JP-7857506-B2 - zygote

Inventors

• 三崎 雅斗
• 吉野 浩一
• 服部 亮誉
• ▲のぼり▼ 和宏

Assignees

• ＮＧＫ株式会社

Dates

Publication Date

20260512

Application Date

20241119

Priority Date

20231120

Claims (11)

1. Ceramic plate and A metal matrix composite (MMC) plate is provided opposite one side of the ceramic plate and is composed of (i) Si, C and Ti, or (ii) Al, Si and C. A bonding layer provided between the ceramic plate and the MMC plate, which joins the ceramic plate and the MMC plate, comprising a bonding layer mainly composed of Al, A bonded body comprising the following: the MMC plate has an Al-enriched layer in which Al is distributed at a higher concentration than in other parts of the MMC plate over a predetermined depth D Al from the bonding interface between the bonding layer and the MMC plate, and the depth D Al of the Al-enriched layer is 40 μm or more.
2. The bonded body according to claim 1, wherein the metal matrix composite material (MMC) further comprises Al, or Al and N, in addition to Si, C, and Ti.
3. The bonded body according to claim 1, wherein the metal matrix composite material (MMC) comprises Al, Si, and C.
4. The bonded body according to claim 1, wherein the bonding layer further contains Si as a minor component.
5. The bonded body according to claim 4, wherein the bonding layer further contains Mg as a minor component.
6. The bonded body according to claim 5, wherein the MMC plate has an Mg diffusion layer in which Mg originating from the bonding layer is diffused from the bonding interface between the bonding layer and the MMC plate to a predetermined depth D Mg .
7. The bonded body according to claim 6, wherein the depth D Al of the Al-enriched layer is greater than the depth D Mg of the Mg-diffusing layer, i.e., D Al > D Mg .
8. The joint according to any one of claims 1 to 7, wherein the ceramic plate contains aluminum oxide and/or aluminum nitride, and has embedded internal electrodes.
9. A method for manufacturing a joined body according to any one of claims 1 to 7, characterized in that the ceramic plate, the bonding layer, and the MMC plate are joined by hot pressure welding.
10. The bonded body according to any one of claims 1 to 7, wherein the surface of the MMC plate on the bonding interface side has an arithmetic mean roughness Ra of 0.01 to 1.0 μm.
11. A joint according to any one of claims 1 to 7, which exhibits a joint strength of 200 MPa or more in a four-point bending test.

Description

This disclosure relates to a joint. Circuit formation in semiconductor device manufacturing is generally performed by plasma etching. Plasma etching is carried out by introducing an inert gas into a vacuum chamber within a plasma etching apparatus to create plasma. The plasma etching apparatus is equipped with an electrostatic chuck assembly that functions as a susceptor for holding the wafer to be etched. A typical electrostatic chuck assembly comprises an electrode-embedded ceramic plate that functions as an electrostatic chuck, and a cooling plate that supports the bottom surface of the electrode-embedded ceramic plate. The wafer is electrostatically adsorbed onto the electrode-embedded ceramic plate, and plasma etching is performed while the wafer is fixed to the electrostatic chuck assembly. Meanwhile, the cooling plate is provided on the bottom surface of the electrode-embedded ceramic plate to dissipate the heat generated in the wafer by plasma etching. The electrode-embedded ceramic plate typically has a structure in which internal electrodes such as electrostatic chuck (ESC) electrodes, RF electrodes, and heater electrodes are embedded within a ceramic substrate made of aluminum oxide or aluminum nitride, which has excellent heat resistance and corrosion resistance. As an example of an electrostatic chuck assembly, Patent Document 1 (Japanese Patent Application Publication No. 2009-141204) discloses a substrate holder in which a first substrate made of a first ceramic sintered body and a second substrate made of a second ceramic sintered body are joined via a bonding film of a metal containing Al. This document discloses that the first substrate and the second substrate are joined via a bonding film of a metal containing Al by thermal pressure welding at a pressure of 4 to 20 MPa while heating the metal with the bonding film sandwiched between the first substrate and the second substrate, and it is stated that it is desirable for the metal containing Al to be an Al alloy containing Mg in the range of 0.5 to 5% by weight. Incidentally, metal matrix composites (MMCs) have been attracting attention in recent years. Metal matrix composites are materials that combine a metal matrix composed of metals such as Al or metallic Si with ceramic reinforcing materials such as SiC or TiC, and are known to have advantages such as being lightweight, having high rigidity, high thermal conductivity, and low thermal expansion. Methods for joining metal matrix composites (MMCs) and ceramic materials have been proposed, and Patent Document 2 (Japanese Patent No. 4373538) discloses a joint in which an MMC containing an aluminum alloy as a matrix and a ceramic material are joined via a brazing material made of an Al alloy containing Mg. Japanese Patent Publication No. 2009-141204Patent No. 4373538Japanese Patent Publication No. 2006-196864 For use as a cooling plate in electrostatic chuck assemblies, MMC plates are desirable due to their advantages such as high thermal conductivity and low thermal expansion. Therefore, there is a need to improve the bonding strength in the joint between the MMC plate and the ceramic plate. The present inventors have now discovered that by providing a predetermined bonding layer between an MMC plate and a ceramic plate, and by having an Al-enriched layer on the MMC plate extending to a predetermined depth (thickness) from the bonding interface between the bonding layer and the MMC plate, it is possible to provide a bonded body of a ceramic plate and an MMC plate with high bonding strength. Therefore, an object of the present invention is to provide a joint of ceramic plates and MMC plates having high bonding strength. The following aspects are provided according to this disclosure. [Aspect 1] Ceramic plate and A metal matrix composite (MMC) plate is provided opposite one side of the ceramic plate and is composed of (i) Si, C and Ti, or (ii) Al, Si and C. A bonding layer provided between the ceramic plate and the MMC plate, which joins the ceramic plate and the MMC plate, comprising a bonding layer mainly composed of Al, A bonded body comprising the following: the MMC plate has an Al-enriched layer in which Al is distributed at a higher concentration than in other parts of the MMC plate over a predetermined depth D Al from the bonding interface between the bonding layer and the MMC plate, and the depth D Al of the Al-enriched layer is 40 μm or more. [Aspect 2] The bonded body according to embodiment 1, wherein the metal matrix composite material (MMC) further comprises Al, or Al and N, in addition to Si, C, and Ti. [Appearance 3] The bonded body according to embodiment 1 or 2, wherein the metal matrix composite material (MMC) includes Al, Si, and C. [Aspect 4] The bonded body according to any one of embodiments 1 to 3, wherein the bonding layer further contains Si as a minor component. [Aspect 5] The bonded body according to any one of embodiments 1 to 4, wherein the bonding layer further