SAMPLE STAGE

PURPOSE:To enable a great many small paths to be made with slight processing so as to reduce the cost of mechanical processing such as cutting, etc., by providing a fluid path consisting of porous material inside the mounting face of a sample. CONSTITUTION:A wafer table 20 forms three-layer structure of wafer tables 20a, 20b and 20c made of ceramic material. Groove parts are provided at the upper face of the wafer table 20a and at the lower face of the wafer table 20b, and a path 21 through which constant-temperature fluid flows and supply paths 22a and 23a for the constant temperature fluid are formed. The path 21 is filled with porous ceramic material, and this is formed zigzag over the whole face of the mounting face of the sample. Since the path 21 of the constant-temperature air to control the temperature of the wafer table 20 is made of the porous ceramic material this way, a great many small paths can be made with slight processing, and the cost of mechanical processing such as cutting, etc., can be reduced.