TW200818383A - Electrostatic chuck heater - Google Patents

Abstract

An electrostatic chuck heater including a base which is formed by: applying conductive paste containing a binder to upper and lower surfaces of an alumina sintered body to print an electrostatic electrode and heater electrode; calcining the alumina sintered body; arranging alumina powder above the electrostatic electrode and alumina powder below the heater electrode; and pressing the alumina powder and alumina sintered body in the above state for pressure sintering. The diffusion area ratio of the conductive material near the electrostatic electrode in the dielectric layer is set not more.

Description

200818383 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to an electrostatically held heater of the Coulomb type (C〇ul〇mb). [Prior Art] In the past, Coulomb type electrostatic holding heaters were sometimes used in the production of semiconductors and the like. The electrostatic holding heater is composed of a base made of ceramic, an electrostatic electrode provided inside the substrate, a heating electrode, a power supply member connected to the electrostatic electrode and the second electrode, and various peripheral members (for example, please refer to ..., Patent Document 1). Further, a substrate mounting surface on which a substrate such as a wafer is placed is formed on the upper surface of the substrate. Then, a dielectric layer is formed from a portion of the electrostatic electrode to the substrate mounting surface, and a portion from the electrostatic electrode to the heating electrode is formed with a substrate I'. A support layer is formed by a force α-hot electrode to a lower surface of the substrate. An example of a method of manufacturing a substrate constituting the electrostatic holding heater is described. The manufacturing method is such that the substrate constituting the electrostatic holding heater is placed upside down and shaped red. The female is also awkward. The general electrostatic holding heater is arranged from the upper side to the right side +* with the electric layer, the substrate layer and the support layer. However, the layer is disposed on the lowermost side, and a substrate layer is formed on the dielectric layer, = plate = forming a support layer to form a substrate, and then the substrate is placed upside down. The following § brothers show simple manufacturing procedures. I is the plate-shaped first oxide sintered body of the electric layer, and the aluminum alloy sintered body is made of (10) U-) as the substrate layer. This place ^ 巧 Μ layer of the brother 2 milk - 97 brother 1 rolled aluminum sintered body and the second alumina burn

7066-8780-PF 5 200818383 The knot is made by hot press forming. Next, the first alumina sintered body is placed upside down so that the inside of the first oxidized sintered body is on the upper side, and the upper side of the inside is formed with an electrostatic electrode. Then, a green sheet was formed on the electrostatic electrode, a heating electrode was formed on the green sheet, and a second alumina sintered body was placed on the upper side of the heating electrode. Then, the first oxidized sintered body, the green sheet, and the second oxidized sintered body are pressed by hot pressing in the vertical direction to form a matrix. Finally, the power supply member and the peripheral member are installed on the base to complete the electrostatic holding of the heater. [Problem to be Solved by the Invention] However, in the above-described conventional electrostatic holding heater, since the portions constituting the dielectric layer and the support layer are oxidized In the case where the aluminum sintered body is formed by secondary firing, the crystal particles in the oxidized sintered body tend to coarsen. Therefore, when used as a Coulomb type electrostatic holding head, the dielectric layer has a reduced volume resistivity, and although the substrate exhibits responsiveness at room temperature without problems, it has a substrate on the substrate at a high temperature. The problem of deteriorating responsiveness. Here, the purpose of the present turtle is to provide an electrostatic holding heater which is excellent in the detachment resistance of the substrate even at a high temperature. [Means to solve the problem]

In order to achieve the above object, the electrostatic holding heater of the present invention comprises a base body composed of an oxygenated 7066-8780-PF 6 200818383 aluminum alloy sintered body, an electrostatic electrode embedded in the upper side of the base body and containing a conductive material shell, and embedded in the base body. The lower side and the heating electrode containing the conductive material, the substrate is from the electrostatic layer to the dielectric layer above the substrate, the "electrostatic electrode to the substrate layer of the heat electrode, the thermal electrode from the force port to the support layer under the substrate In the composition, the conductive paste containing the binder is applied on the upper surface of the sintered body constituting the substrate layer, and the electrostatic electrode is printed, and the heating electrode is brushed under the P layer. After the calcination, the alumina sintered body is electrostatically charged. In the state in which the alumina powder is disposed on the upper side of j and the lower side of the heating electrode, the alumina powder and the alumina sintered body are pressure-molded and pressure-fired, whereby the static electricity in the dielectric layer is formed. The diffusion area ratio of the conductive material in the vicinity of the electrode is set to 0.25% or less. [Effect of the Invention] The electrostatic holding heater of the present invention has the following effects: 1) Since it is used as a dielectric layer The portion is formed by firing only the alumina powder once. Therefore, it is possible to suppress the enlargement of the crystal particles. Therefore, the dielectric layer is sufficient to maintain the volume resistivity of the two, and is used as a Coulomb type electrostatic holding heater. And improving the detachment resistance of the substrate at a high temperature. 2) The portion of the substrate as the dielectric layer is formed by press-forming the alumina powder and then press-baking it. Therefore, during the firing process In the middle, the conductive material in the electrostatic electrode has a concern of diffusing into the oxidized powder through the adhesive in the conductive paste. However, the oxidized sintered body as the substrate layer of the present invention is subjected to calcination after application of the conductive paste. The calcination is thereby performed to remove the binder in the conductive paste. Accordingly, the conductive material in the electrostatic electrode does not diffuse into the oxidized powder, which can prevent a decrease in the volume resistivity of the dielectric layer.

7066-8780-PF 7 200818383 The use of the erectile electrostatic holding heater is based on (4) fit 由于 due to the detachability of the substrate.勹Electrostatic holding heater [Embodiment] Hereinafter, an embodiment of the present invention will be described. [electrostatic holding head]

The plan view, the dry rabbit % given in Figure 2 - (f) g % called the heater ... 曰 is not a cross-sectional view of the Η line of Figure 1. According to the '"monthly implementation type of static display, including alumina burning... ·Ά, such as the base 2, the base body formed by the mouth body 3, the upper side of the electrostatic electrode:... Substrate 3 Hot electrode 7. In the present embodiment, the lower side of the base body 3 is added to the present embodiment. The description is made by holding the heater, and the electrostatic holding device of the electrode 1 is also included in the field. The static electricity of the heating electrode 1 is also suitable for the present invention.

[Substrate] X The base 3 is formed into a substantially disk shape as shown in the upper surface (surface) of the figure 3 and the surface 3 of the figure 3, and is formed by placing a wafer on a substrate such as a wafer. The dielectric layer U, the portion of the substrate electrode 9 to the substrate mounting surface 9 and the portion of the electrostatic electrode 5 to the heating electrode 7 form a coil layer 29, from the twisted electric 厣 3 + + 1 to the substrate The portion of the lower 23 is formed to support and increase the dielectric of n. S soil layer 29 and support layer 31 are formed 8 1

〇66-878〇-PF 200818383 [Electrostatic Electrode] As shown in Fig. 12, a disk-shaped electrostatic electrode 5 having a diameter smaller than that of the outer surface of the base 3 is embedded in the upper side of the base 3. This electrostatic electrode 5 contains tungsten or a carbonized crane. The electrostatic electrode 5 can be formed by printing a conductive paste containing a crane metal powder or carbide as a conductive substance. The shape of the electrostatic electrode is not limited to a circular plate, and may be formed into a mesh shape, a comb shape, a circular shape or the like. Further, in the vicinity of the electrostatic electrode 5 in the dielectric layer 11, the diffusion area ratio of the particles of the conductive material (for example, a crane or a carbonized crane) contained in the electrostatic electrode 5 to be described later is 0.25% or less. Further, as shown in FIG. 2, a receiving hole 15 extending upward from the lower surface 23 of the base 3 is formed in the center portion of the base 3, and the power supply member 2 for the electrostatic electrode is disposed in the receiving hole 15 The upper end of 2 is connected to the electrostatic electrode 5 via the connecting member 19. A voltage is applied from the electrostatic electrode power supply member 21 to the electrostatic electrode 5 via the connection member 19, and an electrostatic adsorption force (Coulomb force) is generated in the dielectric layer 11A of the base 3 so that a substrate such as a wafer is adsorbed on the substrate of the substrate 3. Mounting surface 9. Further, the upper end of the electrostatic electrode power supply member 21 may be directly connected to the electrostatic electrode 5 without passing through the connecting member 19. [Heating Electrode] The heating electrode 7 can also be obtained by coating and printing a conductive paste. The conductive adhesive contains a powder and a binder as tungsten or tungsten carbide. Further, as shown in Fig. 2, the heating electrode 7 is embedded in the lower side of the base member 3, specifically, on the lower side of the electrostatic actuator 5. Then, a receiving hole 17 extending upward from the lower φ 23 of the base 3 is formed, and the receiving hole is formed.

7066-8780-PF 9 200818383 17 is equipped with a heating electrode for the %% ΛΑ L mountain and then a thousand A. The upper electrode of the heating electrode power supply member 25 is connected to the heating electrode 7 via the connection member 27 for the electrode power supply 槿 #U . From the heating potential, the electric component 25 is applied to the twisted lightning pole 7 via the connecting member -7 ^ _ 丹 ,, the heating electrode 7 is heated and supplied with electricity A 4c I ..., the blasting surface 9 The earth plate to be placed is also connected to the heating electrode 7 by the upper end connecting member 27 of the heating electrode power supply member 25. However, the sitting is made of [electrostatic holding head manufacturing method]. The electrostatic holding heating of the present embodiment. The manufacturing procedure of the apparatus is as shown in Fig. 3. <Preparation and calcination of the alumina sintered body> First, as shown in Fig. 3(a), the substrate sound 29 made/based on the substrate 3 is sintered in the oxide body by the junction 41'. The surface of the body 41 (above) 41/coating paste 43 and 45, whereby the electrostatic electrode 5 is formed on the surface of the oxidized money body 41, and the heating electrode 7 is formed therein. The thunder of the electrostatic electrode 5 is formed. "A ,, m$a * &amp; electrogel 43, contains powder and binder of tungsten (W) or tantalum tungsten carbide (WC) as a conductive material. Therefore, the alumina sintered body 4i coated with the thunder 躜d 41 and the 骖43, 45 is subjected to satin burning so that the adhesive in the conductive cesium 43 and 45 is diffused to the outside. M-中. Calcination is carried out in a non-oxidizing environment in which an inert gas or LT temple does not emulsify a conductive material. Shell <Pressure Forming and Firing of Alumina Powder> The method of producing the oxidized (tetra) body is as follows, for example. As the Taman raw material, alumina powder of a purity (for example, ^9.7%) and magnesium oxide (Μ?), which is a k-junction aid, are used. In this ceramic raw material powder is added as

7066-8780-PF 200818383 ==Diluted alcohol (PVA), water, dispersant, etc., mixed with a rotary screen (4) (for example, 16 hours) to prepare a slurry. Here, the blending amount of the polyethylene glycol is preferably 2% by weight (wt%). The obtained spray spray was dried using a spray dryer to obtain a granulated alumina powder. 7 as shown in Fig. 3(b), the alumina powder 47 is housed in a mold (not shown) and placed on the oxygen (tetra) powder 47. The above-mentioned guide (four) 43, 45 &amp; The body 4 contains alumina powder 49 on the oxidized sintered body. In this state, the oxidized powders 47 and 49 are disposed on both sides of the alumina sintered body 41. In this state, as shown in Fig. 3(c), the oxidized powders 47 and 49 and the alumina sintered body 41 are pressurized. The p is pressurized to form oxidation, and the molded body 5 is then subjected to pressure firing in a non-oxidizing gas atmosphere. By this calcination, the oxygen fairy formed body 51 can be sintered by oxidation, and then the inside of the alumina sintered body is subjected to planar grinding processing by diamond grinding grains to adjust the thickness of the oxide (four) body. Then, the side surface of the sintered body was ground and subjected to necessary opening, thereby completing the electrostatically holding the base 3 of the heater 1. Further, in the present embodiment, the alumina powders 47 and 49 are calcined in an oxidizing atmosphere at a temperature of 450 C or higher in advance, and the binder of the oxidized uncle bodies 47 and 49 is dissipated, and then It is preferably used for a shaped body. Further, the upper limit temperature of the calcination is preferably 14 〇〇 15 15 〇 (rc. Above i5 〇 (rc, the alumina powders 47, 49 may cause agglomeration accompanying sintering, etc.). The type can obtain the following effects: 1) Since the portion which is the dielectric layer is only fired once alumina powder

7066-8780-PF 11 200818383 Formed by the body 49, the crystal particles are not enlarged. Therefore, the dielectric layer 11 can maintain a high volume resistivity and, when used as a Coulomb type electrostatic holding heater 1, the detachment resistance of the substrate when the temperature is raised. 2) The portion of the base 3 which is the dielectric layer n is formed by press-forming the alumina powder 49 and firing it. Therefore, in the firing process, the conductive substance (tungsten or tungsten carbide) in the electrostatic electrode 5 has a fear of diffusing into the alumina powder 49 via the binder in the conductive paste 43. However, since the present embodiment is applied to the oxidized sintered body 41 printed with the conductive paste, it is calcined to cause the adhesive in the conductive paste 43 to diverge and disappear. According to the following, the conductive material in the electric electrode 5 does not diffuse into the alumina powder 49, and the decrease in the volume resistivity of the dielectric layer 11 can be prevented. Further, when used as the core type electrostatic holding heater 1, the volume resistivity at a high temperature is high. Therefore, since the detachment resistance of the substrate is improved, it is very suitable for use as the electrostatic holding heater 1. 3) In the present embodiment, the base electrode 3 is provided with an electrostatic electrode 5 and a heat-adding electrode 7. This is formed in the base body 3 in the up and down direction to form a through hole for inserting a lifter pin. In this case, it is necessary to provide a separate hole in the electrostatic electrode 5 and the heating electrode 7 in correspondence with the through hole of the base 3. In accordance with the prior art, the pressure of the electrostatic electrode 5 and the heating electrode 7 is difficult because the plurality of oxidized sintered bodies or the green sheets are pressed and the substrate is molded. For example, in the case where the through holes are formed in the two electrodes 5 and 7, in order to secure the insulation distance between the through holes provided in the base 3 and the through holes provided in the electrostatic electrode 5 and the heating electrode 7, the hole positions of the two electrodes are considered.

7066-8780-PF 12 200818383 Must be set to be larger.

The positional deviation is such that the through-holes of the electrodes 5 and 7 are large, and the insulation distance between the position of the electrostatic electrode electrode 5 and the heating electrode 7 formed by the surface of the body 41 is extremely variable. Smaller, for example, the distribution of electrostatic attraction becomes more uniform, and the degree of ritual and degree enhances the soaking of the heater. 4) Conventionally, during the firing of the alumina sintered body, the conductive material (w or wc) contained in the electrostatic electrode 5 has a fear of being diffused by the binder in the alumina powder 49. In this case, the actual volume resistivity of the dielectric layer n is lowered, and the detachment resistance of the substrate is lowered. Since the dielectric layer u is thin in the case where the thickness is thin, it is necessary to make the dielectric layer 丨丨 thick. The voltage applied in the case where the dielectric layer 11 is thick must also be high, and it is difficult to control. However, according to this embodiment, since the oxidized sintered body printed with the conductive paste is subjected to calcination, the conductive paste 43 is inside. The binder dissipates into the outside air. Accordingly, since the conductive material can be prevented from diffusing into the oxide powder 49 via the binder, the volume resistivity of the dielectric layer 11 is actually increased, and the detachment resistance is improved. Moreover, by this, the dielectric layer 11 can be formed to have a thin thickness, for example, 〇 1 to 〇 2 mm, thereby reducing the applied voltage. 5) Moreover, if the alumina powders 47 and 49 are calcined in an oxidizing atmosphere at a temperature of 450 ° C or higher, the binder in the oxidized powders 4 7 and 49

7066-8780-PF 13 200818383 is dissipated, and by using the calcined alumina powder for forming, the diffusion of the conductive material in the conductive pastes 43, 45 can be more suppressed. [Examples] Next, the present invention will be specifically described using examples. [Example 1] First, as an example 1, an electrostatic electrode and a heating electrode were formed on both surfaces of an alumina sintered body, and alumina powder was disposed on both sides of the alumina sintered body, and the alumina powders were placed thereon. And the alumina sintered body is pressurized and

Burnt. The following is a detailed description with reference to Table 1. Table 1 Inventive Example 1 Inventive Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Dielectric Layer Powder Powder Sintered Body Sintered Body Powder Support Member Sintered Body + Powder Sintered Body + Powder Sintered Body + Powder Embryo Sheet + sintered body sintered body + powder electrode firing temperature 450 〇 C 1000 ° C Unfired unfired unfired dielectric layer average particle size 4 / zm 4 ^ 111 12 / im 12 / / m 4//m Dielectric layer volume resistance (Ω *cm) RT &gt;1E+17 &gt;1E+17 1E+16 1E+16 9E+16 100〇C 2E+16 8E+16 3E+14 3E+ 14 3E+15 200°C 1E+16 1E+16 1E+13 1E+13 1E+14 Insulation withstand voltage: 1_(V) 18 20 21 21 14 Average value of WC diffusion distance (//m) 150 100 280 280 280 WC diffusion area ratio (%) (section range of 850x300//m) 0.25 0.2 0.4 0.4 0.4 off response time (sec) RT &lt;1 &lt;1 &lt;1 &lt;1 &lt;1 &lt;1 100 °C &lt ;1 &lt;1 40 40 20 200°C 14 3 &gt;60 &gt;60 42 Comprehensive evaluation〇〇X x Δ 14

7066-8780-PF 200818383 <Example 1 of the present invention> First, an alumina sintered body as the substrate layer 29 was produced. The carbon content in the alumina structure is . Above (10). Further, the relative density is 98; the above 'purity is 95% or more. It is still possible to use Changqing or use hot pressing at the time of sintering. In this embodiment, hot pressing is used to manufacture an oxidized sintered body.

Next, an electrostatic electrode is printed on the surface and inside of the alumina sintered body to heat the electrode. Specifically, a slurry containing a powder of tungsten carbide (WC) and a binder is applied to both surfaces of the oxidized|g sintered body and dried. Then, the alumina sintered body coated with the slurry is calcined at a temperature of 450 C or higher in a non-oxidizing atmosphere to dissipate the binder in the charge. Then, the alumina powder is placed in the mold, and the alumina sintered body is placed on the alumina powder, and the alumina powder is accommodated from the alumina sintered body. In this state, alumina powder is used. The body and the alumina sintered body were repeatedly molded to produce an alumina molded body. Finally, the alumina shaped body was subjected to pressure baking at a temperature of 160 (rc for 2 hours) to prepare a substrate of the example of the present invention. <Example 2 of the present invention> Relative to the foregoing invention. In the present invention, the temperature of the calcination was changed to 10 〇 0 (rc, except for the calcination temperature, and was produced under the same conditions and method as in the inventive example 1. <Comparative Example 1> First, heat was used. An alumina sintered body which is a dielectric layer is formed by pressing. The carbon content of the alumina sintered body is 0.1% by weight or less, and the relative density is 98% or more and the purity is 95% or more.

7066-8780-PF 15 200818383 An electrostatic electrode is printed on the underside of the alumina sintered body. The powder containing tungsten carbide (wc) was applied to the underside of the sintered body and dried. μΑ 烕 is an alumina sintered body of the support layer. A heated electrode is formed by applying a powder of tungsten (W) and a slurry of a binder on top of the aluminum oxide k-junction.

Eight. In the case of the two alumina sintered bodies, the individual electrostatic electrodes and the heating electric, the polar ones are opposite to each other, and the alumina auxiliaries are held between the oxon oxide bodies. The powder and the alumina sintered body were press-formed to prepare an alumina molded body. Finally, the aluminum oxide molded body was fired by hot pressing (at a temperature of 160 (rc for 2 hours) to prepare a substrate of Comparative Example 1. <Comparative Example 2> Comparative Example 2 was compared with the above Comparative Example 2 The difference is that the embryo is held between the oxidized sintered bodies, and the other conditions are the same as those of Comparative Example i.

Secondly, in the above-mentioned body, it is produced by a slurry method of alumina and a binder. η <Comparative Example 3> The difference of Comparative Example 3 with respect to the above-described Example 1 of the present invention is that the engineering of applying calcination to the alumina sintered body in which the electrostatic electrode and the heating electrode are formed is omitted, and the present invention 1 Manufactured under the same conditions and methods. [Evaluation] The degree of deficiencies of the tungsten carbide particles of the second embodiment of the present invention and the comparative example 1 was compared. Fig. 4 is an electron microscope photograph (SEM photograph) of the vicinity of the boundary between the dielectric layer and the substrate layer of Example 2 of the present invention. Further, Fig. 5, 7066-8780-PF 16 200818383, is shown as an electron microscope photograph (SEM photograph) of a multiple of the dielectric layer and the substrate layer boundary of Comparative Example 1. Further, Fig. 6 is a portrait image of binarized Fig. 4, showing the degree of diffusion of tungsten carbide particles in the cross section of 300 #mx85〇vm in the dielectric layer. Fig. 7 is a view showing the image of the tungsten carbide particles in the range of 300 // mx850 /zin in the substrate layer. As shown in Figs. 6 and 7, the tungsten carbide particles of Example 2 of the present invention showed little diffusion, and it was found that the tungsten carbide particles of the comparative example had a relatively large amount of diffusion. These can be clarified by the WC diffusion area ratio shown in Table 1. The diffusion distance of WC at this point is defined by the diffusion area ratio of &amp; wc as follows. WC Diffusion Distance: The distance from the electrode to the group of tungsten carbide particles farthest from the electrode in the binary image data. WC area diffusivity: In the binary image data, the ratio of the black portion of the section of 30 0 // mx85〇// m adjacent to the electrode, the long side of the 850 // m is adjacent to the electrode . By setting the diffusion area ratio of wc to 0.25% or less, the effect of greatly shortening the response time of the substrate can be obtained even in a high temperature state. Further, as shown in Table 1, since the particle diameter of alumina in the dielectric layers of Examples 2 and 2 of the present invention was smaller than that of Comparative Examples i and 2, it was considered that the dielectric layer had a high volume resistivity. As described above, according to the present invention, the volume resistivity of the dielectric layer at a temperature of 200 ° C is high, and the detachment time of the substrate at a high temperature is shortened, and in the overall evaluation, the present invention Example 2 and 2 also gave good results far superior to Comparative Examples 1 to 3.

7066-8780-PF 17 200818383 [Example 2] In the example 2 of the present invention, the baking temperature of the aluminum oxide sintered body of the inventive example 1 of Example 1 was appropriately changed. Specifically, as shown in the following Table 2, the wc particles in the case where the calcination temperature is room temperature (that is, the baking is not performed) and 3 〇 (rc, 400 C, 450 C, and 1 000 ° C) are measured. Diffusion distance The thickness of the dielectric layer is 〇.4 mm. Moreover, the response time of the calcination temperature to the substrate of 2〇〇t is not shown in the relationship diagram of Fig. 8, and the diffusion distance of the wc particles is 2〇 to the substrate ( The response time of rc is shown in the diagram of Figure 9.

Table ------ Electrode firing temperature (°c) --------- Average value of wc diffusion distance (#m) Not 280 300 280 _ 400 200 450 150 —--- _J_000^ 100 Wc diffusion area ratio (%) (circumference i 1 of 850x300 / / m) 0.4 0.4 0.4 0. 25 J- U u 0. 2 detachment response time (sec) RT &lt;1 &lt;1 &lt;1 &lt;;1_—------&lt;1 10(TC 20 21 19 &lt;1 &lt; 1 200°C 42 43 41 14 r\ — 3 --^ L矸价” As shown in Figure 8, 9 and Table 2, it was found that by setting the firing temperature of the static electrode to 450 to 1 ,, the expansion ratio of the tungsten carbide particles is small, and the time of leaving the substrate can be shortened. What can be understood from the examples, it is found that, according to the present words, it is possible to provide the static electricity of the host even in the high-temperature substrate.

7066-8780-PF 18 200818383 Hold the heater. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view showing an electrostatic holding heater of an embodiment of the present invention. Fig. 2 is a cross-sectional view taken along line a-A of Fig. 1. Fig. 3 is a cross-sectional view showing the substrate manufacturing process of the electrostatic holding head of the present embodiment, wherein (a) is a cross-sectional view of the conductive paste applied to both sides of the alumina sintered body, and (b) is an alumina sintered body. A cross-sectional view of the alumina powder is disposed on both sides, and (c) is a cross-sectional view of pressing and firing the alumina sintered body and the alumina powder. Fig. 4 is a photomicrograph (SEM photograph) showing a magnification of 150 times in the vicinity of the boundary between the dielectric layer and the substrate layer of Example 2 of the present invention. Fig. 5 is a photomicrograph (SEM photograph) showing a magnification of 150 times in the vicinity of the boundary between the dielectric layer and the substrate layer of the comparative example. _ Figure 6 is an image of the image of the ternary of Figure 4, showing the degree of diffusion of tungsten carbide particles in the dielectric range of 300 # mx850 μm. Fig. 7 is a view showing the image of the tungsten carbide particles in the cross section of the substrate layer in the range of 300 / zm x 850 # m in the substrate layer. Figure 8 shows the calcination temperature and 2 〇 of the substrate. A diagram of the response time of the sputum. Fig. 9 is a graph showing the relationship between the diffusion distance of WC particles and the off-response time of 2 〇〇〇c of the substrate.

7066-8780-PF 19 200818383 [Explanation of main component symbols] I : Electrostatic holding heater 3 : Substrate 5 : Electrostatic electrode 7 : Heating electrode 9 · Base mounting surface (upper substrate) II : Dielectric layer: 15 : Containment Hole 17 : accommodating hole 1 9 : connection member 21 : electrostatic electrode power supply member 23 : lower surface (underside of substrate) 2 5 : heating electrode power supply member 27 : connection member 29 : substrate layer 31 : support layer 41 : alumina sintered body 43 : Conductive adhesive 45 : Conductive adhesive 47 : Alumina powder 49 : Alumina powder 51 : Oxidized molded body P : Pressure 20

7066-8780-PF

Claims (1)

200818383 X. Patent application scope: 1_ An electrostatic holding heater comprising a base body composed of an alumina sintered body, an electrostatic electrode embedded in an upper portion of the base body and containing a conductive substance, and a heating material containing a conductive substance buried on a lower side of the base body The electrode is composed of a dielectric layer from the electrostatic electrode to the upper surface of the substrate, a substrate layer from the electrostatic electrode to the heating electrode, and a support layer from the heating electrode to the lower surface of the substrate. Applying a conductive paste containing a binder to the upper surface of the alumina sintered body constituting the substrate layer, printing an electrostatic electrode, and applying a conductive paste containing a binder to the surface of the alumina sintered body, and printing a heating electrode. After the calcination of the alumina burning body, the state τ of the oxidized powder is disposed on the upper side of the electrostatic electrode and the lower side of the electrode; the oxidized powder and the oxidized sintered body are pressurized. The molding and press-baking are performed, whereby the diffusion area ratio of the conductive material in the vicinity of the electrostatic electrode in the dielectric layer is 0.25% or less. X &amp; 2. If you apply for a patent scope! The electrostatic holding heater according to the above item, wherein the alumina sintered body constituting the substrate layer is directly 185 Å or more. The degree of the dish is set to 3. As in the first application of the patent range, the enthalpy in the aforementioned electrostatic electrode. The foregoing conductive material is a tungsten metal or a device. 4. The above-mentioned conductive material of the above-mentioned heating electrode in the above-mentioned heating electrode is a crane metal or carbon 7066-8780-PF 21 200818383. 7066-8780-PF