Patent ID: 7959734

Claim:
A substrate mounting structure disposed in a pressure reduced space, comprising: a base portion; a pillar portion mounted in a standing manner on said base portion and having an internal space, said pillar portion being a thin-walled cylinder; and a mounting stage supported on said pillar portion and having a substrate mounted thereon, said mounting stage including a heating element that heats the mounted substrate, a controller that controls an electrical power supplied to said heating element based on an electrical signal to which a temperature of the substrate is converted, and a thermal breaking unit that mechanically breaks and connects an electrical power supply line connected to said heating element depending on a temperature of the substrate independently from the control of said controller, wherein said thermal breaking unit is disposed on a side of the internal space of the pillar portion in said mounting stage, wherein a pressure in the internal space is reduced, wherein said mounting stage, which is disk-shaped, includes a concave portion disposed centrally on an under surface of the mounting stage, said thermal breaking unit being housed in the concave portion so as to face a center of the mounted substrate, and wherein said heating element and said electrical power supply line are connected to each other at a portion of the mounting stage other than at the concave portion of said mounting stage.