Electrostatic chuck and substrate fixing device

An electrostatic chuck comprising:

• an insulating substrate having a placement surface on which a suction target object is placed and an opposite surface provided on an opposite side to the placement surface;
• and
• a gas hole penetrating from the opposite surface to the placement surface,
• wherein the gas hole has a first hole portion extending from the opposite surface toward the placement surface, a second hole portion extending from the placement surface toward the opposite surface, and a third hole portion provided between the first hole portion and the second hole portion and formed to communicate the first hole portion and the second hole portion each other,
• wherein the first hole portion is provided not to overlap with the second hole portion in a plan view,
• wherein the insulating substrate has a first insulating layer having the opposite surface, a second insulating layer laminated on the first insulating layer, and a third insulating layer having the placement surface and laminated on the second insulating layer,
• wherein the first hole portion penetrates through the first insulating layer in a thickness direction,
• wherein the second hole portion penetrates through the third insulating layer in the thickness direction, and
• wherein the third hole portion penetrates through the second insulating layer in the thickness direction.