Plasma processing apparatus and plasma processing method

Abstract

There is provided a means for uniformly controlling the in-plane temperature of a semiconductor wafer at high speed in a high heat input etching process. A refrigerant channel structure in a circular shape is formed in a sample stage. Due to a fact that a heat transfer coefficient of a refrigerant is largely changed from a refrigerant supply port to a refrigerant outlet port, the cross sections of the channel structure is structured so as to be increased from a first channel areas towards a second channel areas in order to make the heat transfer coefficient of the refrigerant constant in the refrigerant channel structure. Thereby, the heat transfer coefficient of the refrigerant is prevented from increasing by reducing the flow rate of the refrigerant at a dry degree area where the heat transfer coefficient of the refrigerant is increased. Further, the cross section of the channel structure is structured so as to be reduced from the second channel areas towards a third channel areas, and thereby the heat transfer coefficient of the refrigerant is prevented from decreasing. Accordingly, the heat transfer coefficient of the refrigerant can be uniformed in the channel structure.