Patent ID: 7303998

Claim:
A plasma processing method for processing a sample by reducing a pressure within a processing chamber comprising the steps of: mounting the sample an a sample holder disposed in the processing chamber; and processing the sample using a plasma generated in the processing chamber above the sample holder while supplying a gas for heat transfer to a spaces between a surface of the sample holder having the sample mounted thereon and a rear surface of the sample; wherein the sample holder has a plurality of substantially ring-shaped depressed portions and another depressed portion disposed in a central side of the plural substantially ring-shaped depressed portions at the surface having the sample mounted thereon and a plurality of refrigerant flow oaths inside the sample holder which includes a central flow oath disposed in a central portion and an outer flow path disposed in an outer periphery portion inside the sample holder, wherein said plural substantially ring-shaped depressed portions include an outer circumferential depressed portion disposed on an outer periphery portion of the sample holder and an inner depressed portion disposed on an inner side of the outer circumferential depressed portion; and setting a temperature distribution of the sample holder higher in the central portion than in the outer periphery and a pressure in a space between the sample and the inner depressed portion arranged between the outer circumferential depressed portion and the other depressed portion in the central side to be lower than the pressure in a space between the outer circumferential depressed portion of the sample holder and the sample, and the pressure in a space between the other depressed portion in the central side and the sample.