JP2020075834A

JP2020075834A - Joined body

Info

Publication number: JP2020075834A
Application number: JP2018210191A
Authority: JP
Inventors: 吉本　修; Osamu Yoshimoto; 修吉本; 朋来村田; Tomoki Murata; 智雄田中; Tomoo Tanaka
Original assignee: NGK Spark Plug Co Ltd
Current assignee: Niterra Co Ltd
Priority date: 2018-11-08
Filing date: 2018-11-08
Publication date: 2020-05-21
Anticipated expiration: 2038-11-08
Also published as: JP7278058B2

Abstract

To suppress the progress of crack in a joining portion body while improving stress relaxation in the joining portion.SOLUTION: The joined body includes a first member, a second member formed of a material having a coefficient of thermal expansion different from that of the material of the first member, and a joining portion for joining the first member and the second member. The joining portion is formed of a plurality of porous parts having higher porosity than the first member and the second member, and there is a gap between at least two porous parts of the plurality of porous parts. The gap has no continuous material for forming the joining portion over the entire length of the joining portion in the first direction, and the opening area in at least one cross section substantially perpendicular to the first direction is larger than the opening area of the pores of the porous part.SELECTED DRAWING: Figure 4

Description

本明細書に開示される技術は、セラミックスにより形成された第１の部材と第２の部材とが接合部を介して接合された接合体に関する。 The technique disclosed in the present specification relates to a joined body in which a first member and a second member formed of ceramics are joined via a joining portion.

例えば半導体製造装置の真空チャンバー内でウェハを保持する保持装置として、静電チャックが用いられる。静電チャックは、例えばセラミックス製の板状部材と、例えば金属製のベース部材と、板状部材とベース部材とを接合する接合部と、板状部材の内部に設けられたチャック電極とを備えており、チャック電極に電圧が印加されることにより発生する静電引力を利用して、板状部材の表面（吸着面）にウェハを吸着して保持する。接合部は、シリコーン樹脂を含有する緻密体により形成されている（例えば、特許文献１参照）。 For example, an electrostatic chuck is used as a holding device that holds a wafer in a vacuum chamber of a semiconductor manufacturing apparatus. The electrostatic chuck includes, for example, a plate member made of ceramics, a base member made of metal, a joint for joining the plate member and the base member, and a chuck electrode provided inside the plate member. The electrostatic attraction generated by applying a voltage to the chuck electrode is used to attract and hold the wafer on the surface (adsorption surface) of the plate member. The joint portion is formed of a dense body containing a silicone resin (see, for example, Patent Document 1).

特開平２０１４−２０７３７４号公報JP, 2014-207374, A

ところで、接合部が多孔質体により形成された構成では、接合部が緻密体により形成された構成に比べて、板状部材とベース部材との熱膨張差による応力を緩和する応力緩和性を向上させることができる。しかし、接合部が多孔質体により形成された構成であっても、静電チャックが使用環境において熱サイクルに晒されることによって生じる熱応力によって接合部にクラックが発生し、そのクラックが接合部内において進展（伝播）することによって接合部が剥離したり破損したりするおそれがある。 By the way, in the structure in which the joint portion is formed of the porous body, the stress relaxation property for relaxing the stress due to the difference in thermal expansion between the plate-shaped member and the base member is improved as compared with the structure in which the joint portion is formed of the dense body. Can be made However, even if the joint is formed of a porous body, a crack is generated in the joint due to the thermal stress generated by the electrostatic chuck being exposed to the thermal cycle in the use environment, and the crack is generated in the joint. The progress (propagation) may cause peeling or damage to the joint.

なお、このような課題は、静電引力を利用してウェハを保持する静電チャックに限らず、セラミックスにより形成された第１の部材と、第２の部材と、多孔質体により形成された接合部とを備える接合体一般に共通の課題である。 It should be noted that such a problem is not limited to an electrostatic chuck that holds a wafer by using electrostatic attraction, and is formed by a first member made of ceramics, a second member, and a porous body. A joint body including a joint is a common problem in general.

本明細書では、上述した課題を解決することが可能な技術を開示する。 This specification discloses a technique capable of solving the above-mentioned problems.

本明細書に開示される技術は、例えば、以下の形態として実現することが可能である。 The technology disclosed in the present specification can be implemented, for example, in the following modes.

（１）本明細書に開示される接合体は、第１の方向に略垂直な第１の表面を有する第１の部材と、第２の表面を有し、前記第２の表面が前記第１の部材の前記第１の表面側に位置するように配置され、前記第１の部材の材料の熱膨張率とは異なる熱膨張率を有する材料により形成された第２の部材と、前記第１の部材の前記第１の表面と前記第２の部材の前記第２の表面との間に配置されて前記第１の部材と前記第２の部材とを接合する接合部と、を備える接合体において、前記接合部は、前記第１の部材および前記第２の部材より気孔率が高い複数の多孔質部によって形成されており、かつ、前記複数の多孔質部の少なくとも２つの多孔質部の間には、隙間が存在しており、前記隙間は、前記接合部の前記第１の方向の全長にわたって前記接合部の形成材料が連続的に存在せず、かつ、前記第１の方向に略垂直な少なくとも１つの断面における開口面積が前記多孔質部の気孔の開口面積より大きい。 (1) The joined body disclosed in the present specification has a first member having a first surface substantially perpendicular to a first direction and a second surface, and the second surface is the first member. A second member which is arranged so as to be located on the first surface side of the first member and which is formed of a material having a coefficient of thermal expansion different from that of the material of the first member; A joining part, which is arranged between the first surface of the first member and the second surface of the second member and joins the first member and the second member. In the body, the joint part is formed by a plurality of porous parts having a higher porosity than the first member and the second member, and at least two porous parts of the plurality of porous parts. There is a gap between the gaps, and the gap does not continuously exist in the material forming the joint over the entire length of the joint in the first direction, and the gap is formed in the first direction. The opening area in at least one cross section that is substantially vertical is larger than the opening area of the pores of the porous portion.

本接合体では、接合部は、第１の部材および第２の部材より気孔率が高い複数の多孔質部によって形成されている。このため、本接合体では、接合部が緻密体によって形成された構成に比べて、第１の部材と第２の部材との熱膨張差による応力を緩和する応力緩和性が向上する。また、本接合体では、多孔質部間には、隙間が存在している。隙間は、接合部の第１の方向の全長にわたって接合部の形成材料が連続的に存在せず、かつ、第１の方向に略垂直な少なくとも１つの断面における開口面積が多孔質部の気孔の開口面積より大きい空間である。このため、本接合体では、接合部に発生したクラックの進展は、接合部に形成された隙間によって遮断される。以上により、本接合体によれば、接合部に隙間が存在しない構成に比べて、接合部における応力緩和性を向上させつつ、接合部におけるクラックの進展を抑制することができる。 In the present joined body, the joined portion is formed by a plurality of porous portions having a higher porosity than the first member and the second member. Therefore, in the present joined body, the stress relaxation property for relaxing the stress due to the difference in thermal expansion between the first member and the second member is improved as compared with the structure in which the joined portion is formed of the dense body. Moreover, in this joined body, a gap exists between the porous portions. The gap is such that the material forming the joint does not continuously exist over the entire length of the joint in the first direction, and the opening area of at least one cross section substantially perpendicular to the first direction is the pore of the porous portion. It is a space larger than the opening area. Therefore, in the present joined body, the progress of the crack generated in the joined portion is blocked by the gap formed in the joined portion. As described above, according to the present joined body, it is possible to suppress the progress of cracks in the joined portion while improving the stress relaxation property in the joined portion, as compared with the configuration in which there is no gap in the joined portion.

（２）上記接合体において、前記第１の部材の前記第１の表面と前記第２の部材の前記第２の表面とで面積が小さい方の対象表面のうち、前記第１の方向視で前記隙間と重なる重複領域の総面積は、前記対象表面の面積の０．５％以上である構成としてもよい。本接合体では、第１の部材の第１の表面と第２の部材の第２の表面とで面積が小さい方の対象表面のうち、第１の方向視で隙間と重なる重複領域の総面積は、対象表面の面積の０．５％以上である（以下、対象表面の面積に対する重複領域の総面積の割合を「隙間面積割合」という）。これにより、本接合体によれば、隙間面積割合が０．５％未満である構成に比べて、接合部におけるクラックの進展を、より効果的に抑制することができる。 (2) In the joined body, in the first direction view, of the target surfaces having a smaller area between the first surface of the first member and the second surface of the second member. The total area of the overlapping region overlapping the gap may be 0.5% or more of the area of the target surface. In the present joined body, the total area of the overlapping region that overlaps with the gap in the first direction, of the target surfaces of which the area is smaller between the first surface of the first member and the second surface of the second member. Is 0.5% or more of the area of the target surface (hereinafter, the ratio of the total area of the overlapping region to the area of the target surface is referred to as “gap area ratio”). As a result, according to the present joined body, it is possible to more effectively suppress the development of cracks in the joined portion, as compared with the configuration in which the gap area ratio is less than 0.5%.

（３）上記接合体において、前記第１の部材の前記第１の表面と前記第２の部材の前記第２の表面とで面積が小さい方の対象表面のうち、前記第１の方向視で前記隙間と重なる重複領域の総面積は、前記対象表面の面積の５０％以下である構成としてもよい。本接合体によれば、隙間面積割合が５０％より高い構成に比べて、第１の部材と第２の部材との接合部による接合強度の低下を、より効果的に抑制することができる。 (3) In the joined body, in the first direction view, of the target surfaces of which the area is smaller between the first surface of the first member and the second surface of the second member. The total area of the overlapping area overlapping the gap may be 50% or less of the area of the target surface. According to the present joined body, it is possible to more effectively suppress the decrease in the joining strength due to the joining portion between the first member and the second member, as compared with the configuration in which the gap area ratio is higher than 50%.

（４）上記接合体において、前記少なくとも１つの断面において、前記複数の多孔質部のうち、少なくとも２つの多孔質部同士は、前記多孔質部より幅が狭い接続部分を介して結合している構成としてもよい。本接合体では、多孔質部同士が接続部分（くびれ）を介して結合されている。これにより、本接合体によれば、多孔質部同士の隙間を確保しつつ、多孔質部同士が結合されていない構成に比べて、多孔質部同士が補強し合うことにより接合部全体として強度を向上させることができる。 (4) In the above joined body, in the at least one cross section, at least two porous portions of the plurality of porous portions are connected to each other via a connecting portion having a width narrower than that of the porous portion. It may be configured. In the present joined body, the porous parts are connected to each other through the connecting part (constriction). Thus, according to the present joined body, the strength of the entire joined portion is enhanced by the mutual reinforcement of the porous portions as compared with the configuration in which the porous portions are not bonded while securing the gap between the porous portions. Can be improved.

（５）上記接合体において、少なくとも１つの前記隙間は、前記少なくとも１つの断面において、全周にわたって前記多孔質部に囲まれている構成としてもよい。本接合体では、接合部に存在する少なくとも１つの隙間は、少なくとも１つの断面において、全周にわたって多孔質部に囲まれている。これにより、本接合体によれば、隙間の一部が接合部の外周面まで連続的につながっている構成に比べて、隙間周囲の強度低下を抑制することができる。 (5) In the above joined body, at least one of the gaps may be surrounded by the porous portion over the entire circumference in the at least one cross section. In the present joined body, at least one gap existing in the joined portion is surrounded by the porous portion over the entire circumference in at least one cross section. As a result, according to the present joined body, it is possible to suppress a decrease in strength around the gap as compared with a configuration in which a part of the gap is continuously connected to the outer peripheral surface of the joint.

（６）上記接合体において、前記少なくとも１つの断面において、少なくとも互いに隣り合う１組の多孔質部について、前記１組の多孔質部のそれぞれの外接円の中心間距離は、前記外接円の半径の２倍以下である構成としてもよい。本接合体では、少なくとも１つの断面において、少なくとも互いに隣り合う１組の多孔質部について、１組の多孔質部のそれぞれの外接円の中心間距離は、外接円の半径の２倍以下である。これにより、本接合体によれば、１組の多孔質部のそれぞれの外接円の中心間距離が外接円の半径の２倍より長い構成に比べて、隙間の存在に起因して接合部による強度が低下することを抑制することができる。 (6) In the above joined body, in at least one cross section, at least for one set of porous parts adjacent to each other, the center-to-center distance of each circumscribed circle of each of the one set of porous parts is the radius of the circumscribed circle. It may be configured to be twice or less. In this joined body, the center-to-center distance of each circumscribed circle of one set of porous portions is at least twice the radius of the circumscribed circle in at least one cross section in at least one cross section. .. As a result, according to the present joined body, the distance between the centers of the circumscribing circles of the set of porous portions is longer than twice the radius of the circumscribing circle, and therefore, due to the existence of the gap, It is possible to prevent the strength from decreasing.

（７）上記接合体において、前記少なくとも１つの断面において、少なくとも互いに隣り合う１組の多孔質部について、前記１組の多孔質部のそれぞれの外接円の中心間距離は、前記外接円の半径の１．５倍以上である構成としてもよい。本接合体では、少なくとも１つの断面において、少なくとも互いに隣り合う１組の多孔質部について、１組の多孔質部のそれぞれの外接円の中心間距離は、外接円の半径の１．５倍以上である。これにより、本接合体によれば、１組の多孔質部のそれぞれの外接円の中心間距離が外接円の半径の１．５倍より短い構成に比べて、接合部に生じるクラックの進展を、より確実に抑制することができる。 (7) In the above joined body, in at least one cross section, at least for one set of porous parts adjacent to each other, the center-to-center distance between the respective circumscribed circles of the one set of porous parts is the radius of the circumscribed circle. It may be configured to be 1.5 times or more. In the present joined body, the center-to-center distance of each circumscribed circle of at least one set of porous parts adjacent to each other in at least one cross section is 1.5 times or more the radius of the circumscribed circle. Is. As a result, according to the present joined body, compared with a configuration in which the center-to-center distance of each circumscribing circle of one set of porous portions is shorter than 1.5 times the radius of the circumscribing circle, the cracks that develop in the joining portion are more likely to develop. Can be suppressed more reliably.

（８）上記接合体において、前記第１の部材は、セラミックスにより形成されているセラミックス部材であり、前記第２の部材は、金属により形成されているベース部材であり、前記接合体は、静電チャックである構成としてもよい。 (8) In the above joined body, the first member is a ceramic member formed of ceramics, the second member is a base member formed of metal, and the joined body is a static member. It may be configured as an electric chuck.

なお、本明細書に開示される技術は、種々の形態で実現することが可能であり、例えば、接合体、半導体製造装置用部品、保持装置、静電チャック、真空チャック、加熱装置、それらの製造方法等の形態で実現することが可能である。 The technology disclosed in the present specification can be implemented in various forms, for example, a bonded body, a semiconductor manufacturing device component, a holding device, an electrostatic chuck, a vacuum chuck, a heating device, and the like. It can be realized in the form of a manufacturing method or the like.

実施形態における静電チャック１００の外観構成を概略的に示す斜視図である。It is a perspective view which shows roughly the external appearance structure of the electrostatic chuck 100 in embodiment. 実施形態における静電チャック１００のＸＺ断面構成を概略的に示す説明図である。It is explanatory drawing which shows roughly the XZ cross-section structure of the electrostatic chuck 100 in embodiment. 本実施形態における静電チャック１００のＸＹ断面構成を概略的に示す説明図である。It is explanatory drawing which shows roughly the XY cross-section structure of the electrostatic chuck 100 in this embodiment. ベース部材２０の上面Ｓ３上に塗布された接合部前駆体３１のＸＹ平面上の配置構成を示す説明図である。6 is an explanatory diagram showing an arrangement configuration on a XY plane of a bonding portion precursor 31 applied on the upper surface S3 of the base member 20. FIG. 第１のグループの各サンプルにおける接合部による接合強度とクラック抑制とに関する評価結果を示す説明図である。It is explanatory drawing which shows the evaluation result regarding the joint strength and the crack suppression by the joint part in each sample of a 1st group. 第２のグループの各サンプルにおける接合部による接合強度とクラック抑制とに関する評価結果を示す説明図である。It is explanatory drawing which shows the evaluation result regarding the joint strength and the crack suppression by the joint part in each sample of a 2nd group.

Ａ．実施形態：
Ａ−１．静電チャック１００の構成：
図１は、本実施形態における静電チャック１００の外観構成を概略的に示す斜視図であり、図２は、本実施形態における静電チャック１００のＸＺ断面構成を概略的に示す説明図である。図２には、後述の図３のＩＩ−ＩＩの位置における静電チャック１００のＸＺ断面構成が示されている。各図には、方向を特定するための互いに直交するＸＹＺ軸が示されている。本明細書では、便宜的に、Ｚ軸正方向を上方向といい、Ｚ軸負方向を下方向というものとするが、静電チャック１００は実際にはそのような向きとは異なる向きで設置されてもよい。 A. Embodiment:
A-1. Structure of the electrostatic chuck 100:
FIG. 1 is a perspective view schematically showing an external configuration of the electrostatic chuck 100 in the present embodiment, and FIG. 2 is an explanatory diagram schematically showing an XZ sectional configuration of the electrostatic chuck 100 in the present embodiment. .. FIG. 2 shows an XZ sectional configuration of the electrostatic chuck 100 at a position II-II in FIG. 3 described later. In each drawing, XYZ axes which are orthogonal to each other for specifying the directions are shown. In the present specification, for convenience, the Z-axis positive direction is referred to as the upward direction and the Z-axis negative direction is referred to as the downward direction, but the electrostatic chuck 100 is actually installed in a direction different from such an orientation. May be done.

静電チャック１００は、対象物（例えば半導体ウェハＷ）を静電引力により吸着して保持する装置であり、例えば半導体製造装置の真空チャンバー内でウェハＷを固定するために使用される。静電チャック１００は、所定の配列方向（本実施形態では上下方向（Ｚ軸方向））に並べて配置された板状部材１０およびベース部材２０を備える。板状部材１０とベース部材２０とは、板状部材１０の下面Ｓ２（正確には、後述するメタライズ層６０の下面Ｓ５図２参照）とベース部材２０の上面Ｓ３とが、後述する接合部３０を挟んで上記配列方向に対向するように配置される。すなわち、ベース部材２０は、ベース部材２０の上面Ｓ３が板状部材１０の下面Ｓ２（メタライズ層６０の下面Ｓ５）側に位置するように配置される。 The electrostatic chuck 100 is a device that adsorbs and holds an object (for example, a semiconductor wafer W) by electrostatic attraction, and is used for fixing the wafer W in a vacuum chamber of a semiconductor manufacturing apparatus, for example. The electrostatic chuck 100 includes a plate-shaped member 10 and a base member 20 that are arranged side by side in a predetermined array direction (the vertical direction (Z-axis direction in this embodiment)). The plate-shaped member 10 and the base member 20 have a lower surface S2 of the plate-shaped member 10 (to be precise, a lower surface S5 of the metallization layer 60 described later (see FIG. 2)) and an upper surface S3 of the base member 20 which are bonded to each other at a bonding portion 30 described later. Are arranged so as to face each other in the above-mentioned arrangement direction. That is, the base member 20 is arranged such that the upper surface S3 of the base member 20 is located on the lower surface S2 (lower surface S5 of the metallized layer 60) side of the plate member 10.

板状部材１０は、上述した配列方向（Ｚ軸方向）に略直交する略円形平面状の上面（以下、「吸着面」という）Ｓ１を有する部材であり、例えばセラミックス（例えば、アルミナや窒化アルミニウム等）により形成されている。板状部材１０の直径は例えば５０ｍｍ〜５００ｍｍ程度（通常は２００ｍｍ〜３５０ｍｍ程度）であり、板状部材１０の厚さは例えば１ｍｍ〜１０ｍｍ程度である。板状部材１０は、特許請求の範囲における第１の部材に相当し、板状部材１０の下面Ｓ２は、特許請求の範囲における第１の表面に相当し、Ｚ軸方向は、特許請求の範囲における第１の方向に相当する。また、本明細書では、Ｚ軸方向に直交する方向を「面方向」という。 The plate-shaped member 10 is a member having a substantially circular planar upper surface (hereinafter, referred to as “adsorption surface”) S1 that is substantially orthogonal to the above-described arrangement direction (Z-axis direction), and is, for example, ceramics (for example, alumina or aluminum nitride). Etc.). The plate member 10 has a diameter of, for example, about 50 mm to 500 mm (usually about 200 mm to 350 mm), and the plate member 10 has a thickness of, for example, about 1 mm to 10 mm. The plate-shaped member 10 corresponds to the first member in the claims, the lower surface S2 of the plate-shaped member 10 corresponds to the first surface in the claims, and the Z-axis direction corresponds to the claims. Corresponds to the first direction in. Moreover, in this specification, a direction orthogonal to the Z-axis direction is referred to as a “plane direction”.

図２に示すように、板状部材１０の内部には、導電性材料（例えば、タングステン、モリブデン、白金等）により形成されたチャック電極４０が配置されている。Ｚ軸方向視でのチャック電極４０の形状は、例えば略円形である。チャック電極４０に電源（図示せず）から電圧が印加されると、静電引力が発生し、この静電引力によってウェハＷが板状部材１０の吸着面Ｓ１に吸着固定される。 As shown in FIG. 2, inside the plate-shaped member 10, a chuck electrode 40 formed of a conductive material (for example, tungsten, molybdenum, platinum, etc.) is arranged. The shape of the chuck electrode 40 as viewed in the Z-axis direction is, for example, a substantially circular shape. When a voltage is applied to the chuck electrode 40 from a power source (not shown), electrostatic attraction is generated, and the electrostatic attraction causes the wafer W to be attracted and fixed to the attraction surface S1 of the plate-shaped member 10.

板状部材１０の内部には、また、導電性材料（例えば、タングステン、モリブデン、白金等）を含む抵抗発熱体により構成されたヒータ電極５０が配置されている。ヒータ電極５０に電源（図示せず）から電圧が印加されると、ヒータ電極５０が発熱することによって板状部材１０が温められ、板状部材１０の吸着面Ｓ１に保持されたウェハＷが温められる。これにより、ウェハＷの温度分布の制御が実現される。 Inside the plate member 10, a heater electrode 50 composed of a resistance heating element containing a conductive material (for example, tungsten, molybdenum, platinum, etc.) is also arranged. When a voltage is applied to the heater electrode 50 from a power source (not shown), the heater electrode 50 generates heat to heat the plate-shaped member 10, and thus the wafer W held on the suction surface S1 of the plate-shaped member 10 is heated. Be done. Thereby, control of the temperature distribution of the wafer W is realized.

ベース部材２０は、例えば板状部材１０と同径の、または、板状部材１０より径が大きい円形平面の板状部材であり、例えば金属（アルミニウム、アルミニウム合金、チタン合金、鉄や銅等）により形成されている。ベース部材２０の熱膨張係数（熱膨張率）は、板状部材１０の熱膨張係数とは異なる。例えば、ベース部材２０は、金属により形成され、板状部材１０は、セラミックスにより形成されている。この場合には、ベース部材２０の熱膨張係数は、板状部材１０の熱膨張係数より大きい。ベース部材２０の直径は例えば２２０ｍｍ〜５５０ｍｍ程度（通常は２２０ｍｍ〜３５０ｍｍ）であり、ベース部材２０の厚さは例えば２０ｍｍ〜４０ｍｍ程度である。ベース部材２０は、特許請求の範囲における第２の部材に相当し、ベース部材２０の上面Ｓ３は、特許請求の範囲における第２の表面に相当する。 The base member 20 is, for example, a circular flat plate member having the same diameter as the plate member 10 or a diameter larger than that of the plate member 10, and is, for example, a metal (aluminum, aluminum alloy, titanium alloy, iron, copper, or the like). It is formed by. The coefficient of thermal expansion (coefficient of thermal expansion) of the base member 20 is different from the coefficient of thermal expansion of the plate member 10. For example, the base member 20 is made of metal, and the plate-shaped member 10 is made of ceramics. In this case, the coefficient of thermal expansion of the base member 20 is larger than that of the plate member 10. The diameter of the base member 20 is, for example, about 220 mm to 550 mm (normally 220 mm to 350 mm), and the thickness of the base member 20 is, for example, about 20 mm to 40 mm. The base member 20 corresponds to the second member in the claims, and the upper surface S3 of the base member 20 corresponds to the second surface in the claims.

ベース部材２０は、板状部材１０の下面Ｓ２とベース部材２０の上面Ｓ３との間に配置された接合部３０によって、板状部材１０に接合されている。接合部３０の厚さは、例えば１０μｍ以上、７０μｍ以下である。板状部材１０とベース部材２０とを接合するための構成については、後に詳述する。 The base member 20 is joined to the plate member 10 by the joining portion 30 arranged between the lower surface S2 of the plate member 10 and the upper surface S3 of the base member 20. The thickness of the bonding portion 30 is, for example, 10 μm or more and 70 μm or less. The configuration for joining the plate member 10 and the base member 20 will be described in detail later.

ベース部材２０の内部には冷媒流路２１が形成されている。冷媒流路２１に冷媒（例えば、フッ素系不活性液体や水等）が流されると、ベース部材２０が冷却され、接合部３０を介したベース部材２０と板状部材１０との間の伝熱（熱引き）により板状部材１０が冷却され、板状部材１０の吸着面Ｓ１に保持されたウェハＷが冷却される。これにより、ウェハＷの温度分布の制御が実現される。 A coolant passage 21 is formed inside the base member 20. When a coolant (for example, a fluorine-based inert liquid, water, or the like) is flown through the coolant channel 21, the base member 20 is cooled, and heat is transferred between the base member 20 and the plate-shaped member 10 via the joint portion 30. The plate member 10 is cooled by (heat extraction), and the wafer W held on the suction surface S1 of the plate member 10 is cooled. Thereby, control of the temperature distribution of the wafer W is realized.

また、図２に示すように、静電チャック１００には、ベース部材２０の下面Ｓ４から板状部材１０の吸着面Ｓ１にわたって上下方向に延びるピン挿通孔１４０が形成されている。すなわち、ピン挿通孔１４０は、ベース部材２０をＺ軸方向に貫通する孔２６と、接合部３０をＺ軸方向に貫通する孔３６と、板状部材１０と後述するメタライズ層６０とをＺ軸方向に貫通する孔１６とが互いに連通した一体の孔である。ピン挿通孔１４０は、板状部材１０の吸着面Ｓ１上に保持されたウェハＷを押し上げて吸着面Ｓ１から離間させるためのリフトピン（図示せず）を挿通するための孔である。 Further, as shown in FIG. 2, the electrostatic chuck 100 is formed with a pin insertion hole 140 extending in the up-down direction from the lower surface S4 of the base member 20 to the suction surface S1 of the plate-shaped member 10. That is, the pin insertion hole 140 includes the hole 26 penetrating the base member 20 in the Z-axis direction, the hole 36 penetrating the joint portion 30 in the Z-axis direction, the plate-shaped member 10 and the metallized layer 60 described later in the Z-axis. The hole 16 penetrating in the direction is an integral hole communicating with each other. The pin insertion hole 140 is a hole for inserting a lift pin (not shown) for pushing up the wafer W held on the suction surface S1 of the plate-shaped member 10 and separating it from the suction surface S1.

また、図２に示すように、静電チャック１００は、板状部材１０とウェハＷとの間の伝熱性を高めてウェハＷの温度分布の制御性をさらに高めるため、板状部材１０の吸着面Ｓ１とウェハＷの表面との間に存在する空間に不活性ガス（例えば、ヘリウムガス）を供給する構成を備えている。すなわち、静電チャック１００には、ベース部材２０の下面Ｓ４から接合部３０の上面にわたって上下方向に延びる第１のガス流路孔１３１と、第１のガス流路孔１３１に連通すると共に板状部材１０の吸着面Ｓ１に開口する第２のガス流路孔１３２とが形成されている。第１のガス流路孔１３１は、ベース部材２０をＺ軸方向に貫通する孔２５と、接合部３０をＺ軸方向に貫通する孔３５とが互いに連通した一体の孔である。また、第２のガス流路孔１３２の下端部は、径が拡大された拡径部１３４となっており、拡径部１３４内には、通気性を有する充填部材（通気性プラグ）１６０が充填されている。また、板状部材１０の内部には、第２のガス流路孔１３２と連通すると共に面方向に環状に延びる横流路１３３が形成されている。ヘリウムガス源（図示しない）から供給されたヘリウムガスが、第１のガス流路孔１３１内に流入すると、流入したヘリウムガスは、第１のガス流路孔１３１から拡径部１３４内に充填された通気性を有する充填部材１６０の内部を通過して板状部材１０の内部の第２のガス流路孔１３２内に流入し、横流路１３３を介して面方向に流れつつ、吸着面Ｓ１に形成されたガス噴出孔から噴出する。このようにして、吸着面Ｓ１とウェハＷの表面との間に存在する空間に、ヘリウムガスが供給される。 In addition, as shown in FIG. 2, the electrostatic chuck 100 enhances heat transfer between the plate-shaped member 10 and the wafer W to further enhance controllability of the temperature distribution of the wafer W. It is provided with a configuration for supplying an inert gas (for example, helium gas) to the space existing between the surface S1 and the surface of the wafer W. That is, in the electrostatic chuck 100, a first gas passage hole 131 extending in the up-down direction from the lower surface S4 of the base member 20 to the upper surface of the joining portion 30, and a plate-like member that communicates with the first gas passage hole 131. A second gas passage hole 132 that opens to the adsorption surface S1 of the member 10 is formed. The first gas passage hole 131 is an integral hole in which a hole 25 penetrating the base member 20 in the Z-axis direction and a hole 35 penetrating the joint portion 30 in the Z-axis direction are in communication with each other. Further, the lower end of the second gas passage hole 132 is an enlarged diameter portion 134 having an enlarged diameter, and a filling member (air permeable plug) 160 having air permeability is provided in the enlarged diameter portion 134. It is filled. Further, inside the plate-shaped member 10, there is formed a lateral flow passage 133 which communicates with the second gas flow passage hole 132 and extends annularly in the plane direction. When the helium gas supplied from the helium gas source (not shown) flows into the first gas passage hole 131, the inflowing helium gas is filled in the expanded diameter portion 134 from the first gas passage hole 131. The adsorbing surface S1 while passing through the inside of the filled gas-permeable filling member 160, flowing into the second gas flow path hole 132 inside the plate-shaped member 10 and flowing in the surface direction through the lateral flow path 133. It is ejected from the gas ejection hole formed in the. In this way, the helium gas is supplied to the space existing between the suction surface S1 and the surface of the wafer W.

Ａ−２．板状部材１０とベース部材２０とを接合するための詳細構成：
次に、板状部材１０とベース部材２０とを接合するための詳細構成について説明する。図３は、本実施形態における静電チャック１００のＸＹ断面構成を概略的に示す説明図である。図３には、図２のＩＩＩ−ＩＩＩの位置における静電チャック１００のＸＹ断面構成が示されている。また、図３には、板状部材１０の外形が点線で示されている。 A-2. Detailed structure for joining the plate member 10 and the base member 20:
Next, a detailed configuration for joining the plate member 10 and the base member 20 will be described. FIG. 3 is an explanatory diagram schematically showing the XY cross-sectional structure of the electrostatic chuck 100 in this embodiment. FIG. 3 shows an XY sectional configuration of the electrostatic chuck 100 at the position III-III in FIG. Further, in FIG. 3, the outer shape of the plate member 10 is shown by a dotted line.

図２および図３に示すように、本実施形態の静電チャック１００では、板状部材１０の下面Ｓ２には、メタライズ層６０が形成されている。メタライズ層６０は、板状部材１０の下面Ｓ２のうち、孔１６や拡径部１３４の形成部分を除く、表面部分全体を覆っている。メタライズ層６０は、主成分として、導電性材料（例えば、Ａｇ、Ｃｕ、Ａｕ、Ｐｔ、Ｐｂ、Ｎｉ−Ａｕフラッシュなど）を含む材料により形成された金属膜である。メタライズ層６０のＺ軸方向の厚さは、板状部材１０のＺ軸方向の厚さより薄く、例えば０．１μｍ程度である。 As shown in FIGS. 2 and 3, in the electrostatic chuck 100 of this embodiment, the metallized layer 60 is formed on the lower surface S2 of the plate-shaped member 10. The metallized layer 60 covers the entire surface portion of the lower surface S2 of the plate-shaped member 10 excluding the portions where the holes 16 and the enlarged diameter portions 134 are formed. The metallized layer 60 is a metal film formed of a material containing a conductive material (for example, Ag, Cu, Au, Pt, Pb, Ni—Au flash, etc.) as a main component. The thickness of the metallized layer 60 in the Z-axis direction is smaller than the thickness of the plate-shaped member 10 in the Z-axis direction, for example, about 0.1 μm.

接合部３０は、金属を含む多孔質構造により形成されている。接合部３０の多孔質構造の気孔率は、板状部材１０の気孔率より高く、かつ、ベース部材２０の気孔率より高い。接合部３０の多孔質構造の気孔率は、例えば、２０％以上、７０％以下である。また、接合部３０は、主成分として、粒径が１００ｎｍ以下の金属超微粒子を含んでいる。具体的には、接合部３０は、金属ナノ粒子（例えばＡｇナノ粒子やＣｕナノ粒子）の焼結体である。ここでいう主成分とは、含有割合（重量割合）の最も多い成分を意味する。接合部３０は、複数の金属ナノ粒子が焼結して互いに接合したナノ金属粒子接合体である。このナノ金属粒子接合は、金属ナノ粒子同士の固相拡散接合（固相焼結）である。このため、接合部３０では、金属ナノ粒子同士が固相（粒状）のまま接合することによって固相間に気孔が形成されており、その結果、接合部３０は多孔質構造になっている。 The joint portion 30 is formed of a porous structure containing metal. The porosity of the porous structure of the joint portion 30 is higher than that of the plate member 10 and higher than that of the base member 20. The porosity of the porous structure of the bonding portion 30 is, for example, 20% or more and 70% or less. Further, the bonding portion 30 contains, as a main component, ultrafine metal particles having a particle diameter of 100 nm or less. Specifically, the joint portion 30 is a sintered body of metal nanoparticles (for example, Ag nanoparticles or Cu nanoparticles). The main component as used herein means a component having the largest content ratio (weight ratio). The joint portion 30 is a nanometal particle joined body in which a plurality of metal nanoparticles are sintered and joined to each other. This nano metal particle bonding is solid phase diffusion bonding (solid phase sintering) of metal nanoparticles. Therefore, in the bonding portion 30, the metal nanoparticles are bonded to each other in the solid phase (granular state) to form pores between the solid phases, and as a result, the bonding portion 30 has a porous structure.

本実施形態の静電チャック１００は、接合部３０に関する第１の条件を満たす。
＜第１の条件＞
接合部３０は、複数の多孔質部３２によって形成されており、かつ、接合部３０を含むＺ軸方向に略垂直な少なくとも１つの断面において、少なくとも１組の多孔質部３２同士の間には、隙間Ｍが存在している（図２および図３参照）。
隙間Ｍは、接合部３０（多孔質部３２）のＺ軸方向の全長にわたって多孔質部３２の形成材料が連続的に存在しない（図２参照）。また、１つの隙間Ｍの開口面積は、多孔質部３２の気孔の開口面積（気孔径が最大の気孔の開口面積）より大きい（図３参照）。例えば、１つの隙間Ｍの開口面積は、多孔質部３２の気孔の開口面積の１０倍以上であることが好ましい。なお、隙間Ｍは、Ｚ軸方向に沿って直線状に延びているものに限らず、Ｚ軸方向に対して傾斜した方向に延びているものや、例えば曲線など、非直線状に延びているものでもよい。 The electrostatic chuck 100 of the present embodiment satisfies the first condition regarding the bonding section 30.
<First condition>
The joint portion 30 is formed by a plurality of porous portions 32, and in at least one cross section substantially perpendicular to the Z-axis direction including the joint portion 30, between the at least one pair of porous portions 32. , M is present (see FIGS. 2 and 3).
In the gap M, the material forming the porous portion 32 does not continuously exist over the entire length of the joint portion 30 (porous portion 32) in the Z-axis direction (see FIG. 2). Further, the opening area of one gap M is larger than the opening area of the pores of the porous portion 32 (the opening area of the pores having the largest pore diameter) (see FIG. 3). For example, the opening area of one gap M is preferably 10 times or more the opening area of the pores of the porous portion 32. The gap M is not limited to linearly extending along the Z-axis direction, but may extend in a direction inclined with respect to the Z-axis direction or non-linearly extending, for example, a curve. It may be one.

本実施形態の静電チャック１００は、さらに、接合部３０に関する第２の条件を満たすことが好ましい。
＜第２の条件＞
Ｚ軸方向視で、静電チャック１００の下面Ｓ２の全体の面積に対する、隙間Ｍの面積の割合（以下、「隙間Ｍの面積割合」という）は、０．５％以上である。
隙間Ｍの面積は、静電チャック１００の下面Ｓ２と隙間Ｍとが重なる重複領域の総面積である。なお、静電チャック１００の下面Ｓ２は、特許請求の範囲における対象表面に相当する。 It is preferable that the electrostatic chuck 100 of the present embodiment further satisfy the second condition regarding the bonding portion 30.
<Second condition>
The ratio of the area of the gap M to the entire area of the lower surface S2 of the electrostatic chuck 100 (hereinafter, referred to as “area ratio of the gap M”) is 0.5% or more when viewed in the Z-axis direction.
The area of the gap M is the total area of the overlapping region where the lower surface S2 of the electrostatic chuck 100 and the gap M overlap. The lower surface S2 of the electrostatic chuck 100 corresponds to the target surface in the claims.

本実施形態の静電チャック１００は、さらに、接合部３０に関する第３の条件を満たすことが好ましい。
＜第３の条件＞
接合部３０の隙間Ｍの面積割合は、５０％以下である。 It is preferable that the electrostatic chuck 100 according to the present embodiment further satisfy the third condition regarding the bonding portion 30.
<Third condition>
The area ratio of the gap M of the joint portion 30 is 50% or less.

本実施形態の静電チャック１００は、さらに、接合部３０に関する第４の条件を満たすことが好ましい。
＜第４の条件＞
接合部３０を含むＺ軸方向に略垂直な少なくとも１つの断面において、複数の多孔質部３２のうち、少なくとも２つの多孔質部３２は、多孔質部３２より幅が狭い接続部分３４を介して結合している（図３参照）。 It is preferable that the electrostatic chuck 100 according to the present embodiment further satisfy the fourth condition regarding the bonding portion 30.
<Fourth condition>
In at least one cross section that is substantially perpendicular to the Z-axis direction including the joint portion 30, at least two porous portions 32 among the plurality of porous portions 32 are connected via a connecting portion 34 that is narrower than the porous portion 32. Are bound (see Figure 3).

本実施形態の静電チャック１００は、さらに、接合部３０に関する第５の条件を満たすことが好ましい。
＜第５の条件＞
接合部３０を含むＺ軸方向に略垂直な少なくとも１つの断面において、少なくとも１つの隙間Ｍは、該隙間Ｍの全周にわたって複数の多孔質部３２に囲まれている。 It is preferable that the electrostatic chuck 100 according to the present embodiment further satisfy the fifth condition regarding the bonding portion 30.
<Fifth condition>
In at least one cross section substantially perpendicular to the Z-axis direction including the joint portion 30, at least one gap M is surrounded by a plurality of porous portions 32 over the entire circumference of the gap M.

本実施形態の静電チャック１００は、さらに、接合部３０に関する第６の条件を満たすことが好ましい。
＜第６の条件＞
接合部３０を含むＺ軸方向に略垂直な少なくとも１つの断面において、少なくとも互いに隣り合う１組の多孔質部３２について、１組の多孔質部３２のそれぞれの外接円の中心間距離Ｌは、外接円の半径の２倍以下である。
ここで、「外接円の中心間距離Ｌ」は、互いに隣り合う１組の多孔質部３２の一方の外接円の中心（例えば、図３中の外接円Ｃ１の中心Ｏ１）と、他方の外接円の中心（例えば、図３中の外接円Ｃ２の中心Ｏ２）との間の距離である。また、「外接円の半径」は、１組の多孔質部３２のそれぞれの外接円のうち、半径が大きい外接円の半径である。 It is preferable that the electrostatic chuck 100 according to the present embodiment further satisfy the sixth condition regarding the bonding portion 30.
<Sixth condition>
In at least one cross section substantially perpendicular to the Z-axis direction including the joint portion 30, the center-to-center distance L of each circumscribed circle of one set of porous portions 32 is at least for one set of porous portions 32 adjacent to each other, It is not more than twice the radius of the circumscribed circle.
Here, the "center-to-center distance L of the circumscribing circle" means the center of one circumscribing circle of the pair of porous portions 32 adjacent to each other (for example, the center O1 of the circumscribing circle C1 in FIG. 3) and the circumscribing the other. It is the distance from the center of the circle (for example, the center O2 of the circumscribed circle C2 in FIG. 3). The “radius of the circumscribing circle” is the radius of the circumscribing circle having the largest radius among the circumscribing circles of the pair of porous portions 32.

本実施形態の静電チャック１００は、さらに、接合部３０に関する第７の条件を満たすことが好ましい。
＜第７の条件＞
接合部３０を含むＺ軸方向に略垂直な少なくとも１つの断面において、少なくとも互いに隣り合う１組の多孔質部３２について、１組の多孔質部３２のそれぞれの外接円の中心間距離Ｌは、外接円の半径の１．５倍以上である。 It is preferable that the electrostatic chuck 100 according to the present embodiment further satisfy the seventh condition regarding the bonding portion 30.
<Seventh condition>
In at least one cross section substantially perpendicular to the Z-axis direction including the joint portion 30, the center-to-center distance L of each circumscribed circle of one set of porous portions 32 is at least for one set of porous portions 32 adjacent to each other, It is at least 1.5 times the radius of the circumscribed circle.

なお、図３では、各多孔質部３２のＺ軸方向視での形状は、略円形であり、複数の多孔質部３２は、Ｚ軸方向視で格子状に配置されている。また、互いに隣り合う多孔質部３２のそれぞれの周縁の一部分同士が互いに一体的に結合されている。また、接合部３０には、複数の隙間Ｍが形成されている。具体的には、複数の隙間Ｍは、互いに直交する２方向（Ｘ軸方向、Ｙ軸方向）において互いに等間隔で配置されている。 In FIG. 3, the shape of each porous portion 32 as viewed in the Z-axis direction is substantially circular, and the plurality of porous portions 32 are arranged in a lattice shape when viewed in the Z-axis direction. Moreover, a part of each peripheral edge of the porous portions 32 adjacent to each other is integrally coupled to each other. Further, a plurality of gaps M are formed in the joint portion 30. Specifically, the plurality of gaps M are arranged at equal intervals in two directions orthogonal to each other (X-axis direction, Y-axis direction).

Ａ−３．静電チャック１００の製造方法：
本実施形態の静電チャック１００の製造方法は、例えば以下の通りである。まず、公知の方法により、板状部材１０を作製する。例えば、セラミックスグリーンシートを複数枚作製し、所定のセラミックスグリーンシートに所定の加工を行う。所定の加工としては、例えば、チャック電極４０やヒータ電極５０等の形成のためのメタライズペーストの印刷、各種ビアの形成のための孔空けおよびメタライズペーストの充填等が挙げられる。これらのセラミックスグリーンシートを積層して熱圧着し、切断等の加工を行うことにより、セラミックスグリーンシートの積層体を作製する。作製されたセラミックスグリーンシートの積層体を焼成することにより、セラミックス焼成体である板状部材１０を作製する。また、公知の方法により、ベース部材２０を作製する。 A-3. Manufacturing method of the electrostatic chuck 100:
The method of manufacturing the electrostatic chuck 100 of this embodiment is as follows, for example. First, the plate member 10 is manufactured by a known method. For example, a plurality of ceramic green sheets are produced, and a predetermined ceramic green sheet is subjected to predetermined processing. Examples of the predetermined processing include printing a metallizing paste for forming the chuck electrode 40, the heater electrode 50, etc., forming holes for forming various vias, and filling the metallizing paste. By laminating these ceramic green sheets, thermocompression-bonding and performing processing such as cutting, a laminated body of ceramic green sheets is produced. The plate-shaped member 10 which is a ceramic fired body is produced by firing the produced ceramic green sheet laminate. Further, the base member 20 is manufactured by a known method.

次に、板状部材１０の下面Ｓ２にメタライズ層６０を形成する。例えば、板状部材１０がアルミナにより形成されている場合、板状部材１０の下面Ｓ２に、モリブデンマンガン法やコファイア法により金属膜（例えばＮｉ等のストライクメッキ）を形成した後にＡｇ、Ｃｕ、Ａｕ等のめっきを施す。これにより、ベース部材２０の上面Ｓ３側に配置される最外層がＡｇ、Ｃｕ、Ａｕ等により形成されたメタライズ層６０を形成することができる。なお、メタライズ層６０を形成する他の方法としては、金属蒸着、スパッタ、物理蒸着（ＰＶＤ）が挙げられる。なお、板状部材１０とメタライズ層６０との密着性向上のため、例えば、板状部材１０の下面Ｓ２側から、Ｔｉ、Ｍｏ、最外層（約０．１μｍ）の順に成膜してもよい。 Next, the metallized layer 60 is formed on the lower surface S2 of the plate member 10. For example, when the plate-shaped member 10 is made of alumina, a metal film (for example, strike plating of Ni or the like) is formed on the lower surface S2 of the plate-shaped member 10 by a molybdenum-manganese method or a co-firing method, and then Ag, Cu, Au is formed. And so on. Thereby, the metallized layer 60 in which the outermost layer disposed on the upper surface S3 side of the base member 20 is formed of Ag, Cu, Au, or the like can be formed. Other methods of forming the metallized layer 60 include metal vapor deposition, sputtering, and physical vapor deposition (PVD). In order to improve the adhesion between the plate member 10 and the metallized layer 60, for example, Ti, Mo, and the outermost layer (about 0.1 μm) may be formed in this order from the lower surface S2 side of the plate member 10. ..

次に、金属ナノ粒子を主成分とするペーストを、ベース部材２０の上面Ｓ３上にドット状に塗布（印刷）する。図４は、ベース部材２０の上面Ｓ３上に塗布された複数のドット状のペースト（以下、「接合部前駆体３１」という）のＸＹ平面上の配置構成を示す説明図である。図４には、板状部材１０の外形が点線で示されている。図４では、各接合部前駆体３１のＺ軸方向視での形状は、略円形状であり、複数の接合部前駆体３１は、互いに離間して配置され、かつ、互いに等間隔で格子状に配置されている。次に、ベース部材２０の上面Ｓ３上に塗布された複数の接合部前駆体３１の上に板状部材１０をマウントすることにより、板状部材１０に形成されたメタライズ層６０の下面Ｓ５とベース部材２０の上面Ｓ３との間に複数の接合部前駆体３１を挟み込ませる。そして、板状部材１０に対して、ベース部材２０側に向かう方向に、例えば、約０．１Ｎ／ｍｍ^２〜１．０Ｎ／ｍｍ^２程度の圧力を加え、窒素雰囲気で２７０℃の熱処理を１時間施すことにより、板状部材１０に形成されたメタライズ層６０とベース部材２０とを接合する接合部３０を形成する。すなわち、熱処理の過程で、各接合部前駆体３１は外周側に広がって、互いに隣り合う接合部前駆体３１の周縁の一部分同士が接触して一体化する。その結果、少なくとも上記第１の条件を満たす接合部３０が形成される（図２および図３参照）。以上の工程により、本実施形態の静電チャック１００が製造される。 Next, a paste containing metal nanoparticles as a main component is applied (printed) in a dot shape on the upper surface S3 of the base member 20. FIG. 4 is an explanatory diagram showing an arrangement configuration on the XY plane of a plurality of dot-shaped pastes (hereinafter, referred to as “joint part precursors 31”) applied on the upper surface S3 of the base member 20. In FIG. 4, the outer shape of the plate member 10 is shown by a dotted line. In FIG. 4, the shape of each joint precursor 31 when viewed in the Z-axis direction is a substantially circular shape, and the plurality of joint precursors 31 are arranged so as to be spaced apart from each other, and are arranged in a grid pattern at equal intervals. It is located in. Next, by mounting the plate-shaped member 10 on the plurality of joint precursors 31 applied on the upper surface S3 of the base member 20, the lower surface S5 of the metallized layer 60 formed on the plate-shaped member 10 and the base. A plurality of bonding portion precursors 31 are sandwiched between the member 20 and the upper surface S3. Then, the plate-like member 10, toward the base member 20 side, for example, from about 0.1N ^/ mm ² ~1.0N ^/ mm 2 pressure of about added and the heat treatment of 270 ° C. in a nitrogen atmosphere 1 By applying for a period of time, the bonding portion 30 that bonds the metallized layer 60 formed on the plate-shaped member 10 and the base member 20 is formed. That is, in the process of heat treatment, each joint precursor 31 spreads to the outer peripheral side, and part of the peripheral edges of the joint precursors 31 adjacent to each other come into contact with each other to be integrated. As a result, the joint portion 30 satisfying at least the first condition is formed (see FIGS. 2 and 3). Through the above steps, the electrostatic chuck 100 of this embodiment is manufactured.

Ａ−４．本実施形態の効果：
以上説明したように、本実施形態の静電チャック１００は、板状部材１０と、ベース部材２０と、接合部３０とを備える。接合部３０は、板状部材１０およびベース部材２０より気孔率が高い複数の多孔質部３２によって形成されている。このため、本実施形態では、接合部が緻密体によって形成された構成に比べて、板状部材１０とベース部材２０との熱膨張差による応力を緩和する応力緩和性が向上する。また、本実施形態では、少なくとも２つの多孔質部３２の間には、隙間Ｍが存在している（上記第１の条件）。隙間Ｍは、接合部３０のＺ軸方向の全長にわたって接合部３０の形成材料が連続的に存在せず、かつ、Ｚ軸方向に略垂直な少なくとも１つの断面における開口面積が多孔質部３２の気孔の開口面積より大きい空間である。このため、本実施形態では、接合部３０（多孔質部３２）に発生したクラックの進展は、接合部３０に形成された隙間Ｍによって遮断される。以上により、本実施形態によれば、接合部に隙間が存在しない構成に比べて、接合部３０における応力緩和性を向上させつつ、接合部３０におけるクラックの進展を抑制することができる。 A-4. Effects of this embodiment:
As described above, the electrostatic chuck 100 according to this embodiment includes the plate member 10, the base member 20, and the joining portion 30. The joint portion 30 is formed by a plurality of porous portions 32 having a higher porosity than the plate member 10 and the base member 20. Therefore, in the present embodiment, the stress relaxation property for relaxing the stress due to the difference in thermal expansion between the plate-shaped member 10 and the base member 20 is improved as compared with the configuration in which the joint portion is formed of the dense body. Further, in the present embodiment, a gap M exists between at least two porous parts 32 (first condition described above). The gap M is such that the material forming the joint 30 does not continuously exist over the entire length of the joint 30 in the Z-axis direction, and the opening area in at least one cross section substantially perpendicular to the Z-axis is the porous portion 32. It is a space larger than the opening area of the pores. Therefore, in the present embodiment, the progress of the crack generated in the joint portion 30 (the porous portion 32) is blocked by the gap M formed in the joint portion 30. As described above, according to the present embodiment, it is possible to suppress the progress of cracks in the joint portion 30 while improving the stress relaxation property in the joint portion 30 as compared with the configuration in which there is no gap in the joint portion.

ここで、接合部に隙間が存在しない構成において、接合部を比較的に気孔率が高い多孔質構造にすることによって接合部における応力緩和性を向上させることも考えられる。しかし、多孔質構造の気孔率が高いほど、各気孔の開口面積が大きいため、接合部と被接合部材（板状部材１０やベース部材２０）との間の接触箇所におけるアンカー効果が低下するため、接合部と被接合部材とが十分に接合されないおそれがある。これに対して、本実施形態によれば、接合部３０を形成する多孔質部３２に隙間Ｍが存在している。このため、多孔質部３２において気孔率に起因するアンカー効果の低下を抑制しつつ、接合部３０に形成された隙間Ｍによって接合部における応力緩和性を向上させることができる。なお、本実施形態では、セラミックスにより形成された板状部材１０の下面Ｓ２にメタライズ層６０が形成され、このメタライズ層６０とベース部材２０とが、接合部３０を形成する多孔質体によって接合されている。このため、板状部材１０と多孔質体とが、メタライズ層６０を介さずに直接接触する構成に比べて、板状部材１０と多孔質体との接合強度が向上する。 Here, in a structure in which there are no gaps in the joint, it is conceivable that the joint may have a porous structure having a relatively high porosity to improve the stress relaxation property in the joint. However, since the higher the porosity of the porous structure, the larger the opening area of each pore, the anchor effect at the contact point between the joint and the member to be joined (the plate member 10 or the base member 20) decreases. However, there is a possibility that the joint and the member to be joined are not sufficiently joined. On the other hand, according to the present embodiment, the gap M exists in the porous portion 32 forming the joint portion 30. Therefore, it is possible to improve the stress relaxation property in the joint portion by the gap M formed in the joint portion 30 while suppressing the decrease in the anchor effect due to the porosity in the porous portion 32. In the present embodiment, the metallized layer 60 is formed on the lower surface S2 of the plate-shaped member 10 made of ceramics, and the metallized layer 60 and the base member 20 are joined by the porous body forming the joint portion 30. ing. Therefore, the bonding strength between the plate-shaped member 10 and the porous body is improved as compared with the configuration in which the plate-shaped member 10 and the porous body are in direct contact with each other without the metallized layer 60.

本実施形態では、接合部３０の隙間Ｍの面積割合は、０．５％以上である（上記第２の条件）。これにより、本実施形態によれば、隙間Ｍの面積割合が０．５％未満である構成に比べて、隙間Ｍの存在によって接合部３０の柔軟性が高いため、接合部３０におけるクラックの進展を、より効果的に抑制することができる。 In the present embodiment, the area ratio of the gap M of the joint portion 30 is 0.5% or more (the second condition described above). As a result, according to the present embodiment, the flexibility of the joint portion 30 is high due to the existence of the gap M, as compared with the configuration in which the area ratio of the gap M is less than 0.5%. Can be suppressed more effectively.

本実施形態では、接合部３０の隙間Ｍの面積割合は、５０％以下である（上記第３の条件）。これにより、本実施形態によれば、隙間Ｍの面積割合が５０％より高い構成に比べて、接合部と板状部材１０等との接触面積が大きいため、板状部材１０とベース部材２０との接合部３０による接合強度の低下を、より効果的に抑制することができる。 In the present embodiment, the area ratio of the gap M of the joint portion 30 is 50% or less (the third condition described above). Thus, according to the present embodiment, the contact area between the joint portion and the plate-shaped member 10 and the like is larger than that in the configuration in which the area ratio of the gap M is higher than 50%, so that the plate-shaped member 10 and the base member 20 are It is possible to more effectively suppress the decrease in the bonding strength due to the bonding portion 30.

本実施形態では、多孔質部３２同士が接続部分３４（くびれ）を介して結合されている（上記第４の条件）。これにより、本実施形態によれば、多孔質部３２同士の隙間を確保しつつ、多孔質部３２同士が結合されていない構成に比べて、多孔質部３２同士が補強し合うことにより接合部３０全体として強度を向上させることができる。 In the present embodiment, the porous portions 32 are connected to each other via the connection portion 34 (constriction) (the fourth condition described above). As a result, according to the present embodiment, as compared with the configuration in which the porous portions 32 are not bonded to each other while the gap between the porous portions 32 is secured, the porous portions 32 reinforce each other and thereby the joint portion. The strength of the entire 30 can be improved.

本実施形態では、接合部３０に存在する少なくとも１つの隙間Ｍは、少なくとも１つのＸＹ断面において、隙間Ｍの全周にわたって多孔質部３２に囲まれている（上記第５の条件）。これにより、本実施形態によれば、隙間Ｍの一部が接合部の外周面まで連続的につながっている構成に比べて、隙間Ｍの周囲の強度低下を抑制することができる。 In the present embodiment, at least one gap M existing in the joint portion 30 is surrounded by the porous portion 32 over the entire circumference of the gap M in at least one XY cross section (the fifth condition). As a result, according to the present embodiment, it is possible to suppress a decrease in strength around the gap M, as compared with a configuration in which a part of the gap M is continuously connected to the outer peripheral surface of the joint portion.

本実施形態では、少なくとも１つのＸＹ断面において、少なくとも互いに隣り合う１組の多孔質部３２について、１組の多孔質部３２のそれぞれの外接円の中心間距離Ｌは、外接円の半径の２倍以下である（上記第６の条件）。これにより、本実施形態によれば、１組の多孔質部３２のそれぞれの外接円の中心間距離Ｌが外接円の半径の２倍より長い構成に比べて、隙間Ｍの存在に起因して接合部３０による接合強度が低下することを抑制することができる。 In this embodiment, the center-to-center distance L of each circumscribed circle of one set of porous portions 32 is at least 2 times the radius of the circumscribed circle in at least one set of porous portions 32 adjacent to each other in at least one XY cross section. It is less than or equal to twice (the above sixth condition). Thus, according to the present embodiment, the distance M between the centers of the circumscribing circles of the pair of porous portions 32 is caused by the existence of the gap M, as compared with the configuration in which the radius L of the circumscribing circle is longer than twice the radius of the circumscribing circle. It is possible to prevent the joint strength of the joint portion 30 from decreasing.

本実施形態では、少なくとも１つのＸＹ断面において、少なくとも互いに隣り合う１組の多孔質部３２について、１組の多孔質部３２のそれぞれの外接円の中心間距離Ｌは、外接円の半径の１．５倍以上である（上記第７の条件）。これにより、本実施形態によれば、１組の多孔質部３２のそれぞれの外接円の中心間距離Ｌが外接円の半径の１．５倍より短い構成に比べて、接合部３０に生じるクラックの進展を、より確実に抑制することができる。 In this embodiment, the center-to-center distance L of each circumscribed circle of one set of porous portions 32 is at least one radius of the circumscribed circle in at least one set of porous portions 32 adjacent to each other in at least one XY cross section. 5 times or more (seventh condition above). As a result, according to the present embodiment, the cracks that occur in the joint portion 30 are smaller than in the configuration in which the center-to-center distance L of each circumscribed circle of the set of porous portions 32 is shorter than 1.5 times the radius of the circumscribed circle. The progress of can be suppressed more reliably.

また、本実施形態では、接合部３０は、主成分として、粒径が１００ｎｍ以下の金属超微粒子を含んでいるため、接合部が主成分として樹脂や半田を含む構成に比べて、接合部３０の耐熱性を向上させることができる。例えば、接合部３０が、Ａｇナノ粒子により形成された構成では、接合部３０の融点は約９６０℃である。また、接合部３０では、２００℃程度で接合が可能であるため、接合時における残留応力を最小限に抑えることができる。また、特に、接合部３０が軟質性を有するＡｇやＣｕの金属超微粒子により形成された構成では、板状部材１０とベース部材２０との熱膨張差による応力を緩和する応力緩和性を、より効果的に向上させることができる。 Further, in the present embodiment, since the bonding portion 30 contains ultrafine metal particles having a particle diameter of 100 nm or less as a main component, the bonding portion 30 is more likely to be compared to a configuration in which the bonding portion contains resin or solder as a main component. The heat resistance of can be improved. For example, in the configuration in which the joint portion 30 is formed of Ag nanoparticles, the melting point of the joint portion 30 is about 960 ° C. Further, since the joint portion 30 can be joined at about 200 ° C., the residual stress at the time of joining can be minimized. Further, in particular, in the structure in which the bonding portion 30 is formed of the ultrafine metal particles of Ag or Cu having flexibility, the stress relaxation property for relaxing the stress due to the difference in thermal expansion between the plate-shaped member 10 and the base member 20 is further improved. It can be effectively improved.

Ａ−５．性能評価：
図５は、第１のグループの各サンプルにおける接合部による接合強度とクラック抑制とに関する評価結果を示す説明図であり、図６は、第２のグループの各サンプルにおける接合部による接合強度とクラック抑制とに関する評価結果を示す説明図である。図５および図６に示すように、接合体の２つのグループのサンプルについて、接合部による接合強度とクラック抑制とに関する評価を行った。２つのグループのサンプルは、全体として、上述の静電チャック１００と略同一構成であり、具体的には、アルミナにより形成された矩形状の板状部材と、Ｃｕにより形成された矩形状のベース部材と、接合部とを備える接合体である。但し、各サンプルは、例えばサイズや、板状部材がヒータ電極５０等を備えない等の点で、上述の静電チャック１００とは異なる。板状部材にはメタライズ層が形成されており、メタライズ層とベース部材とが、主成分としてＡｇナノ粒子を含む接合部によって接合されている。なお、各サンプルは、上述した製造方法と同様の方法により製造できる。 A-5. Performance evaluation:
FIG. 5 is an explanatory diagram showing the evaluation results regarding the joint strength and the crack suppression by the joint portion in each sample of the first group, and FIG. 6 is the joint strength and the crack by the joint portion in each sample of the second group. It is explanatory drawing which shows the evaluation result regarding suppression. As shown in FIG. 5 and FIG. 6, the samples of the two groups of bonded bodies were evaluated regarding the bonding strength by the bonded portion and crack suppression. The samples of the two groups as a whole have substantially the same structure as the electrostatic chuck 100 described above, and specifically, a rectangular plate member made of alumina and a rectangular base made of Cu. It is a joined body including a member and a joined portion. However, each sample is different from the electrostatic chuck 100 described above in, for example, the size and the plate-shaped member not including the heater electrode 50 and the like. A metallized layer is formed on the plate-shaped member, and the metallized layer and the base member are joined by a joining portion containing Ag nanoparticles as a main component. Each sample can be manufactured by the same method as the above-mentioned manufacturing method.

図５に示すように、第１のグループのサンプル（サンプル１−１〜１−５）は、接合部３０の隙間Ｍの面積割合が互いに異なる。各サンプルにおける接合部３０の隙間Ｍの面積割合は、接合体の製造段階における各接合部前駆体の大きさや離間距離と、板状部材とベース部材とで接合部前駆体を挟み込む圧力と、の少なくとも１つを変えることにより調整することができる。具体的には、接合部前駆体の大きさが大きいほど、接合部前駆体同士の離間距離が短いほど、板状部材とベース部材とで接合部を挟み込む圧力が高いほど、隙間Ｍの面積割合を低くすることができる。 As shown in FIG. 5, the first group of samples (Samples 1-1 to 1-5) are different from each other in the area ratio of the gap M of the joint portion 30. The area ratio of the gap M of the joint portion 30 in each sample is determined by the size and separation distance of each joint precursor in the manufacturing step of the joint body, and the pressure for sandwiching the joint precursor between the plate-shaped member and the base member. It can be adjusted by changing at least one. Specifically, the larger the size of the joining portion precursor, the shorter the distance between the joining portion precursors, the higher the pressure for sandwiching the joining portion between the plate-shaped member and the base member, and the greater the area ratio of the gap M. Can be lowered.

図６に示すように、第２のグループのサンプル（サンプル２−１〜２−８）は、接合部における多孔質部の半径と中心間距離との少なくとも１つが互いに異なる。多孔質部の半径と中心間距離とは、隙間Ｍの面積割合と同様、接合体の製造段階における各接合部前駆体の大きさや離間距離と、板状部材とベース部材とで接合部前駆体を挟み込む圧力と、の少なくとも１つを変えることにより調整することができる。 As shown in FIG. 6, the samples of the second group (Samples 2-1 to 2-8) differ from each other in at least one of the radius of the porous portion and the center-to-center distance in the bonded portion. The radius of the porous portion and the center-to-center distance are the same as the area ratio of the gap M, the size and separation distance of each joint precursor in the manufacturing step of the joint, and the joint precursor between the plate-shaped member and the base member. It can be adjusted by changing at least one of the pressure for sandwiching and.

接合部による接合強度は、次のようにして評価した。まず、各サンプルの接合体を、大気中で、１５０℃の加熱処理を、２００時間行った。その後、公知の引張試験機を用いて、各サンプルのうち、ベース部材を固定しつつ、板状部材を引っ張る荷重を加えつつ、荷重を増加させていく。そして、接合部が破断したときの破壊荷重を測定した。接合強度は、破壊荷重を、接合部とメタライズ層との接合面積（接合部を形成する多孔質体の気孔は無視）で除算した値（ＭＰａ）とした。すなわち、ここでいう接合強度は、耐酸化試験後における接合部による接合強度（引っ張り強度）である。図５および図６の「接合強度」では、「○」は、接合強度が４０ＭＰａ以上であったことを意味し、「△」は、接合強度が４０ＭＰａ未満であったことを意味する。 The joint strength at the joint was evaluated as follows. First, the bonded body of each sample was heat-treated at 150 ° C. for 200 hours in the air. Then, using a well-known tensile tester, the load is increased while the base member of each sample is fixed and a load for pulling the plate-shaped member is applied. Then, the breaking load when the joint portion was broken was measured. The bonding strength was a value (MPa) obtained by dividing the breaking load by the bonding area between the bonding portion and the metallized layer (ignoring the pores of the porous body forming the bonding portion). That is, the joint strength here is the joint strength (tensile strength) of the joint after the oxidation resistance test. In the "bonding strength" of Figs. 5 and 6, "○" means that the bonding strength was 40 MPa or more, and "△" means that the bonding strength was less than 40 MPa.

接合部によるクラック抑制は、次のようにして評価した。クラック抑制は、接合部の外表面に発生したクラックの接合部の内部への進展（伝播）を抑制することをいう。まず、各サンプルの接合体を、室温（常温）と３５０℃との間で交互に温度を変える熱サイクルを５０００回繰り返する。その後、接合部におけるクラックの発生率を特定する。クラックの発生率は、Ｚ軸方向視で、該Ｚ軸方向に略直交する所定方向（例えばＸ軸方向）における接合部３０全体の幅に対する、接合部の外表面からクラックが発生した位置まで深さの割合である。各サンプルの接合体から、接合部のＸＹ断面を切り出して、そのＸＹ断面を研磨し、電子顕微鏡により例えば２０，０００倍の倍率で断面観察し、接合部におけるクラックの有無を検出して、接合部におけるクラックの発生率を特定する。なお、各サンプルの接合体を切断せずに、公知のＸ線透過装置に用いて接合部におけるクラックの有無を検出して、クラック発生率を特定してもよい。図５および図６の「クラック抑制」では、「○」は、クラックの発生率が５％未満であったことを意味し、「△」は、クラックの発生率が５％以上であったことを意味する。 The crack suppression by the joint portion was evaluated as follows. Crack suppression refers to suppressing the propagation (propagation) of cracks generated on the outer surface of the joint to the inside of the joint. First, the bonded body of each sample is subjected to a heat cycle in which the temperature is alternately changed between room temperature (normal temperature) and 350 ° C. 5000 times is repeated. After that, the crack occurrence rate at the joint is specified. The crack occurrence rate is the depth from the outer surface of the joint to the position where the crack is generated with respect to the width of the entire joint 30 in a predetermined direction substantially orthogonal to the Z-axis direction (for example, the X-axis direction) when viewed in the Z-axis direction. It is the ratio of From the bonded body of each sample, an XY cross section of the bonded portion is cut out, the XY cross section is polished, and the cross section is observed with an electron microscope at a magnification of, for example, 20,000 times, and the presence or absence of cracks in the bonded portion is detected and bonded. Specify the rate of occurrence of cracks in the area. The crack occurrence rate may be specified by detecting the presence or absence of cracks in the joint using a known X-ray transmission device without cutting the joint of each sample. In “crack suppression” in FIGS. 5 and 6, “◯” means that the crack occurrence rate was less than 5%, and “Δ” indicates that the crack occurrence rate was 5% or more. Means

図５に示すように、クラック抑制に関する評価結果について、サンプル１−１では、「△」と評価され、サンプル１−２〜１−５では、「○」と評価された。このことは、隙間Ｍの面積割合を０．５以上にする（第２の条件を満たす）ことにより、接合部におけるクラックの進展を、より効果的に抑制できることを意味する。また、接合強度に関する評価結果について、サンプル１−１〜１−４では、「○」と評価され、サンプル１−５では、「△」と評価された。このことは、隙間Ｍの面積割合を５０％以下にする（第３の条件を満たす）ことにより、板状部材とベース部材との接合部による接合強度の低下を、より効果的に抑制できることを意味する。 As shown in FIG. 5, the evaluation result regarding crack suppression was evaluated as “Δ” in Sample 1-1 and evaluated as “◯” in Samples 1-2 to 1-5. This means that by setting the area ratio of the gap M to be 0.5 or more (the second condition is satisfied), it is possible to more effectively suppress the development of cracks in the joint portion. Regarding the evaluation results regarding the bonding strength, Samples 1-1 to 1-4 were evaluated as “◯”, and Sample 1-5 was evaluated as “Δ”. This means that by setting the area ratio of the gap M to be 50% or less (the third condition is satisfied), it is possible to more effectively suppress the decrease in the bonding strength due to the bonding portion between the plate-shaped member and the base member. means.

図６に示すように、接合強度に関する評価結果について、サンプル２−１，２−６では、外接円の中心間距離が外接円の半径の２倍より大きく、「△」と評価され、サンプル２−２〜２−５，２−７，２−８では、外接円の中心間距離が外接円の半径の２倍以下であり、「○」と評価された。このことは、１組の多孔質部のそれぞれの外接円の中心間距離を外接円の半径の２倍以下にする（第６の条件を満たす）ことにより、隙間の存在に起因して接合部による接合強度が低下できることを意味する。また、クラック抑制に関する評価結果について、サンプル２−５，２−８では、外接円の中心間距離Ｌが外接円の半径の１．５倍未満であり、「△」と評価され、サンプル２−１〜２−４，２−６，２−７は、外接円の中心間距離が外接円の半径の１．５倍以上であり、「○」と評価された。このことは、１組の多孔質部のそれぞれの外接円の中心間距離を外接円の半径の１．５倍以上にする（第７の条件を満たす）ことにより、接合部に生じるクラックの進展を、より確実に抑制できることを意味する。 As shown in FIG. 6, regarding the evaluation results regarding the bonding strength, in Samples 2-1 and 2-6, the center-to-center distance of the circumscribing circle was larger than twice the radius of the circumscribing circle and was evaluated as “Δ”. In −2 to 2-5, 2-7, and 2-8, the center-to-center distance of the circumscribed circle was not more than twice the radius of the circumscribed circle, and was evaluated as “◯”. This means that the distance between the centers of the circumscribing circles of the pair of porous portions is set to be twice the radius of the circumscribing circle or less (the sixth condition is satisfied), so that the joint portion is caused by the existence of the gap. Means that the bonding strength can be reduced. Further, regarding the evaluation results regarding crack suppression, in Samples 2-5 and 2-8, the center-to-center distance L of the circumscribing circle is less than 1.5 times the radius of the circumscribing circle, and it is evaluated as “Δ”. In Nos. 1 to 2-4, 2-6, and 2-7, the center-to-center distances of the circumscribing circles were 1.5 times or more the radius of the circumscribing circle, and were evaluated as “◯”. This means that when the distance between the centers of the circumscribing circles of the pair of porous parts is set to be 1.5 times or more the radius of the circumscribing circle (the seventh condition is satisfied), the progress of cracks generated in the joint part Is more reliably suppressed.

Ｂ．変形例：
本明細書で開示される技術は、上述の実施形態に限られるものではなく、その要旨を逸脱しない範囲において種々の形態に変形することができ、例えば次のような変形も可能である。 B. Modification:
The technology disclosed in the present specification is not limited to the above-described embodiment, and can be modified into various forms without departing from the gist thereof, for example, the following modifications are also possible.

上記実施形態における静電チャック１００の構成は、あくまで一例であり、種々変形可能である。例えば、上記実施形態では、第１の部材および第２の部材として、板状の板状部材１０やベース部材２０を例示したが、板状以外の形状（例えば円筒状）の部材であってもよい。また、静電チャック１００は、上記第２の条件から第７の条件の少なくとも１つを満たさなくてもよい。 The configuration of the electrostatic chuck 100 in the above embodiment is merely an example, and can be variously modified. For example, although the plate-shaped plate member 10 and the base member 20 are illustrated as the first member and the second member in the above embodiment, members having a shape other than the plate shape (for example, a cylindrical shape) may be used. Good. The electrostatic chuck 100 may not satisfy at least one of the second condition to the seventh condition.

上記実施形態において、多孔質部３２のＺ軸方向視での形状は、円形状に限らす、例えば正方形状、矩形状など、他の形状であってもよい。また、上記実施形態において、複数の多孔質部３２は、互いに離間していてもよい。また、接合部３０に形成される隙間Ｍは、多孔質部３２に囲まれた閉空間に限らず、一部が接合部３０の外周面側に開放した開空間であってもよい。 In the above embodiment, the shape of the porous portion 32 as viewed in the Z-axis direction is not limited to a circular shape, and may be another shape such as a square shape or a rectangular shape. Further, in the above embodiment, the plurality of porous portions 32 may be separated from each other. Further, the gap M formed in the joint portion 30 is not limited to the closed space surrounded by the porous portion 32, and may be an open space partially open to the outer peripheral surface side of the joint portion 30.

上記実施形態では、板状部材１０の内部にヒータ電極５０が配置されているが、必ずしも板状部材１０の内部にヒータ電極５０が配置されている必要はない。また、上記実施形態では、ベース部材２０に冷媒流路２１が形成されているが、必ずしもベース部材２０に冷媒流路２１が形成されている必要はない。また、上記実施形態において、メタライズ層６０を備えず、板状部材１０と接合部３０とがメタライズ層６０を介さずに接合されている構成であってもよい。 In the above embodiment, the heater electrode 50 is arranged inside the plate-shaped member 10, but the heater electrode 50 does not necessarily have to be arranged inside the plate-shaped member 10. Further, in the above-described embodiment, the coolant channel 21 is formed in the base member 20, but the coolant channel 21 does not necessarily have to be formed in the base member 20. Further, in the above embodiment, the metallized layer 60 may not be provided, and the plate-shaped member 10 and the bonding portion 30 may be bonded without the metallized layer 60 interposed therebetween.

上記実施形態では、板状部材１０の内部に１つのチャック電極４０が設けられた単極方式が採用されているが、板状部材１０の内部に一対のチャック電極４０が設けられた双極方式が採用されてもよい。 In the embodiment described above, the monopolar method in which one chuck electrode 40 is provided inside the plate-shaped member 10 is adopted, but the bipolar method in which the pair of chuck electrodes 40 is provided inside the plate-shaped member 10 is adopted. It may be adopted.

上記実施形態の静電チャック１００における各部材の形成材料は、あくまで一例であり、任意に変更可能である。例えば、上記実施形態では、ベース部材２０が、金属により形成されているが、ベース部材２０が、金属以外の材料（例えば、樹脂材料、セラミックス）により形成されるとしてもよい。また、接合部３０は、多孔質体であればよく、金属超微粒子以外の材料（例えば、樹脂、粒径が１００ｎｍより大きい金属粒子）により形成されたものでもよい。また、接合部３０は、主成分とは異なる種類の金属ナノ粒子（Ａｇ、Ｃｕ、Ａｕ、Ｐｔ、Ｐｄ）を微量添加してもよい。 The forming material of each member in the electrostatic chuck 100 of the above embodiment is merely an example, and can be arbitrarily changed. For example, in the above embodiment, the base member 20 is made of metal, but the base member 20 may be made of a material other than metal (for example, a resin material or ceramics). Further, the bonding portion 30 may be a porous body, and may be formed of a material other than the ultrafine metal particles (for example, resin, metal particles having a particle size larger than 100 nm). In addition, the bonding portion 30 may be added with a small amount of metal nanoparticles (Ag, Cu, Au, Pt, Pd) of a type different from the main component.

また、接合部３０が主成分としてＡｇナノ粒子を含む場合、Ａｇと固相で相互拡散が生じやすい元素（状態図において相互に固溶相領域が多い元素Ａｇ、Ｃｕ、Ａｕ、Ｐｔ、Ｐｂ、Ｎｉ−Ａｕフラッシュなど）を、メタライズ層６０の最外層にすることが好ましい。また、上記実施形態において、ベース部材２０がＣｕではなく、例えばＦｅ系材料、Ｔｉ合金、Ａｌ合金により形成されている場合、同金属と接合部３０に含まれるＡｇナノ粒子との相互拡散が起こりにくい。この場合、ベース部材２０の上面Ｓ３にもメタライズ層を形成し、該メタライズ層と接合部との界面について、上述の第１の条件や第２の条件を満たすことが好ましい。 Further, when the bonding portion 30 contains Ag nanoparticles as a main component, an element that easily causes mutual diffusion in a solid phase with Ag (an element having many solid solution phase regions in the phase diagram, Ag, Cu, Au, Pt, Pb, Ni-Au flash) is preferably the outermost layer of the metallization layer 60. Further, in the above embodiment, when the base member 20 is formed of, for example, a Fe-based material, a Ti alloy, or an Al alloy, instead of Cu, mutual diffusion of the metal and Ag nanoparticles contained in the bonding portion 30 occurs. Hateful. In this case, it is preferable to form a metallized layer also on the upper surface S3 of the base member 20 and satisfy the above-described first condition and second condition for the interface between the metallized layer and the bonding portion.

上記実施形態の静電チャック１００の製造方法は、あくまで一例であり、種々変形可能である。 The method of manufacturing the electrostatic chuck 100 according to the above embodiment is merely an example, and various modifications can be made.

本発明は、静電引力を利用してウェハＷを保持する静電チャック１００に限らず、セラミックスにより形成された第１の部材と、第２の部材と、多孔質体により形成された接合部とを備える他の接合体（例えば、真空チャック等）にも同様に適用可能である。 The present invention is not limited to the electrostatic chuck 100 that holds the wafer W by using electrostatic attraction, but also includes a first member made of ceramics, a second member, and a joint formed by a porous body. It is similarly applicable to other bonded bodies including (for example, a vacuum chuck, etc.).

１０：板状部材１６，２５，２６，３５，３６：孔２０：ベース部材２１：冷媒流路３０：接合部３１：接合部前駆体３２：多孔質部３４：接続部分４０：チャック電極５０：ヒータ電極６０：メタライズ層１００：静電チャック１３１：第１のガス流路孔１３２：第２のガス流路孔１３３：横流路１３４：拡径部１４０：ピン挿通孔１６０：充填部材Ｃ１，Ｃ２：外接円Ｌ：中心間距離Ｍ：隙間Ｏ１，Ｏ２：中心Ｓ１：吸着面Ｓ２，Ｓ４，Ｓ５：下面Ｓ３：上面Ｗ：ウェハ 10: Plate-shaped member 16, 25, 26, 35, 36: Hole 20: Base member 21: Refrigerant flow path 30: Joining part 31: Joining part precursor 32: Porous part 34: Connection part 40: Chuck electrode 50: Heater electrode 60: Metallized layer 100: Electrostatic chuck 131: First gas passage hole 132: Second gas passage hole 133: Horizontal passage 134: Expanded portion 140: Pin insertion hole 160: Filling members C1, C2 : Circumscribing circle L: Distance between centers M: Gap O1, O2: Center S1: Adsorption surface S2, S4, S5: Lower surface S3: Upper surface W: Wafer

Claims

A first member having a first surface substantially perpendicular to the first direction;
A second surface, the second surface being arranged such that the second surface is located on the first surface side of the first member, the thermal expansion being different from the coefficient of thermal expansion of the material of the first member; A second member formed of a material having an index,
A joint portion arranged between the first surface of the first member and the second surface of the second member to join the first member and the second member,
In a joined body comprising
The joint is
Is formed by a plurality of porous parts having a higher porosity than the first member and the second member, and
A gap exists between at least two porous portions of the plurality of porous portions, and the gap is formed by continuously forming the material forming the joint portion over the entire length of the joint portion in the first direction. And the opening area in at least one cross section substantially perpendicular to the first direction is larger than the opening area of the pores of the porous portion,
A zygote characterized by that.

The joined body according to claim 1,
Of the target surface having the smaller area between the first surface of the first member and the second surface of the second member, the total of overlapping regions overlapping the gap in the first direction view. The area is 0.5% or more of the area of the target surface,
A zygote characterized by that.

In the joined body according to claim 1 or 2,
Of the target surface having the smaller area between the first surface of the first member and the second surface of the second member, the total of overlapping regions overlapping the gap in the first direction view. The area is 50% or less of the area of the target surface,
A zygote characterized by that.

The joined body according to any one of claims 1 to 3,
In the at least one cross section, at least two porous portions of the plurality of porous portions are connected to each other via a connecting portion having a width narrower than that of the porous portion.
A zygote characterized by that.

The joined body according to any one of claims 1 to 4,
At least one of the gaps is surrounded by the porous portion over the entire circumference in the at least one cross section.
A zygote characterized by that.

The joined body according to any one of claims 1 to 5,
In at least one cross section, at least for one set of porous parts adjacent to each other, the center-to-center distance of each circumscribed circle of each of the one set of porous parts is not more than twice the radius of the circumscribed circle.
A zygote characterized by that.

The joined body according to any one of claims 1 to 6,
In at least one cross section, the distance between the centers of the circumscribed circles of at least one set of porous parts adjacent to each other is 1.5 times or more the radius of the circumscribed circle. ,
A zygote characterized by that.

The joined body according to any one of claims 1 to 7,
The first member is a ceramic member made of ceramics,
The second member is a base member made of metal,
The bonded body is an electrostatic chuck,
A zygote characterized by that.