Member for semiconductor manufacturing apparatus

Abstract

In the present invention, a ceramic heater, which is a member for a semiconductor manufacturing apparatus, comprises: a ceramic plate 20; a thermocouple passage 40; and a thermal spray coating 43. The thermocouple passage 40 includes: a passage hole 41, which is bored from an outer peripheral surface 20c of the ceramic plate 20 towards a thermocouple insertion port 40a provided on the centre lower surface-side of the ceramic plate 20; and an insertion member 42, which is inserted into the passage hole 41 from an opening 41a, of the passage hole 41, opening to the outer peripheral surface 20c of the ceramic plate 20. The thermal spray coating 43 closes a gap between the insertion member 42 and the passage hole 41.

Description

Semiconductor manufacturing equipment components

[0001] The present invention relates to a member for a semiconductor manufacturing device.

[0002] Semiconductor manufacturing equipment, such as etching equipment, ion implantation equipment, and electron beam exposure equipment, is used to secure wafers and heat and cool them. A known component (semiconductor manufacturing equipment component) for such semiconductor manufacturing equipment includes a disc-shaped ceramic plate having a wafer-mounting surface on its upper surface, a hollow ceramic shaft bonded to the lower surface of the ceramic plate, and a thermocouple passage extending from an inner region of the ceramic shaft on the lower surface of the ceramic plate to just before the outer periphery of the ceramic plate (see Patent Document 1). The thermocouple passage is composed of a passage hole drilled from the outer periphery of the ceramic plate toward the center, and a cap that closes the opening of the passage hole that opens to the outer periphery of the ceramic plate. The cap is made of the same material as the ceramic plate. One example of manufacturing this semiconductor manufacturing equipment component is described, in which the ceramic shaft is positioned on the lower surface of the ceramic plate, the opening of the passage hole is closed with a cap, and then these components are diffusion-bonded in a single step.

[0003] Patent No. 5501467

[0004] However, during diffusion bonding, it is difficult to press the cap radially inward (horizontally) against the opening on the outer peripheral surface of the ceramic plate, which can result in insufficient bonding of the cap and problems with the sealing of the thermocouple passage.

[0005] The present invention has been made to solve such problems, and its main object is to improve the sealing performance of the thermocouple passage.

[0006] [1] A first semiconductor manufacturing equipment member of the present invention comprises: a disc-shaped ceramic plate having a wafer mounting surface on its upper surface; a passage hole drilled from the outer circumferential surface of the ceramic plate toward a thermocouple insertion port provided on the central underside of the ceramic plate; a thermocouple passage having an insertion member inserted into the passage hole from an opening of the passage hole that opens on the outer circumferential surface of the ceramic plate; and a thermal sprayed film that seals a gap between the insertion member and the passage hole.

[0007] In this semiconductor manufacturing equipment component, the thermocouple passage includes a passage hole drilled from the outer peripheral surface of the ceramic plate toward a thermocouple insertion opening provided on the underside of the center of the ceramic plate, and an insert member inserted into the passage hole through an opening of the passage hole that opens on the outer peripheral surface of the ceramic plate. The gap between the insert member and the passage hole is sealed with a thermally sprayed film. The thermally sprayed film is formed, for example, with a thermal spray gun. This improves the sealing performance of the thermocouple passage compared to conventional methods in which an insert member is inserted into the passage hole and joined by pressing it horizontally.

[0008] In this specification, "upper" and "lower" do not represent absolute positional relationships, but rather relative positional relationships. Therefore, depending on the orientation of the semiconductor manufacturing equipment component, "upper" and "lower" may become "lower" and "upper," "left" and "right," or "front" and "rear."

[0009] [2] The first semiconductor manufacturing equipment component of the present invention (the first semiconductor manufacturing equipment component described in [1] above) may include a hollow ceramic shaft joined to the underside of the ceramic plate, the ceramic plate may be a one-piece member, and the thermocouple insertion port may be provided in an inner shaft region surrounded by the ceramic shaft on the underside of the ceramic plate. In this case, it is highly necessary to drill a passage hole from the outer peripheral surface of the ceramic plate.

[0010] [3] In the first semiconductor manufacturing equipment member of the present invention (the first semiconductor manufacturing equipment member described in [1] or [2] above), the outer end surface of the sprayed film may be provided at the same position as the outer peripheral surface of the ceramic plate or at a position recessed therefrom. In this way, for example, when the outer shape of the ceramic plate is machined using a processing machine, there is no risk of the processing machine getting caught on the sprayed film.

[0011] [4] In the first semiconductor manufacturing equipment member of the present invention (the first semiconductor manufacturing equipment member according to any one of [1] to [3] above), a tapered surface that narrows inward may be provided on the opening side of the passage hole, and the insertion member may have a surface that can come into contact with the tapered surface. This improves adhesion between the insertion member and the opening side of the passage hole.

[0012] [5] In the first semiconductor manufacturing equipment member of the present invention (the first semiconductor manufacturing equipment member according to any one of [1] to [4] above), the insert member may be threadedly engaged with the passage hole. This facilitates the work of thermal spraying to close the gap between the insert member and the passage hole.

[0013] [6] A second semiconductor manufacturing equipment member of the present invention comprises: a disc-shaped ceramic plate having a wafer mounting surface on its upper surface; a notch that appears in the ceramic plate after a portion of the boundary between the lower surface and the outer peripheral surface of the ceramic plate is cut out in a predetermined shape; a passage hole drilled from the notch toward a thermocouple insertion port provided on the central lower surface side of the ceramic plate; and a thermocouple passage having the same shape as the predetermined shape and a sealing member joined to the notch.

[0014] In this semiconductor manufacturing equipment component, a portion of the boundary between the underside and outer periphery of the ceramic plate is cut out to a predetermined shape, and then a sealing member of the same shape as the cutout appears in the ceramic plate. The sealing member can be pressed vertically to join the sealing member. This improves the sealing performance of the thermocouple passage compared to the conventional method of inserting an insertion member into the passage hole and pressing it horizontally to join the sealing member.

[0015] [7] The second semiconductor manufacturing equipment member of the present invention (the second semiconductor manufacturing equipment member described in [6] above) may include a hollow ceramic shaft joined to the underside of the ceramic plate, the ceramic plate may be a one-piece member, and the thermocouple insertion port may be provided in an inner shaft region surrounded by the ceramic shaft on the underside of the ceramic plate. In this case, it is highly necessary to drill a passage hole from the outer peripheral surface of the ceramic plate.

[0016] [8] In the second semiconductor manufacturing equipment member of the present invention (the second semiconductor manufacturing equipment member described in [6] or [7] above), the surface of the cutout portion where the passage hole opens may be an inclined surface. In this case, a sealing member can be joined to the inclined surface of the cutout portion. In this case, the predetermined shape may have a vertical cross section of a triangle (for example, a right-angled triangle).

[0017] [9] In the second semiconductor manufacturing equipment member of the present invention (the second semiconductor manufacturing equipment member described in [8] above), the angle of the inclined surface may be 5 to 30°. This makes it possible to prevent the bonding agent (paste or liquid agent used for bonding) from flowing down the inclined surface when the bonding agent is applied to the inclined surface.

[0018]

[10] In the second semiconductor manufacturing equipment member of the present invention (the second semiconductor manufacturing equipment member described in [6] or [7] above), the surface of the cutout portion into which the passage hole opens may be a vertical surface. In this case, the predetermined shape may be a quadrilateral (e.g., rectangular) shape in vertical cross section.

[0019] 1. A perspective view of the ceramic heater 10 of the first embodiment. A cross-sectional view taken along line A-A in FIG. 1. A cross-sectional view taken along line B-B in FIG. 1. An enlarged view of portion C in FIG. 2. A perspective view showing how an insertion member 42 is inserted into a passage hole 41. An explanatory diagram showing the process of forming a thermocouple passage 40, etc. A partially enlarged cross-sectional view of the ceramic plate 20 of the second embodiment. A perspective view showing how a sealing member 142 is attached to a cutout 180. An explanatory diagram showing the process of forming a thermocouple passage 140, etc. A partially enlarged cross-sectional view of a modified example of the ceramic plate 20 of the first embodiment. A partially enlarged cross-sectional view of a modified example of the ceramic plate 20 of the second embodiment. A perspective view showing how a sealing member 442 is attached to a cutout 480.

[0020] [First Embodiment] The first embodiment is an example of a first semiconductor manufacturing equipment member of the present invention. Fig. 1 is a perspective view of a ceramic heater 10, Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1 (a longitudinal cross-sectional view of the ceramic heater 10), Fig. 3 is a cross-sectional view taken along line B-B in Fig. 1, Fig. 4 is an enlarged view of portion C in Fig. 2, and Fig. 5 is a perspective view showing how an insertion member 42 is inserted into a passage hole 41. For convenience, Fig. 2 shows the positions of the power supply rods 32, 33a, 33b, 34a, and 34b shifted so as not to overlap. Fig. 5 shows the ceramic plate 20 with the upper surface 20a facing downward and the lower surface 20b facing upward.

[0021] The ceramic heater 10 includes a ceramic plate 20 , an RF electrode 22 , an inner peripheral resistance heating element 23 , an outer peripheral resistance heating element 24 , a ceramic shaft 30 , and a thermocouple passage 40 .

[0022] The ceramic plate 20 is a disk-shaped plate made of a ceramic material, such as aluminum nitride or alumina. The ceramic plate 20 is a one-piece component, rather than a component formed by stacking and bonding multiple thin plates. The upper surface 20a of the ceramic plate 20 is provided with a circular wafer mounting surface 21a, an annular flat surface 21b surrounding the wafer mounting surface 21a, and a bank 21c connecting the wafer mounting surface 21a and the annular flat surface 21b. A wafer W is mounted on the wafer mounting surface 21a. The annular flat surface 21b is one step higher than the wafer mounting surface 21a. The bank 21c is formed so as to slope downward from the annular flat surface 21b toward the wafer mounting surface 21a. The lower surface 20b of the ceramic plate 20 is provided in a portion surrounded by the ceramic shaft 30 with a recess 20e. The recess 20e is a circular groove with a diameter equal to the inner diameter of the ceramic shaft 30. The average grain size (average sintered grain size) of the ceramic plate 20 is preferably 1 to 5 μm. An RF electrode 22 , an inner peripheral resistance heating element 23 , and an outer peripheral resistance heating element 24 are embedded in the ceramic plate 20 .

[0023] The RF electrode 22 is an electrode for generating plasma above the wafer W and is, for example, a circular electrode made of a conductive mesh sheet. The RF electrode 22 is disposed parallel or substantially parallel to the wafer mounting surface 21 a. An RF electrode rod 32 is electrically connected to the RF electrode 22. The RF electrode rod 32 extends from the lower surface 20 b of the ceramic plate 20 through the interior of the ceramic shaft 30 to the outside of the ceramic shaft 30. The ceramic plate 20 is divided into a small circular inner zone Z1 and an annular outer zone Z2 by an imaginary boundary VB ( FIG. 3 ) concentric with the ceramic plate 20. An inner resistance heating element 23 is embedded in the inner zone Z1, and an outer resistance heating element 24 is embedded in the outer zone Z2. The inner and outer resistance heating elements 23, 24 are embedded below the RF electrode 22 and are disposed on the same plane parallel or substantially parallel to the wafer mounting surface 21 a. However, the inner and outer resistance heating elements 23, 24 may be provided on different planes.

[0024] As shown in FIG. 3 , the inner peripheral resistance heating element 23 is formed so that it originates from one of a pair of terminals 23a, 23b, is folded back at multiple folds in a single stroke, and is routed throughout almost the entire inner peripheral zone Z1, and then reaches the other of the pair of terminals 23a, 23b. The pair of terminals 23a, 23b is provided in the inner-shaft region 20d (a region of the lower surface 20b of the ceramic plate 20 surrounded by the ceramic shaft 30). In this embodiment, the inner-shaft region 20d is the bottom surface of the recess 20e. Metal (e.g., Ni) power supply rods 33a, 33b are joined to the pair of terminals 23a, 23b, respectively. The power supply rods 33a, 33b extend from the lower surface 20b of the ceramic plate 20 through the interior of the ceramic shaft 30 and reach the outside of the ceramic shaft 30.

[0025] As shown in FIG. 3 , the outer-periphery resistance heating element 24 extends from one of a pair of terminals 24a, 24b into the outer-periphery zone Z2 of the ceramic plate 20, is folded back at multiple folds in a single stroke to cover almost the entire outer-periphery zone Z2, and then extends from the outer-periphery zone Z2 to the other of the pair of terminals 24a, 24b. The pair of terminals 24a, 24b is provided in the inner-shaft region 20d on the lower surface 20b of the ceramic plate 20. Metal (e.g., Ni) power supply rods 34a, 34b are joined to the pair of terminals 24a, 24b, respectively. The power supply rods 34a, 34b extend from the lower surface 20b of the ceramic plate 20 through the interior of the ceramic shaft 30 to the outside of the ceramic shaft 30.

[0026] Examples of materials for the inner and outer resistance heating elements 23, 24 include W, Mo, W / Mo alloy, WC, and WC-TiN. Examples of shapes for the inner and outer resistance heating elements 23, 24 include coil, ribbon (strip), mesh, and wire. The inner and outer resistance heating elements 23, 24 may have a printed pattern.

[0027] The ceramic shaft 30 is a hollow, cylindrical member, and is joined to the lower surface 20b of the ceramic plate 20 so as to be coaxial with the ceramic plate 20. The ceramic shaft 30 is preferably formed from the same material as the ceramic plate 20. The ceramic shaft 30 is joined to the lower surface 20b of the ceramic plate 20 by a direct ceramic joining method. Examples of direct ceramic joining methods include the diffusion bonding method, as well as the method described in Japanese Patent Laid-Open No. 2004-345952 and the method described in Japanese Patent No. 2783980. The diffusion bonding method is a method in which ceramic members are heated under pressure while in direct contact with each other, causing the constituent elements to diffuse and join them. The direct ceramic joining method described in JP 2004-345952 A is a method in which a bonding agent containing aluminum nitride ceramic powder and a flux containing CaO, YO, and AlO is applied to at least one joining surface of two aluminum nitride ceramic members to be joined, and the joining surfaces of the two ceramic members are overlapped and heated under pressure.The direct ceramic joining method described in JP 2783980 A is a method in which a solution of an yttrium compound is applied to at least one joining surface of two aluminum nitride ceramic members to be joined, and the joining surfaces of the two ceramic members are overlapped and heated.

[0028] The thermocouple passage 40 is a passage for inserting an outer thermocouple 50 that measures the temperature on the outer periphery of the ceramic plate 20. As shown in FIGS. 4 and 5 , the thermocouple passage 40 has a passage hole 41 drilled from the outer periphery 20c of the ceramic plate 20 toward a thermocouple insertion port 40a provided on the central underside of the ceramic plate 20, and an insertion member 42 ( FIGS. 4 and 5 ) inserted into the passage hole 41 through an opening 41a of the passage hole 41 that opens on the outer periphery of the ceramic plate 20. The thermocouple insertion port 40a opens on a side surface of the recess 20e of the ceramic plate 20. The outer periphery thermocouple 50 is a flexible thermocouple. The temperature measuring portion 50a provided at the tip of the outer periphery thermocouple 50 is inserted from the outside of the ceramic shaft 30 through the interior of the ceramic shaft 30 into the thermocouple insertion port 40a and reaches the end of the thermocouple passage 40.

[0029] As shown in FIGS. 4 and 5 , the passage hole 41 extends linearly from the opening 41a in the radial direction of the ceramic plate 20 and parallel to the wafer mounting surface 21a. However, the passage hole 41 may be any hole that communicates the opening 41a and the thermocouple insertion port 40a. For example, the passage hole 41 may be offset from the radial direction of the ceramic plate 20 or angled with respect to the wafer mounting surface 21a. The passage hole 41 includes a narrow-diameter portion 41x, a tapered portion 41y, and a wide-diameter portion 41z. The narrow-diameter portion 41x is provided in the section from the thermocouple insertion port 40a to just before the outer peripheral surface 20c of the ceramic plate 20. The tapered portion 41y and the wide-diameter portion 41z are provided in the portion of the passage hole 41 on the opening 41a side. The wide-diameter portion 41z is provided in the section from the opening 41a to a position a predetermined distance inward (inward radially). The large-diameter portion 41z has an inner peripheral surface provided with a female screw. The tapered portion 41y is provided between the large-diameter portion 41z and the small-diameter portion 41x. The tapered portion 41y has a tapered surface whose diameter decreases from the large-diameter portion 41z toward the inside (radially inward).

[0030] As shown in FIGS. 4 and 5 , the insert member 42 includes a truncated cone portion 42y and a cylindrical portion 42z. The cylindrical portion 42z has an outer peripheral surface provided with a male thread that can be threaded with the female thread of the large-diameter portion 41z. The outer peripheral surface of the truncated cone portion 42y abuts against the tapered surface of the tapered portion 41y. The outer end surface of the insert member 42 is formed with a linear groove 42a for inserting a flathead screwdriver (not shown) for operation. The outer end surface of the insert member 42 is recessed from the outer peripheral surface 20c of the ceramic plate 20 (e.g., recessed by approximately 1 mm from the outer peripheral surface 20c) and is covered with a thermally sprayed film 43. The insert member 42 is preferably formed of the same material as the ceramic plate 20.

[0031] As shown in FIG. 4 , the sprayed film 43 is disposed to seal the gap between the cylindrical portion 42z of the insert member 42 and the large-diameter portion 41z of the passage hole 41, and to cover the outer end surface of the insert member 42. The outer end surface of the sprayed film 43 is located at the same level as or more recessed than the outer peripheral surface 20c of the ceramic plate 20. The inner end surface of the insert member 42 is provided with a temperature sensor insertion hole 42h capable of accommodating the temperature sensor 50a of the outer thermocouple 50. The temperature sensor insertion hole 42h has a truncated conical space whose diameter decreases outward from the inner end surface of the insert member 42, and a cylindrical space extending outward from the truncated conical space. The temperature sensor 50a is guided by the tapered surface of the truncated conical space and accommodated in the cylindrical space. Examples of materials for the sprayed film 43 include aluminum nitride, alumina, yttria, and tungsten carbide, but the same material as the ceramic plate 20 is preferred. Considering the adhesion between the sprayed film 43 and the outer end surface of the insert member 42, the average surface roughness Ra of the outer end surface of the insert member 42 is preferably 0.6 to 1.4 μm.

[0032] An inner circumference thermocouple 52 for measuring the temperature of the inner circumference (near the center) of the ceramic plate 20 is also disposed inside the ceramic shaft 30. The temperature measuring portion of the inner circumference thermocouple 52 is inserted into a bottomed cylindrical hole provided in the shaft inner region 20d of the ceramic plate 20, and is in contact with the ceramic plate 20.

[0033] When the ceramic plate 20 and the ceramic shaft 30 are made of aluminum nitride, it is preferable that the insert member 42 and the sprayed film 43 are also made of aluminum nitride.

[0034] Next, a method for forming the thermocouple passages 40 and the like will be described. Figure 6 is an explanatory diagram showing the process for forming the thermocouple passages 40 and the like.

[0035] First, a disc-shaped ceramic plate 20 is prepared, with the RF electrode 22, inner circumferential resistance heating element 23, and outer circumferential resistance heating element 24 embedded therein, and with a recess 20e formed in the lower surface 20b. Then, a through-hole 91 with a circular cross section is formed by machining from the outer circumferential surface 20c of the ceramic plate 20 to the side surface of the recess 20e (FIG. 6A). The diameter of the through-hole 91 is the same as the diameter of the small-diameter portion 41x.

[0036] Next, the large diameter portion 41z and the tapered portion 41y are formed by countersinking from the outer peripheral surface 20c toward the opening of the insertion hole 91, and then a female thread is formed on the inner peripheral surface of the large diameter portion 41z (FIG. 6B). This forms the passage hole 41 having the small diameter portion 41x, the tapered portion 41y, and the large diameter portion 41z.

[0037] Next, a flat-head screwdriver is inserted into the linear groove 42a of the insert member 42, which has been prepared in advance, and the insert member 42 is screwed into the large-diameter portion 41z (FIGS. 5 and 6C). As a result, the outer peripheral surface (tapered surface) of the truncated cone portion 42y of the insert member 42 comes into contact with the tapered surface of the tapered portion 41y of the passage hole 41. The outer end surface of the insert member 42 is recessed from the outer peripheral surface 20c of the ceramic plate 20. The angle of the tapered surface of the tapered portion 41y of the passage hole 41 is preferably 10 to 45°, and more preferably 15 to 30°, from the viewpoint of facilitating contact with the insert member 42.

[0038] Next, the outer peripheral surface 20c of the ceramic plate 20, excluding the large-diameter portion 41z of the passage hole 41, is covered with a mask, and a thermal spray film 43 is formed on the outer end surface of the insert member 42 using a thermal spray gun ( FIG. 6D ). At this time, the amount of thermal spray material is adjusted so that the outer end surface of the thermal spray film 43 remains recessed from the outer peripheral surface 20c of the ceramic plate 20. As a result, the minute gap between the outer peripheral surface of the insert member 42 and the inner peripheral surface of the passage hole 41 is blocked by the thermal spray film 43. The outer end surface of the insert member 42 is also covered by the thermal spray film 43. In this manner, the thermocouple passage 40 and other components are formed in the ceramic plate 20.

[0039] Next, an example of how the ceramic heater 10 is used will be described. First, the ceramic heater 10 is installed in a vacuum chamber (not shown), and a wafer W is placed on the wafer-mounting surface 21a of the ceramic heater 10. Then, the power supplied to the inner-side resistance heating element 23 is adjusted so that the temperature of the inner-side zone Z1, detected by the inner-side thermocouple 52, reaches a predetermined inner-side target temperature. At the same time, the power supplied to the outer-side resistance heating element 24 is adjusted so that the temperature of the outer-side zone Z2, detected by the outer-side thermocouple 50, reaches a predetermined outer-side target temperature. This controls the temperature of the wafer W to a desired temperature. The vacuum chamber is then set to a vacuum or reduced-pressure atmosphere. Furthermore, by applying an AC high-frequency voltage to the RF electrode 22, plasma is generated between parallel plate electrodes consisting of the RF electrode 22 and opposing horizontal electrodes (not shown) installed above the chamber. This plasma is used to perform CVD film formation or etching on the wafer W. If a DC voltage is applied to the RF electrode 22, it can be used as an electrostatic discharge (ESC) electrode.

[0040] According to the ceramic heater 10 of this embodiment described above, the gap between the insertion member 42 and the passage hole 41 is sealed by the sprayed film 43. The sprayed film 43 is formed, for example, by a thermal spray gun. Therefore, the sealing performance of the thermocouple passage 40 is improved compared to the conventional case in which the insertion member is inserted into the passage hole and pressed horizontally to join them.

[0041] Furthermore, the ceramic heater 10 includes a hollow ceramic shaft 30, the ceramic plate 20 is a one-piece member, and the thermocouple insertion port 40a is provided in the shaft inner region 20d of the lower surface 20b of the ceramic plate 20. Therefore, there is a strong need to drill the passage holes 41 from the outer peripheral surface 20c of the ceramic plate 20.

[0042] Furthermore, the outer end surface of the sprayed film 43 covering the insert member 42 is provided at the same position as or at a position recessed from the outer peripheral surface 20c of the ceramic plate 20. Therefore, for example, when the outer shape of the ceramic plate 20 is machined using a processing machine, there is no risk of the processing machine getting caught on the sprayed film 43.

[0043] Furthermore, the portion of the passage hole 41 on the opening 41a side is provided with a tapered portion 41y having a tapered surface that narrows radially inward from the outer peripheral surface 20c of the ceramic plate 20. The insert member 42 has a surface (the tapered outer peripheral surface of the truncated cone 42y) that can come into contact with the tapered surface of the tapered portion 41y. This improves the adhesion between the insert member 42 and the portion of the passage hole 41 on the opening 41a side.

[0044] The insert member 42 is screwed into the passage hole 41. This facilitates the work of thermal spraying so as to close the gap between the insert member 42 and the passage hole 41.

[0045] Furthermore, the temperature measuring part insertion hole 42h has a truncated conical space whose diameter decreases outward from the inner end face of the insertion member 42, and a cylindrical space formed outward from the truncated conical space. Therefore, the temperature measuring part 50a of the outer peripheral thermocouple 50 is guided by the tapered surface of the truncated conical space and easily stored in the cylindrical space.

[0046] Second Embodiment The second embodiment is an example of a second semiconductor manufacturing equipment component of the present invention. The second embodiment is similar to the first embodiment except for the thermocouple passage 40 and its surrounding structure. Therefore, the following describes the configurations that differ from the first embodiment. FIG. 7 is a partially enlarged cross-sectional view of the ceramic plate 20 of the second embodiment (this portion corresponds to portion C in FIG. 2 ), and FIG. 8 is a perspective view showing how the sealing member 142 is attached to the cutout portion 180. Note that in FIG. 8 , the upper surface 20 a of the ceramic plate 20 is drawn downwards, and the lower surface 20 b is drawn upwards.

[0047] The ceramic plate 20 of the second embodiment includes a cutout 180 and a thermocouple passage 140. The cutout 180 is a portion of the ceramic plate 20 that appears after a portion P ( FIG. 8 ) of the boundary between the lower surface 20 b and the outer peripheral surface 20 c of the ceramic plate 20 is cut out into a predetermined shape (here, a right-angled triangular cross section). The thermocouple passage 140 includes a passage hole 141 and a sealing member 142. The passage hole 141 is drilled from the cutout 180 toward a thermocouple insertion port 140 a provided on the central lower surface of the ceramic plate 20. The surface of the cutout 180 where the passage hole 141 opens (the surface where the opening 141 a is provided) is an inclined surface 180 a. The sealing member 142 has the same shape as the predetermined shape when the cutout 180 is formed and has an inclined surface 142 a similar to the inclined surface 180 a of the cutout 180. The inclined surface 142a of the sealing member 142 is joined to the inclined surface 180a of the cutout 180. After the sealing member 142 is joined to the cutout 180, the ceramic plate 20 has a disk-like outer shape.

[0048] The opening 141a of the passage hole 141 is closed by a sealing member 142. A temperature measuring part insertion hole 142h capable of accommodating the temperature measuring part 50a of the outer peripheral thermocouple 50 is horizontally formed in the inclined surface 142a of the sealing member 142. The diameter of the temperature measuring part insertion hole 142h is smaller than the diameter of the passage hole 141. The temperature measuring part 50a is guided by the inclined surface 142a and accommodated in the temperature measuring part insertion hole 142h.

[0049] The sealing member 142 is preferably formed from the same material as the ceramic plate 20. The sealing member 142 is preferably bonded by a direct ceramic bonding method. As described above, direct ceramic bonding methods include the diffusion bonding method, as well as the method described in Japanese Patent Application Laid-Open No. 2004-345952 and the method described in Japanese Patent No. 2783980. In order to prevent the bonding agent (paste or liquid used for bonding) from flowing off the inclined surface 180a when applied to the inclined surface 180a, the angle of the inclined surface 180a with respect to the horizontal plane is preferably 5 to 30 degrees.

[0050] When the ceramic plate 20 and the ceramic shaft 30 are made of aluminum nitride, it is preferable that the sealing member 142 also be made of aluminum nitride.

[0051] Next, a method for forming the thermocouple passages 140 and the like will be described. Figure 9 is an explanatory diagram showing the process for forming the thermocouple passages 140 and the like.

[0052] First, a disc-shaped ceramic plate 20 is prepared, in which the RF electrode 22, the inner peripheral side resistance heating element 23, and the outer peripheral side resistance heating element 24 are embedded, and a recess 20e is formed in the lower surface 20b. Then, an insertion hole 191 having a circular cross section is formed by machining from the outer peripheral surface 20c of the ceramic plate 20 to the side surface of the recess 20e (FIG. 9A).

[0053] Next, a portion P (FIG. 8) of the boundary between the lower surface 20b and the outer peripheral surface 20c of the ceramic plate 20 is cut out in a predetermined shape to form a notch 180 in the ceramic plate 20 (FIG. 9B). As a result, a passage hole 141 having an opening 141a is formed in the inclined surface 180a of the notch 180.

[0054] Next, the inclined surface 142a of the sealing member 142, which has been previously fabricated, is bonded to the inclined surface 180a of the notch 180 using a direct ceramic bonding method (FIGS. 8 and 9C). At this time, the sealing member 142 can be pressed vertically against the notch 180, thereby tightly bonding the sealing member 142 and the notch 180. In this manner, the thermocouple passage 140 and other components are formed in the ceramic plate 20. Note that the process of bonding the sealing member 142 and the notch 180 may also simultaneously bond the ceramic plate 20 and the ceramic shaft 30 using the same bonding method. This reduces the number of manufacturing steps. However, these steps may also be performed separately.

[0055] According to the second embodiment described above, when joining a sealing member 142 having the same shape as the cutout 180 that appears in the ceramic plate 20 after cutting out a portion P of the boundary between the lower surface 20b and the outer peripheral surface 20c of the ceramic plate 20 into the predetermined shape, the sealing member 142 can be joined by pressing it vertically. Therefore, compared to the conventional case in which an insert member is inserted into the passage hole and pressed horizontally to join, the sealing member 142 has improved sealing performance for the thermocouple passage 140.

[0056] Similarly to the first embodiment, the second embodiment also includes a hollow ceramic shaft 30, the ceramic plate 20 is a one-piece member, and the thermocouple insertion port 140a is provided in the shaft inner region 20d of the lower surface 20b of the ceramic plate 20. Therefore, there is a strong need to drill the passage holes 141 from the outer peripheral surface 20c of the ceramic plate 20.

[0057] Furthermore, since the surface of the cutout 180 where the passage hole 141 opens is the inclined surface 180a, the sealing member 142 can be joined to the inclined surface 180a of the cutout 180. This further improves the sealing performance of the thermocouple passage 140.

[0058] Furthermore, a temperature measuring part insertion hole 142h is formed in the inclined surface 142a of the sealing member 142. The temperature measuring part 50a of the outer peripheral thermocouple 50 is guided by the inclined surface 142a and easily accommodated in the temperature measuring part insertion hole 142h.

[0059] [Other Embodiments] It goes without saying that the present invention is not limited to the above-described embodiments, and can be embodied in various forms as long as they fall within the technical scope of the present invention.

[0060] In the first embodiment described above, a female thread is provided on the large-diameter portion 41z of the passage hole 41, and a male thread that screws into the female thread is provided on the insert member 42, but these threads may not be provided. In that case, the linear groove 42a of the insert member 42 may also not be provided. Furthermore, although the temperature sensor insertion hole 42h is provided on the inner end surface of the insert member 42, this temperature sensor insertion hole 42h may not be provided.

[0061] In the first embodiment described above, the passage hole 41 is provided with a tapered portion 41y, but the tapered portion 41y may not be provided. A specific example is shown in FIG. 10 . The thermocouple passage 340 has a passage hole 341 and an insert member 342. The passage hole 341 is drilled from the outer peripheral surface 20c of the ceramic plate 20 toward a thermocouple insertion opening 340a provided on the central underside of the ceramic plate 20. The passage hole 341 has a large-diameter portion 341z provided on the opening 341a side and a small-diameter portion 341x provided continuous with the large-diameter portion 341z. The insert member 342 is inserted into the passage hole 341 through the opening 341a of the passage hole 341 that opens to the outer peripheral surface 20c of the ceramic plate 20. The insertion member 342 has a cylindrical portion 342z having approximately the same diameter as the large-diameter portion 341z and a cylindrical portion 342x having approximately the same diameter as the small-diameter portion 341x. As in the above-described embodiment, the insertion member 342 has a temperature sensor insertion hole 42h and a linear groove 42a, and the male thread provided in the cylindrical portion 342z is threaded into the female thread provided in the large-diameter portion 341z. Note that in Figure 10, the same components as those in the first embodiment are designated by the same reference numerals.

[0062] In the second embodiment described above, the temperature measuring part insertion hole 142h is provided in the inclined surface 142a of the sealing member 142, but this temperature measuring part insertion hole 142h does not have to be provided.

[0063] In the second embodiment described above, a notch 480 and a sealing member 442 shown in FIGS. 11 and 12 may be provided instead of the notch 180 and the sealing member 142. FIG. 11 is a partially enlarged cross-sectional view (corresponding to part C in FIG. 2 ) of a modified ceramic plate 20 of the second embodiment, and FIG. 12 is a perspective view showing the sealing member 442 being attached to the notch 480. Note that in FIG. 12 , the upper surface 20a of the ceramic plate 20 is drawn downward and the lower surface 20b is drawn upward. The ceramic plate 20 includes a notch 480 and a thermocouple passage 440. The notch 480 is a portion of the ceramic plate 20 that appears after a portion P ( FIG. 12 ) of the boundary between the lower surface 20b and the outer peripheral surface 20c of the ceramic plate 20 is cut out into a predetermined shape (here, a rectangular cross section). The notch 480 has a vertical surface 480a and a ceiling surface (horizontal surface) 480b. The thermocouple passage 440 includes a passage hole 441 and a sealing member 442. The passage hole 441 is drilled from the vertical surface 480a of the cutout 480 toward the thermocouple insertion port 440a provided on the central underside of the ceramic plate 20. The passage hole 441 opens to the vertical surface 480a. The sealing member 442 has the same shape as the predetermined shape used to form the cutout 480. The sealing member 442 has a vertical surface 442a and an upper surface (horizontal surface) 442b. The vertical surface 442a is provided with a temperature sensor insertion hole 442h. The upper surface 442b of the sealing member 442 is bonded to the ceiling surface 480b of the cutout 480, and the vertical surface 442a of the sealing member 442 is bonded to the vertical surface 480a of the cutout 480. The bonding is performed using the direct ceramic bonding method described above. In particular, the upper surface 442b of the sealing member 442 and the ceiling surface 480b of the cutout portion 480 are tightly joined because they can be joined by applying pressure in the vertical direction. Although the temperature sensor insertion hole 442h is provided in the vertical surface 442a of the sealing member 442, this temperature sensor insertion hole 442h does not have to be provided.

[0064] In the first and second embodiments described above, the inner resistance heating element 23 is embedded in the inner zone Z1 of the ceramic plate 20, and the outer resistance heating element 24 is embedded in the outer zone Z2, but this is not particularly limited. For example, the ceramic plate 20 may be divided into three or more zones, and a resistance heating element may be wired to each zone. In this case, the thermocouple passages 40, 140 are used as passages for inserting a thermocouple to measure the temperature of the outermost zone.

[0065] In the first and second embodiments described above, the RF electrode 22 is embedded in the ceramic plate 20. However, instead of or in addition to this, an electrostatic electrode may be embedded. By applying a DC voltage to the electrostatic electrode, the wafer W is attracted and fixed to the wafer mounting surface 21 a.

[0066] The present invention can be used for components used in semiconductor manufacturing equipment, such as electrostatic chuck heaters, electrostatic chucks, and ceramic heaters.

[0067] 10 ceramic heater, 20 ceramic plate, 20a upper surface, 20b lower surface, 20c outer peripheral surface, 20d shaft inner region, 20e recess, 21a wafer mounting surface, 21b annular flat surface, 21c bank, 22 RF electrode, 23 inner peripheral resistance heating element, 23a, 23b terminal, 24 outer peripheral resistance heating element, 24a, 24b terminal, 30 ceramic shaft, 32 RF electrode rod, 33a, 33b power supply rod, 34a, 34b power supply rod, 40 thermocouple passage, 40a thermocouple insertion port, 41 passage hole, 41a opening, 41x narrow diameter portion, 41y tapered portion, 41z thick diameter portion, 42 insertion member, 42a straight groove, 42h temperature measuring unit insertion hole, 42y truncated cone portion, 42z Cylinder portion, 43 sprayed film, 50 outer peripheral thermocouple, 50a temperature measuring portion, 52 inner peripheral thermocouple, 91 insertion hole, 140 thermocouple passage, 140a thermocouple insertion port, 141 passage hole, 141a opening, 142 sealing member, 142a inclined surface, 142h temperature measuring portion insertion hole, 180 notch, 180a inclined surface, 191 insertion hole, 340 thermocouple passage, 340a thermocouple insertion port, 341 passage hole, 341a opening, 341x thin diameter portion, 341z thick diameter portion, 342 insertion member, 342x cylinder portion, 342z cylinder portion, 440 thermocouple passage, 442 sealing member, 442a vertical surface, 442b upper surface, 442h Temperature measuring part insertion hole, 480 notch, 480a vertical surface, 480b ceiling surface, VB virtual boundary, W wafer, Z1 inner peripheral zone, Z2 outer peripheral zone.

Claims

1. A component for semiconductor manufacturing equipment comprising: a disc-shaped ceramic plate having a wafer mounting surface on its upper surface; a thermocouple passage having a passage hole drilled from the outer periphery of the ceramic plate toward a thermocouple insertion port provided on the central underside of the ceramic plate, and an insertion member inserted into the passage hole from an opening of the passage hole that opens on the outer periphery of the ceramic plate; and a thermal sprayed film that seals the gap between the insertion member and the passage hole.

2. A component for semiconductor manufacturing equipment according to claim 1, comprising a hollow ceramic shaft joined to the underside of the ceramic plate, the ceramic plate being a one-piece member, and the thermocouple insertion port being provided in an area of ​​the underside of the ceramic plate within the shaft that is surrounded by the ceramic shaft.

3. A semiconductor manufacturing equipment member according to claim 1 or 2, wherein the outer end surface of the thermal sprayed film is provided at the same position as the outer peripheral surface of the ceramic plate or at a position recessed therefrom.

4. A semiconductor manufacturing equipment component according to claim 1 or 2, wherein a tapered surface that narrows inward is provided in the portion of the thermocouple passage on the opening side, and the insertion component has a surface that can come into contact with the tapered surface.

5. A semiconductor manufacturing equipment member according to claim 1 or 2, wherein the insertion member is threadedly engaged with the passage hole.

6. A component for semiconductor manufacturing equipment comprising: a disc-shaped ceramic plate having a wafer mounting surface on its upper surface; a notch that appears in the ceramic plate after a portion of the boundary between the lower surface and outer peripheral surface of the ceramic plate is cut out in a predetermined shape; a passage hole drilled from the notch toward a thermocouple insertion port provided on the central lower surface side of the ceramic plate; and a thermocouple passage having a sealing member of the same shape as the predetermined shape and joined to the notch.

7. A component for semiconductor manufacturing equipment according to claim 6, comprising a hollow ceramic shaft joined to the underside of the ceramic plate, the ceramic plate being a one-piece member, and the thermocouple insertion port being provided in an area of ​​the underside of the ceramic plate within the shaft that is surrounded by the ceramic shaft.

8. A semiconductor manufacturing equipment member according to claim 6 or 7, wherein the surface of the notch where the passage hole opens is an inclined surface.

9. The semiconductor manufacturing equipment member according to claim 8, wherein the angle of the inclined surface is 5 to 30 degrees.

10. A semiconductor manufacturing equipment member according to claim 6 or 7, wherein the surface of the notch where the passage hole opens is a vertical surface.

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