notches 253 is not limited to “4”.
Since at least one of the plurality of bypass layers 250 has the cutout portion 253, the second support plate 270 can contact the first support plate 210.

As shown in FIGS. 11A and 11B, the first support plate 210 is electrically joined to the second support plate 270 in the regions B11 to B14 and the regions B31 to B34. Yes. Each of the regions B11 to B14 corresponds to each of the regions B31 to B34. That is, in the specific examples shown in FIG. 11A to FIG. 13, the first support plate 210 is electrically joined to the second support plate 270 in four regions, and the second support plate 210 in the eight regions. The support plate 270 is not electrically joined.

FIGS. 15A and 15B are enlarged views showing an example of the region B31 (region B11). FIG. 14A is a schematic plan view of the region B31, and FIG. 15B is a schematic cross-sectional view of the region B31. FIG. 15B schematically shows a cut surface A2-A2 of FIG. Since the other regions B12 to B14 and the regions B32 to B34 are the same as the regions B11 and B31, detailed description thereof is omitted.

As shown in FIGS. 15A and 15B, the region B31 is provided with a bonding region JA. The joint area JA joins the first support plate 210 and the second support plate 270 to each other. The joining area JA is provided on the outer edge of the first support plate 210 and the second support plate 270 corresponding to the notch 253 of the bypass layer 250. The joining area JA is formed by, for example, laser welding from the second support plate 270 side. Thereby, the joining area JA is formed in a spot shape. The bonding area JA may be formed from the first support plate 210 side. In addition, the formation method of joining area | region JA is not restricted to laser welding, Another method may be sufficient. The shape of the bonding area JA is not limited to a spot shape, and may be an elliptical shape, a semicircular shape, a square shape, or the like.

The area of the joint area JA where the first support plate 210 is joined to the second support plate 270 is smaller than the area of the surface 211 (see FIG. 3) of the first support plate 210. The area of the bonding area JA is smaller than the area of the difference obtained by subtracting the area of the heater element 230 from the area of the surface 211. In other words, the area of the bonding area JA is smaller than the area of the area that does not overlap the heater element 230 when projected onto a plane parallel to the surface 211 of the first support plate 210. The area of the joint area JA where the first support plate 210 is joined to the second support plate 270 is smaller than the area of the surface 271 of the second support plate 270 (see FIG. 4A). The area of the bonding area JA is smaller than the area of the difference obtained by subtracting the area of the heater element 230 from the area of the surface 271. In other words, the area of the bonding area JA is smaller than the area of the area that does not overlap the heater element 230 when projected onto a plane parallel to the surface 271 of the second support plate 270.

The diameter of the joining area JA formed in a spot shape is, for example, 1 mm (0.5 mm or more and 3 mm or less). On the other hand, the diameters of the first support plate 210 and the second support plate 270 are, for example, 300 mm. The diameters of the first support plate 210 and the second support plate 270 are set according to the processing object W to be held. Thus, the area of the bonding area JA is sufficiently smaller than the area of the surface 211 of the first support plate 210 and the area of the surface 271 of the second support plate 270. The area of the bonding region JA is, for example, 1/5000 or less of the area of the surface 211 (area of the surface 271). Here, the area of the bonding area JA is more specifically the area when projected onto a plane parallel to the surface 211 of the first support plate 210. In other words, the area of the bonding area JA is an area in a top view.

In this example, four joint areas JA corresponding to the areas B11 to B14 and the areas B31 to B34 are provided. The number of joining areas JA is not limited to four. The number of the joining areas JA may be an arbitrary number. For example, twelve bonding areas JA may be provided on the first support plate 210 and the second support plate 270 every 30 °. Further, the shape of the bonding area JA is not limited to a spot shape. The shape of the bonding area JA may be elliptical, square, linear, or the like. For example, the joining area JA may be formed in an annular shape along the outer edges of the first support plate 210 and the second support plate 270.

The second support plate 270 has a hole 273 (see FIG. 4B and FIG. 8). On the other hand, the first support plate 210 does not have a hole through which the power supply terminal 280 passes. Therefore, the area of the surface 211 of the first support plate 210 is larger than the area of the surface 271 of the second support plate 270.

The heater element 230 has, for example, a belt-like heater electrode 239. In the specific example shown in FIG. 12A, the heater electrode 239 is arranged to draw a substantially circle. The heater electrode 239 is disposed in the first region 231, the second region 232, the third region 233, and the fourth region 234. The first region 231 is located at the center of the heater element 230. The second region 232 is located outside the first region 231. The third region 233 is located outside the second region 232. The fourth region 234 is located outside the third region 233.

The heater electrode 239 disposed in the first region 231 is not electrically joined to the heater electrode 239 disposed in the second region 232. The heater electrode 239 disposed in the second region 232 is not electrically joined to the heater electrode 239 disposed in the third region 233. The heater electrode 239 disposed in the third region 233 is not electrically joined to the heater electrode 239 disposed in the fourth region 234. That is, the heater electrode 239 is provided in a plurality of regions in an independent state.

In the specific example shown in FIG. 12B, the heater electrode 239 is arranged so as to draw at least a part of a substantially fan shape. The heater electrode 239 includes a first region 231a, a second region 231b, a third region 231c, a fourth region 231d, a fifth region 231e, a sixth region 231f, and a seventh region. The region 232a, the eighth region 232b, the ninth region 232c, the tenth region 232d, the eleventh region 232e, and the twelfth region 232f are arranged. The heater electrode 239 arranged in an arbitrary region is not electrically joined to the heater electrode 239 arranged in another region. That is, the heater electrode 239 is provided in a plurality of regions in an independent state. As shown in FIGS. 12A and 12B, the region where the heater electrode 239 is disposed is not particularly limited.

In the specific example shown in FIG. 13, the heater element 230 has more areas. In the heater element 230 of FIG. 13, the first region 231 shown in FIG. 12A is further divided into four regions 231a to 231d. Further, the second area 232 shown in FIG. 12A is further divided into eight areas 232a to 232h. Further, the third area 233 shown in FIG. 12A is further divided into eight areas 233a to 233h. The fourth area 234 shown in FIG. 12A is further divided into 16 areas 234a to 234p. As described above, the number and shape of the regions of the heater element 230 in which the heater electrode 239 is disposed may be arbitrary.

As shown in FIG. 14A, the bypass portion 251 of the bypass layer 250 has a fan shape. A plurality of fan-shaped bypass portions 251 are arranged apart from each other, and the bypass layer 250 has a substantially circular shape as a whole. As shown in FIG. 14A, the separation portion 257 between the adjacent bypass portions 251 extends in the radial direction from the center 259 of the bypass layer 250. In other words, the separation portion 257 between the adjacent bypass portions 251 extends radially from the center 259 of the bypass layer 250. The area of the surface 251 a of the bypass part 251 is larger than the area of the separation part 257. The area of the bypass layer 250 (area of the surface 251a of the bypass portion 251) is larger than the area of the heater element 230 (area of the heater electrode 239).

14B, the shape of the plurality of bypass portions 251 of the bypass layer 250 may be, for example, a curved fan shape. Thus, the number and shape of the plurality of bypass portions 251 provided in the bypass layer 250 may be arbitrary.

In the following description regarding FIG. 11 to FIG. 14, the region of the heater element 230 shown in FIG. The heater electrode 239 is disposed so as to draw a substantially circle, and a plurality of fan-shaped bypass portions 251 are arranged apart from each other. Therefore, when viewed perpendicular to the surface 251 a of the bypass portion 251, the heater electrode 239 intersects with the separation portion 257 between the adjacent bypass portions 251. Further, when viewed perpendicular to the surface 251 a of the bypass portion 251, each region of the adjacent heater element 230 (the first region 231, the second region 232, the third region 233, and the fourth region 234). ) Between the adjacent bypass portions 251 intersects with the separation portion 257 between the adjacent bypass portions 251.

As shown in FIGS. 11A and 11B, a plurality of imaginary lines connecting each of the joint portions 255a to 255h between the heater element 230 and the bypass layer 250 and the center 203 of the heater plate 200 are , Do not overlap each other. In other words, the joint portions 255 a to 255 h between the heater element 230 and the bypass layer 250 are arranged in different directions as viewed from the center 203 of the heater plate 200. As shown in FIG. 11B, the power supply terminal 280 exists on an imaginary line that connects each of the joint portions 255a to 255h and the center 203 of the heater plate 200.

The joint portions 255 a and 255 b are portions that join the heater electrode 239 and the bypass layer 250 disposed in the first region 231. The joint portions 255a and 255b correspond to the first region 231. One of the joint portion 255a and the joint portion 255b is a portion where current enters the heater element 230. The other of the joining portion 255a and the joining portion 255b is a portion where current flows out of the heater element 230.

The joint portions 255 c and 255 d are portions that join the heater electrode 239 and the bypass layer 250 disposed in the second region 232. The joint portions 255 c and 255 d correspond to the second region 232. One of the joint portion 255c and the joint portion 255d is a portion where current enters the heater element 230. The other of the joining portion 255c and the joining portion 255d is a portion where current flows out of the heater element 230.

The joint portions 255e and 255f are portions that join the heater electrode 239 and the bypass layer 250 disposed in the third region 233. The joint portions 255e and 255f correspond to the third region 233. One of the joint portion 255e and the joint portion 255f is a portion where current enters the heater element 230. The other of the joining portion 255e and the joining portion 255f is a portion where the current exits from the heater element 230.

The joint portions 255g and 255h are portions that join the heater electrode 239 and the bypass layer 250 disposed in the fourth region 234. The joint portions 255g and 255h correspond to the fourth region 234. One of the junction 255g and the junction 255h is a portion where current enters the heater element 230. The other of the joining portion 255g and the joining portion 25h is a portion where current flows out of the heater element 230.

The joint portions 255a and 255b exist on a circle different from the circle passing through the joint portions 255c and 255d with the center 203 of the heater plate 200 as the center. The joint portions 255a and 255b exist on a circle different from the circle passing through the joint portions 255e and 255f with the center 203 of the heater plate 200 as the center. The joints 255a and 255b exist on a circle different from the circle passing through the joints 255g and 255h with the center 203 of the heater plate 200 as the center.
The joint portions 255c and 255d exist on a circle different from the circle passing through the joint portions 255e and 255f with the center 203 of the heater plate 200 as the center. The joint portions 255c and 255d exist on a circle different from the circle passing through the joint portions 255g and 255h with the center 203 of the heater plate 200 as the center.
The joint portions 255e and 255f exist on a circle different from the circle passing through the joint portions 255g and 255h with the center 203 of the heater plate 200 as the center.

11A and 11B, the heater plate 200 has a lift pin hole 201. As shown in FIG. In the specific examples shown in FIGS. 11A and 11B, the heater plate 200 has three lift pin holes 201. The number of lift pin holes 201 is not limited to “3”. The power supply terminal 280 is provided in a region on the side of the center 203 of the heater plate 200 when viewed from the lift pin hole 201.

According to this specific example, since the heater electrode 239 is arranged in a plurality of regions, the temperature in the surface of the processing object W can be controlled independently for each region. Thereby, it is possible to intentionally make a difference in the in-plane temperature of the processing object W (temperature controllability).

FIG. 16 is a schematic diagram for explaining the shape of the surface of the heater plate of the present embodiment.
FIG. 16A is a graph illustrating an example of a result of measurement of the shape of the surface 271 of the second support plate 270 by the inventor. FIG. 16B is a schematic cross-sectional view illustrating the shape of the surface of the heater plate 200 of the present embodiment.

As described above with reference to FIG. 8, each member of the heater plate 200 is pressed by a hot press machine in a stacked state. At this time, as shown in FIG. 16B, the first unevenness is generated on the surface 211 (upper surface) of the first support plate 210. The second unevenness is generated on the surface 271 (lower surface) of the second support plate 270. In addition, a third unevenness is generated on the surface 213 (lower surface) of the first support plate 210. A fourth unevenness is generated on the surface 275 (upper surface) of the second support plate 270.

The inventor measured the shape of the surface 271 of the second support plate 270. An example of the measurement result is as shown in FIG. As shown in FIGS. 16A and 16B, the shape of the surface 211 (upper surface) of the first support plate 210 and the shape of the surface 271 of the second support plate 270 are the shapes of the heater element 230. Alternatively, the heater element 230 is arranged. The shape of the heater element 230 refers to the thickness of the heater element 230 and the width of the heater element 230 (the width of the heater electrode 239).

Z between the concave portion 211a (first concave / convex concave portion 211a) of the surface 211 of the first support plate 210 and the concave portion 271a (second concave / convex concave portion 271a) of the surface 271 of the second support plate 270. The distance D1 in the direction is such that the convex portion 211b (first concave / convex convex portion 211b) of the surface 211 of the first support plate 210 and the convex portion 271b (second concave / convex portion of the surface 271 of the second supporting plate 270). It is shorter than the distance D2 in the Z direction between the convex portion 271b).

The distance D3 in the Z direction between the concave portion 211a of the surface 211 of the first support plate 210 and the convex portion 211b of the surface 211 of the first support plate 210 (the uneven height of the surface 211 of the first support plate 210) (The height of the first unevenness) is a distance D4 (Z4) between the concave portion 271a of the surface 271 of the second support plate 270 and the convex portion 271b of the surface 271 of the second support plate 270. The unevenness height of the surface 271 of the second support plate 270 is shorter than the height of the second unevenness. That is, the unevenness height (first unevenness height) of the surface 211 of the first support plate 210 is higher than the unevenness height (second unevenness height) of the surface 271 of the second support plate 270. Low.

The width of the concave portion 271a of the surface 271 of the second support plate 270 is approximately the same as the width of the region between the two adjacent heater electrodes 239 (the slit portion of the heater element 230). The width of the concave portion 271a of the surface 271 of the second support plate 270 is, for example, not less than 0.25 times and not more than 2.5 times the width of the region between two adjacent heater electrodes 239.

The width of the convex portion 271b of the surface 271 of the second support plate 270 is approximately the same as the width of the heater electrode 239. The width of the convex portion 271b of the surface 271 of the second support plate 270 is, for example, not less than 0.8 times and not more than 1.2 times the width of the heater electrode 230.

Also, the uneven height D4 of the surface 271 of the second support plate 270 is approximately the same as the thickness of the heater element 230 (the thickness of the heater electrode 239). The uneven height D4 of the second support plate 270 is not less than 0.8 times and not more than 1.2 times the thickness of the heater element 230.

Similarly, the width of the recess 211a of the surface 211 of the first support plate 210 is approximately the same as the width of the region between the two adjacent heater electrodes 239. The width of the convex portion 211 b of the surface 211 of the first support plate 210 is approximately the same as the width of the heater electrode 239. On the other hand, the uneven height D 3 of the surface 211 of the first support plate 210 is lower than the thickness of the heater element 230.

The height of the surface 271 of the second support plate 270 changes gradually from the convex portion 271b toward the adjacent concave portion 271a. For example, the height of the surface 271 of the second support plate 270 continuously decreases from the center in the width direction of the convex portion 271b toward the center in the width direction of the adjacent concave portion 271a. More specifically, the center in the width direction of the convex portion 271b is a position overlapping with the center in the width direction of the heater electrode 239 in the surface 271 in the Z direction. More specifically, the center in the width direction of the concave portion 271a is a position overlapping in the Z direction with the center in the width direction of the region between the two adjacent heater electrodes 239 in the surface 271.

Thus, the height of the surface 271 of the second support plate 270 changes in a wave shape with the portion overlapping with the heater electrode 239 as the apex and the portion not overlapping with the heater electrode 239 as the lowest point. Similarly, the height of the surface 211 of the first support plate 210 changes in a wave shape with the portion overlapping the heater electrode 239 as the apex and the portion not overlapping with the heater electrode 239 as the lowest point.

According to this embodiment, since the surface 211 of the first support plate 210 has the first unevenness, the bonding area between the first support plate 210 and the heater element 230 can be further increased, and the first The adhesive strength between the one support plate 210 and the heater element 230 can be improved. Moreover, the adhesion area of the 1st support plate 210 and the adhesive agent 403 can be made wider according to the 1st unevenness | corrugation. Thereby, the joint strength between the first support plate 210 and the adhesive 403 can also be improved. Further, since the first support plate 210 has irregularities, the rigidity of the first support plate 210 is increased. For this reason, even if the 1st support plate 210 is thin, the curvature and deformation | transformation of the heater plate 200 can be reduced. Thereby, for example, it is possible to achieve both “reduction of the warpage of the heater plate” and “reduction of heat capacity” that affect high throughput, which are generally in a trade-off relationship. In addition, since the surface 271 of the second support plate 270 has the second unevenness, the adhesion area between the second support plate 270 and the bypass layer 250 can be increased, and the second support plate 270 can be increased. And the adhesive strength between the bypass layer 250 can be improved. Moreover, the adhesion area of the 2nd support plate 270 and the adhesive agent 403 can be made wider according to the 2nd unevenness | corrugation. Thereby, the joint strength between the second support plate 270 and the adhesive 403 can also be improved. In addition, since the second support plate 270 has irregularities, the rigidity of the second support plate 270 increases. For this reason, even if the 2nd support plate 270 is thin, the curvature and deformation | transformation of the heater plate 200 can be reduced. Thereby, for example, it is possible to achieve both “reduction of the warpage of the heater plate” and “reduction of heat capacity” that affect high throughput, which are generally in a trade-off relationship. Furthermore, since the surface 211 of the first support plate 210 has the first unevenness, the distance between the heater element 230 and the processing object W can be further shortened. Thereby, the speed which raises the temperature of the processing target object W can be improved.

FIG. 17A to FIG. 17C are schematic cross-sectional views illustrating the shape of the surface of the heater plate according to the modification of the present embodiment.
Also in the heater plate 200 shown in FIGS. 17A to 17C, the first to fourth irregularities are generated in the same manner as described with reference to FIG.
As shown in FIG. 17A, the distance D1a in the Z direction between the concave portion 211a and the concave portion 271a is shorter than the distance D2a in the Z direction between the convex portion 211b and the convex portion 271b. .

In the example shown in FIG. 17A, unlike the example shown in FIG. 16B, the distance D3a in the Z direction between the concave portion 211a and the convex portion 211b (of the surface 211 of the first support plate 210). Unevenness height: the height of the first unevenness is the distance D4a in the Z direction between the recesses 271a and 271b (the unevenness height of the surface 271 of the second support plate 270: the height of the second unevenness). Longer than). That is, in this example, the unevenness height (the height of the first unevenness) of the surface 211 of the first support plate 210 is the unevenness height (the height of the second unevenness) of the surface 271 of the second support plate 270. Is higher than

Further, the uneven height D3a of the surface 211 of the first support plate 210 is approximately the same as the thickness of the heater element 230, for example, 0.8 times or more and 1.2 times or less of the thickness of the heater element 230. . On the other hand, the uneven height D4a of the surface 271 of the second support substrate 270 is lower than the thickness of the heater element 230.

Note that the width of the recess 211a and the width of the recess 271a are approximately the same as the width of the region between two adjacent heater electrodes 239, respectively. The width of the convex portion 211b and the width of the convex portion 271b are approximately the same as the width of the heater electrode 239, respectively.

Also in the example shown in FIG. 17A, the height of the surface 271 of the second support plate 270 and the height of the surface 211 of the first support substrate 210 are the same as in the description related to FIG. Each of them changes in a wave shape. By providing the first unevenness and the second unevenness as described above, the bonding area is increased and the bonding strength is improved.

As in the example shown in FIG. 16B, when the height of the second unevenness (distance D4) is higher than the height of the first unevenness (distance D3), the heater plate 200, the base plate 300, The bonding area can be increased. Thereby, the adhesive strength between the heater plate 200 and the base plate 300 can be improved.

On the other hand, when the first unevenness height (distance D3a) is higher than the second unevenness height (distance D4a) as in the example shown in FIG. The bonding area with the dielectric substrate 100 can be increased. Thereby, the adhesive strength between the heater plate 200 and the ceramic dielectric substrate 100 can be improved.

In the example illustrated in FIG. 17A, the heater element 230 is provided between the first support plate 210 and the bypass layer 250. In this case, the diffusibility of heat supplied from the heater element 230 to the base plate 300 can be improved. Specifically, the thermal diffusibility in the in-plane direction (horizontal direction) of the processing target W can be improved. For example, the heat supplied to the refrigerant flowing in the base plate 300 becomes more uniform in the in-plane direction. Thereby, an in-plane temperature difference caused by the base plate 300 (refrigerant) can be reduced.

Also in the heater plate 200 shown in FIGS. 17B and 17C, the first support plate 210, the first resin layer 220, the second resin layer 240, the third resin layer 260, and the heater element are also provided. 230, a bypass layer 250, and a second support plate 270 are provided. However, the example shown in FIGS. 17B and 17C is different from the heater plate 200 shown in FIG. 17A in the stacking order.

In the example shown in FIGS. 17B and 17C, the bypass layer 250 is provided between the first support plate 210 and the heater element 230. Thereby, the diffusibility of the heat supplied from the heater element 230 to the processing object W side can be improved. Specifically, the thermal diffusibility in the in-plane direction (horizontal direction) of the processing target W can be improved. For example, the in-plane temperature difference caused by the heat generated by the heater element 230 can be reduced. Details of this structure will be described later with reference to FIG.

Also in the example shown in FIG. 17B, the distance D1b in the Z direction between the recess 211a and the recess 271a is shorter than the distance D2b in the Z direction between the protrusion 211b and the protrusion 271b.

Further, the distance D3b in the Z direction between the concave portion 211a and the convex portion 211b (the unevenness height of the surface 211 of the first support plate 210: the height of the first unevenness) is the distance between the concave portion 271a and the convex portion 271b. It is longer than the distance D4b in the Z direction (the height of the unevenness of the surface 271 of the second support plate 270: the height of the second unevenness). That is, in this example, the unevenness height (the height of the first unevenness) of the surface 211 of the first support plate 210 is the unevenness height (the height of the second unevenness) of the surface 271 of the second support plate 270. Is higher than

The unevenness height D3b of the surface 211 of the first support plate 210 is approximately the same as the thickness of the heater element 230, and is, for example, 0.8 times or more and 1.2 times or less the thickness of the heater element 230. On the other hand, the uneven height D4b of the surface 271 of the second support substrate 270 is lower than the thickness of the heater element 230.

In addition, about the width | variety of the recessed part 211a, the recessed part 271a, the convex part 211b, and the convex part 271b, it is the same as that of the description regarding Fig.17 (a).

In the heater plate 200 shown in FIG. 17B, the first unevenness height (distance D3b) is higher than the second unevenness height (distance D4b), which is the same as in the case of FIG. Further, the adhesive strength between the heater plate 200 and the ceramic dielectric substrate 100 can be improved.

For example, the temperature difference (relative displacement) between the heater plate 200 and the ceramic dielectric substrate 100 may easily increase due to heat transferred from the processing object W to the electrostatic chuck along with the plasma processing. In such a case, the reliability is increased by improving the adhesive strength between the heater plate 200 and the ceramic dielectric substrate 100 as in the case of the heater plate shown in FIGS. 17 (a) and 17 (b). Can be improved.

Also in the example shown in FIG. 17C, the distance D1c in the Z direction between the recess 211a and the recess 271a is shorter than the distance D2c in the Z direction between the protrusion 211b and the protrusion 271b.

Further, the distance D3c in the Z direction between the concave portion 211a and the convex portion 211b (the unevenness height of the surface 211 of the first support plate 210: the height of the first unevenness) is the distance between the concave portion 271a and the convex portion 271b. It is shorter than the distance D4c in the Z direction (heave height of the surface 271 of the second support plate 270: height of the second bump). That is, in this example, the unevenness height (the height of the first unevenness) of the surface 211 of the first support plate 210 is the unevenness height (the height of the second unevenness) of the surface 271 of the second support plate 270. Lower).

The unevenness height D4c of the surface 271 of the second support plate 270 is approximately the same as the thickness of the heater element 230, and is, for example, 0.8 times or more and 1.2 times or less the thickness of the heater element 230. On the other hand, the uneven height D 3 c of the surface 211 of the first support substrate 210 is lower than the thickness of the heater element 230.

In addition, about the width | variety of the recessed part 211a, the recessed part 271a, the convex part 211b, and the convex part 271b, it is the same as that of the description regarding Fig.17 (a).

In the heater plate 200 shown in FIG. 17C, the second unevenness height (distance D4c) is higher than the first unevenness height (distance D3c), which is similar to the case of FIG. 16B. In addition, the bonding area between the heater plate 200 and the base plate can be increased. Thereby, the adhesive strength between the heater plate 200 and the base plate 300 can be improved.

For example, the temperature difference (relative displacement) between the heater plate 200 and the base plate 300 is likely to increase due to heat generated by the heater element 230 or the like. In such a case, the reliability can be greatly improved by improving the adhesive strength between the heater plate 200 and the base plate 300 as shown in FIG.

Note that the heights of the first and second irregularities can be controlled, for example, depending on the processing conditions of hot pressing. As an example, the first and second uneven heights can be controlled by the material and hardness of a member that presses the laminate from above and a member that presses the laminate from below.

FIG. 18 is a schematic cross-sectional view showing an electrostatic chuck according to a modification of the present embodiment.
FIG. 18A is a schematic cross-sectional view showing an electrostatic chuck according to a modification of the present embodiment. FIG. 18B is a schematic cross-sectional view showing the heater plate of this modification. FIGS. 18A and 18B correspond to, for example, schematic cross-sectional views taken along section A1-A1 shown in FIG.

The electrostatic chuck 10a shown in FIG. 18A includes a ceramic dielectric substrate 100, a heater plate 200a, and a base plate 300. The ceramic dielectric substrate 100 and the base plate 300 are as described above with reference to FIGS.

As shown in FIG. 18B, the heater plate 200a of this example has a plurality of heater elements. The heater plate 200a shown in FIG. 18B includes a first resin layer 220, a first heater element (heat generation layer) 230a, a second resin layer 240, and a second heater element (heat generation layer). 230 b, a third resin layer 260, a bypass layer 250, a fourth resin layer 290, and a second support plate 270.

The first resin layer 220 is provided between the first support plate 210 and the second support plate 270. The first heater element 230 a is provided between the first resin layer 220 and the second support plate 270. The second resin layer 240 is provided between the first heater element 230 a and the second support plate 270. The second heater element 230 b is provided between the second resin layer 240 and the second support plate 270. The third resin layer 260 is provided between the second heater element 230 b and the second support plate 270. The bypass layer 250 is provided between the third resin layer 260 and the second support plate 270. The fourth resin layer 290 is provided between the bypass layer 250 and the second support plate 270. That is, in this specific example, the first heater element 230a is provided in a state independent of the second heater element 230b in a different layer.

The respective materials of the first support plate 210, the first resin layer 220, the second resin layer 240, the third resin layer 260, the bypass layer 250, and the second support plate 270, The thickness and function are as described above with respect to FIGS. The materials, thicknesses, and functions of the first heater element 230a and the second heater element 230b are the same as those of the heater element 230 described above with reference to FIGS. The fourth resin layer 290 is the same as the first resin layer 220 described above with reference to FIGS.

According to this modification, since the first heater element 230a is independently arranged in a layer different from the second heater element 230b, the temperature in the surface of the processing object W is independent for each predetermined region. Can be controlled.

FIGS. 19 and 20 are schematic plan views showing modifications of the first support plate of the present embodiment.

FIG. 21 is a schematic cross-sectional view showing a heater plate according to this modification.
FIG. 19A shows an example in which the first support plate is divided into a plurality of support portions. FIG. 19B and FIG. 20 show another example in which the first support plate is divided into a plurality of support portions.

In FIG. 21, for convenience of explanation, the heater plate shown in FIG. 19A and the graph of the temperature of the upper surface of the first support plate are shown together. The graph shown in FIG. 21 is an example of the temperature of the upper surface of the first support plate. The horizontal axis of the graph shown in FIG. 21 represents the position of the upper surface of the first support plate 210a. The vertical axis of the graph shown in FIG. 21 represents the temperature of the upper surface of the first support plate 210a. In FIG. 21, for convenience of explanation, the bypass layer 250 and the third resin layer 260 are omitted.

In the modification shown in FIGS. 19A and 19B, the first support plate 210a is divided into a plurality of support portions. More specifically, in the modification shown in FIG. 19A, the first support plate 210a is concentrically divided into a plurality of support portions, and includes a first support portion 216 and a second support portion. 217, a third support portion 218, and a fourth support portion 219. In the modification shown in FIG. 19B, the first support plate 210b is concentrically and radially divided into a plurality of support portions, and includes a first support portion 216a, a second support portion 216b, 3 support part 216c, 4th support part 216d, 5th support part 216e, 6th support part 216f, 7th support part 217a, 8th support part 217b, and 9th It has a support part 217c, a tenth support part 217d, an eleventh support part 217e, and a twelfth support part 217f.

In the modification shown in FIG. 20, the first support plate 210c has more support portions. In the first support plate 210c of FIG. 20, the first support portion 216 shown in FIG. 19A is further divided into four support portions 216a to 216d. Further, the second support portion 217 shown in FIG. 19A is further divided into eight support portions 217a to 217h. Further, the third support portion 218 shown in FIG. 19A is further divided into eight regions 218a to 218h. The fourth support portion 219 shown in FIG. 19A is further divided into 16 support portions 219a to 219p. Thus, the number and shape of the support portions provided on the first support plate 210 may be arbitrary.

The first resin layer 220, the heater element 230, the second resin layer 240, the bypass layer 250, the third resin layer 260, the second support plate 270, and the power supply terminal 280 are respectively As described above with reference to FIGS.

In the following description regarding FIGS. 19A to 21, the first support plate 210a shown in FIG. 19A is taken as an example. As shown in FIG. 21, the first support portion 216 is provided on the first region 231 of the heater element 230 and corresponds to the first region 231 of the heater element 230. The second support portion 217 is provided on the second region 232 of the heater element 230 and corresponds to the second region 232 of the heater element 230. The third support portion 218 is provided on the third region 233 of the heater element 230 and corresponds to the third region 233 of the heater element 230. The fourth support portion 219 is provided on the fourth region 234 of the heater element 230 and corresponds to the fourth region 234 of the heater element 230.

The first support part 216 is not electrically joined to the second support part 217. The second support part 217 is not electrically joined to the third support part 218. The third support part 218 is not electrically joined to the fourth support part 219.

According to this modification, a temperature difference in the radial direction can be intentionally provided in the plane of the first support plates 210a, 210b, 210c (temperature controllability). For example, as shown in the graph diagram of FIG. 21, a temperature difference can be provided stepwise from the first support portion 216 to the fourth support portion 219. Thereby, a temperature difference can be intentionally provided in the surface of the processing object W (temperature controllability).

FIG. 22 is a schematic plan view illustrating a specific example of the power feeding terminal of the present embodiment.
FIG. 22A is a schematic plan view showing a power supply terminal of this example. FIG. 22B is a schematic plan view illustrating the power feeding terminal joining method according to this example.

The power supply terminal 280 shown in FIGS. 22A and 22B includes a pin portion 281, a conductive wire portion 283, a support portion 285, and a joint portion 287. The pin portion 281 is connected to a member called a socket or the like. The socket supplies power from the outside of the electrostatic chuck 10. The conducting wire part 283 is connected to the pin part 281 and the support part 285. The support portion 285 is connected to the conductor portion 283 and the joint portion 287. The joining portion 287 is joined to the heater element 230 or the bypass layer 250 as indicated by an arrow C14 shown in FIG.

The conducting wire portion 283 relieves stress applied to the power supply terminal 280. That is, the pin portion 281 is fixed to the base plate 300. On the other hand, the joint portion 287 is joined to the heater element 230 or the bypass layer 250. A temperature difference is generated between the base plate 300 and the heater element 230 or the bypass layer 250. Therefore, a difference in thermal expansion occurs between the base plate 300 and the heater element 230 or the bypass layer 250. Therefore, stress due to a difference in thermal expansion may be applied to the power supply terminal 280. The stress resulting from the difference in thermal expansion is applied in the radial direction of the base plate 300, for example. The conductor portion 283 can relieve this stress. The joining portion 287 and the heater element 230 or the bypass layer 250 are joined by welding, joining using laser light, soldering, brazing, or the like.

The material of the pin portion 281 includes, for example, molybdenum. Examples of the material of the conductive wire portion 283 include copper. The diameter D5 of the conducting wire part 283 is smaller than the diameter D8 of the pin part 281. The diameter D5 of the conducting wire part 283 is, for example, about 0.3 mm or more and 2.0 mm or less. Examples of the material of the support portion 285 include stainless steel. The thickness D6 (length in the Z direction) of the support portion 285 is, for example, about 0.5 mm or more and 2.0 mm or less. Examples of the material of the bonding portion 287 include stainless steel. A thickness D7 (length in the Z direction) of the joint portion 287 is, for example, about 0.05 mm or more and 0.50 mm or less.

According to this specific example, since the diameter D8 of the pin portion 281 is larger than the diameter D5 of the conducting wire portion 283, the pin portion 281 can supply a relatively large current to the heater element 230. Moreover, since the diameter D5 of the conducting wire part 283 is smaller than the diameter D8 of the pin part 281, the conducting wire part 283 is easier to deform than the pin part 281, and the position of the pin part 281 can be shifted from the center of the joint part 287. . Thereby, the power supply terminal 280 can be fixed to a member (for example, the base plate 300) different from the heater plate 200.

The support portion 285 is joined to the conductor portion 283 and the joint portion 287 by, for example, welding, joining using laser light, soldering, brazing, or the like. Thereby, a wider contact area with respect to the heater element 230 or the bypass layer 250 can be ensured while relaxing the stress applied to the power supply terminal 280.

FIG. 23 is a schematic exploded view showing a modification of the heater plate of the present embodiment.
As shown in FIG. 23, in this example, the bypass layer 250 is provided between the first support plate 210 and the heater element 230. More specifically, the bypass layer 250 is provided between the first support plate 210 and the first resin layer 220, and the third resin layer 260 is provided between the first support plate 210 and the bypass layer 250. Provided.

Thus, the bypass layer 250 may be provided between the first support plate 210 and the heater element 230. That is, the bypass layer 250 may be provided between the heater element 230 and the ceramic dielectric substrate 100.

Also in this case, the diffusibility of the heat supplied from the heater element 230 can be improved by the bypass layer 250. For example, the thermal diffusibility in the in-plane direction (horizontal direction) of the processing object W can be improved. Thereby, the uniformity of the temperature distribution in the surface of the process target W can be improved, for example.

Note that the bypass layer 250 may be provided, for example, both between the first support plate 210 and the heater element 230 and between the heater element 230 and the second support plate 270. That is, the heater plate 200 includes two bypass layers 250 provided between the first support plate 210 and the heater element 230 and between the heater element 230 and the second support plate 270, respectively. May be.

FIG. 24 is a schematic sectional view showing a wafer processing apparatus according to another embodiment of the present invention.
The wafer processing apparatus 500 according to the present embodiment includes a processing container 501, an upper electrode 510, and the electrostatic chuck (for example, the electrostatic chuck 10) described above with reference to FIGS. A processing gas inlet 502 for introducing processing gas into the inside is provided on the ceiling of the processing container 501. The bottom plate of the processing vessel 501 is provided with an exhaust port 503 for exhausting the inside under reduced pressure. Further, a high frequency power source 504 is connected to the upper electrode 510 and the electrostatic chuck 10 so that a pair of electrodes having the upper electrode 510 and the electrostatic chuck 10 face each other in parallel at a predetermined interval. Yes.

In the wafer processing apparatus 500 according to the present embodiment, when a high frequency voltage is applied between the upper electrode 510 and the electrostatic chuck 10, a high frequency discharge occurs and the processing gas introduced into the processing container 501 is excited by plasma, It is activated and the processing object W is processed. An example of the processing object W is a semiconductor substrate (wafer). However, the processing object W is not limited to a semiconductor substrate (wafer), and may be, for example, a glass substrate used in a liquid crystal display device.

The high frequency power source 504 is electrically connected to the base plate 300 of the electrostatic chuck 10. As described above, a metal material such as aluminum is used for the base plate 300. That is, the base plate 300 has conductivity. As a result, the high frequency voltage is applied between the upper electrode 410 and the base plate 300.

In the wafer processing apparatus 500 of this example, the base plate 300 is electrically connected to the first support plate 210 and the second support plate 270. As a result, in the wafer processing apparatus 500, a high frequency voltage is also applied between the first support plate 210 and the upper electrode 510 and between the second support plate 270 and the upper electrode 510.

Thus, a high-frequency voltage is applied between the support plates 210 and 270 and the upper electrode 510. Thereby, compared with the case where a high frequency voltage is applied only between the base plate 300 and the upper electrode 510, the place where the high frequency voltage is applied can be brought closer to the processing object W. Thereby, for example, plasma can be generated more efficiently and at a low potential.

An apparatus having a configuration such as the wafer processing apparatus 500 is generally called a parallel plate type RIE (Reactive / Ion / Etching) apparatus, but the electrostatic chuck 10 according to the present embodiment is not limited to application to this apparatus. . For example, ECR (Electron Cyclotron Resonance) etching apparatus, dielectric coupled plasma processing apparatus, helicon wave plasma processing apparatus, plasma separation type plasma processing apparatus, surface wave plasma processing apparatus, so-called decompression processing apparatus such as plasma CVD (Chemical Vapor Deposition) Can be widely applied to. Further, the electrostatic chuck 10 according to the present embodiment can be widely applied to a substrate processing apparatus that performs processing and inspection under atmospheric pressure, such as an exposure apparatus and an inspection apparatus. However, considering the high plasma resistance of the electrostatic chuck 10 according to the present embodiment, it is preferable to apply the electrostatic chuck 10 to the plasma processing apparatus. In addition, since a well-known structure is applicable to parts other than the electrostatic chuck 10 concerning this embodiment among the structures of these apparatuses, the description is abbreviate | omitted.

FIG. 25 is a schematic cross-sectional view showing a modification of the wafer processing apparatus according to another embodiment of the present invention.
As shown in FIG. 25, the high frequency power source 504 is electrically connected only between the first support plate 210 and the upper electrode 510 and between the second support plate 270 and the upper electrode 510. Also good. Also in this case, the place where the high frequency voltage is applied can be brought close to the processing object W, and plasma can be generated efficiently.

FIG. 26 is a schematic sectional view showing a modification of the wafer processing apparatus according to another embodiment of the present invention.
As shown in FIG. 26, in this example, the high frequency power source 504 is electrically connected to the heater element 230. As described above, the high frequency voltage may be applied between the heater element 230 and the upper electrode 510. Also in this case, the place where the high frequency voltage is applied can be brought close to the processing object W, and plasma can be generated efficiently.

The high frequency power supply 504 is electrically connected to the heater element 230 via each power supply terminal 280, for example. For example, the high frequency voltage is selectively applied to a plurality of regions (for example, the first region 231 to the fourth region 234 shown in FIG. 12A) of the heater element 230. Thereby, the distribution of the high frequency voltage can be controlled.

The high frequency power source 504 may be electrically connected to the first support plate 210, the second support plate 270, and the heater element 230, for example. The high frequency voltage is applied between the first support plate 210 and the upper electrode 510, between the second support plate 270 and the upper electrode 510, and between the heater element 230 and the upper electrode 510. Also good.

The embodiment of the present invention has been described above. However, the present invention is not limited to these descriptions. As long as the features of the present invention are provided, those skilled in the art appropriately modified the design of the above-described embodiments are also included in the scope of the present invention. For example, the shape, size, material, arrangement, etc. of each element provided in the heater plates 200, 200a, 200b, etc., the installation form of the heater element 230, the first heater element 230a, the second heater element 230b, and the bypass layer 250, etc. Are not limited to those illustrated, but can be changed as appropriate.
Moreover, each element with which each embodiment mentioned above is provided can be combined as long as technically possible, and the combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

According to an aspect of the present invention, an electrostatic chuck that can satisfy temperature uniformity and temperature controllability is provided.

10, 10a ... electrostatic chuck,
100: Ceramic dielectric substrate,
101 ... 1st main surface,
102 ... the second main surface,
107 ... 1st dielectric layer,
109 ... the second dielectric layer,
111 ... electrode layer,
113 ... convex part,
115 ... groove,
200, 200a, 200b ... heater plate,
201 ... lift pin hole,
203 ... Center,
210, 210a ... first support plate,
211 ... surface,
211a ... concave portion,
211b ... convex portion,
213 ... surface,
216 ... the first support,
216a ... first support,
216b ... the second support,
216c ... third support,
216d ... fourth support,
216e ... fifth support,
216f ... sixth support part,
217a ... seventh support part,
217b ... eighth support,
217c ... ninth support part,
217d ... Tenth support part,
217e ... eleventh support,
217f ... Twelfth support part,
217 ... second support,
218 ... third support,
219 ... the fourth support,
220 ... 1st resin layer,
230, 230a, 230b ... heater elements,
231 ... first region,
231a ... first region,
231b ... second region,
231c ... third region,
231d ... fourth region,
231e ... fifth region,
231f ... sixth region,
232 ... the second region,
232a ... seventh region,
232b ... eighth region,
232c ... ninth region,
232d-tenth region,
232e ... eleventh region,
232f ... 12th area,
233 ... a third region,
234 ... fourth region,
235 ... spaced apart part,
239 ... heater electrode,
240 ... second resin layer,
241 ... hole,
250 ... bypass layer,
251 ... Bypass section,
251a ... surface,
253 ... notch,
255a, 255b, 255c, 255d, 255e, 255f, 255g, 255h ... junctions,
257 ... spaced apart part,
259 ... the center,
260 ... third resin layer,
261 ... hole,
270 ... second support plate,
271 ... surface,
271a ... recess,
271b ... convex portion,
273 ... hole,
275 ... surface,
280 ... power supply terminal,
281: Pin part,
283: Conductor part,
285 ... the support,
287 ... Junction part,
290 ... fourth resin layer,
300 ... Base plate,
301 ... Communication passage,
303 ... bottom surface,
321 ... Introduction path,
403 ... adhesive,
500 ... Wafer processing apparatus,
501 ... Processing container,
502 ... Processing gas inlet,
503 ... exhaust port,
504 ... high frequency power supply,
510 ... Upper electrode

Claims (23)

1. A first dielectric surface on which an object to be treated is placed and a second principal surface opposite to the first principal surface; a ceramic dielectric substrate;
   A base plate provided at a position away from the ceramic dielectric substrate and supporting the ceramic dielectric substrate;
   A heater plate provided between the ceramic dielectric substrate and the base plate;
   With
   The heater plate is
   A first support plate comprising a metal;
   A second support plate comprising a metal;
   A heater element that is provided between the first support plate and the second support plate and generates heat when a current flows;
   A first resin layer provided between the first support plate and the heater element;
   A second resin layer provided between the second support plate and the heater element;
   An electrostatic chuck comprising:
2. The electrostatic chuck according to claim 1, wherein the first support plate is electrically joined to the second support plate.
3. The area of the region where the first support plate is joined to the second support plate is narrower than the area of the upper surface of the first support plate and smaller than the area of the lower surface of the second support plate. The electrostatic chuck according to claim 2.
4. The area of the region where the first support plate is joined to the second support plate is smaller than the area of the difference obtained by subtracting the area of the heater element from the area of the upper surface of the first support plate. 4. The electrostatic chuck according to claim 3, wherein the electrostatic chuck is smaller than a difference area obtained by subtracting an area of the heater element from an area of a lower surface of the support plate.
5. The upper surface of the first support plate has first irregularities,
   The electrostatic chuck according to any one of claims 1 to 4, wherein a lower surface of the second support plate has second unevenness.
6. The first unevenness follows the shape of the heater element,
   The electrostatic chuck according to claim 5, wherein the second unevenness has a shape of the heater element.
7. The distance between the first concavo-convex recess and the second concavo-convex recess is greater than the distance between the first concavo-convex protrusion and the second concavo-convex protrusion. The electrostatic chuck according to claim 6, wherein the electrostatic chuck is short.
8. 8. The electrostatic chuck according to claim 5, wherein a height of the first unevenness is different from a height of the second unevenness.
9. The electrostatic chuck according to claim 8, wherein the height of the first unevenness is lower than the height of the second unevenness.
10. The electrostatic chuck according to claim 8, wherein the height of the first unevenness is higher than the height of the second unevenness.
11. The heater element has a belt-like heater electrode,
    The electrostatic chuck according to any one of claims 1 to 10, wherein the heater electrodes are provided in a plurality of regions in an independent state.
12. A plurality of the heater elements are provided,
    The electrostatic chuck according to any one of claims 1 to 11, wherein the plurality of heater elements are provided independently in different layers.
13. 12. The electrostatic chuck according to claim 1, further comprising a conductive bypass layer provided between the heater element and the second support plate.
14. 14. The electrostatic chuck according to claim 13, wherein the heater element is electrically joined to the bypass layer and electrically insulated from the first support plate and the second support plate.
15. 15. The electrostatic chuck according to claim 13, wherein a thickness of the bypass layer is thicker than a thickness of the first resin layer.
16. The electrostatic chuck according to any one of claims 13 to 15, wherein a thickness of the bypass layer is larger than a thickness of the heater element.
17. The electrostatic chuck according to any one of claims 13 to 16, wherein the bypass layer is provided between the heater element and the base plate.
18. The electrostatic chuck according to any one of claims 1 to 17, further comprising a conductive bypass layer provided between the heater element and the ceramic dielectric substrate.
19. The electrostatic chuck according to any one of claims 1 to 18, wherein an area of an upper surface of the first support plate is larger than an area of a lower surface of the second support plate.
20. The first support plate has a plurality of support portions,
    The electrostatic chuck according to any one of claims 1 to 19, wherein the plurality of support portions are provided in an independent state.
21. 21. The electrostatic chuck according to claim 1, further comprising a power supply terminal that is provided from the heater plate toward the base plate and supplies electric power to the heater plate.
22. The power supply terminal is
    A pin connected to a socket for supplying power from the outside;
    A conducting wire part thinner than the pin part;
    A support portion connected to the conductor portion;
    A joint portion connected to the support portion and joined to the heater element;
    The electrostatic chuck according to claim 21, comprising:
23. A power supply terminal provided from the heater plate toward the base plate and supplying power to the heater plate;
    The power supply terminal is
    A pin connected to a socket for supplying power from the outside;
    A conducting wire part thinner than the pin part;
    A support portion connected to the conductor portion;
    A joint connected to the support and joined to the bypass layer;
    The electrostatic chuck according to any one of claims 13 to 17, wherein the electric power is supplied to the heater element through the bypass layer.

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