Wafer placement table and method of manufacturing the same

A method of manufacturing a wafer placement table, the method comprising:

• (a) a step of preparing a first ceramic substrate having a wafer placement surface on an upper surface, and a second ceramic substrate in which a connection member including an upper base and a lower base is embedded;
• (b) a step of forming a bonding surface by grinding the second ceramic substrate so as to expose the upper base of the connection member;
• and
• (c) a step of metal bonding a lower surface of the first ceramic substrate and the bonding surface of the second ceramic substrate,
• wherein the connection member embedded in the second ceramic substrate prepared in step (a) has a portion in which two areas of cross section when the connection member is cut by a pair of parallel planes to the upper base increases from a side of the upper base to a side of the lower base, and
• wherein the connection member is a member in which metal meshes are stacked in multiple stages.

A wafer placement table comprising:

• a first ceramic substrate having a wafer placement surface on an upper surface;
• a second ceramic substrate disposed on a lower surface side of the first ceramic substrate;
• a metal bonding layer that bonds the lower surface of the first ceramic substrate and an upper surface of the second ceramic substrate;
• a connection member including an upper base and a lower base, the connection member being embedded in the second ceramic substrate with the upper base in contact with the metal bonding layer;
• and
• a power supply terminal electrically connected to the lower base of the connection member,
• wherein a shape of the connection member is such that two areas of cross section when the connection member is cut by a pair of parallel planes to the upper base increases from the upper base to the lower base, and
• wherein the shape of the connection member is a truncated hemisphere shape or a shape having a lateral surface inwardly curved as compared with a truncated cone shape.