| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a wafer holder in which presence of a wafer on the mounting surface can be confirmed well electrically with high reliability over a long term by improving the electrical conduction structure between the wafer mounting surface of a wafer holding member and an introduction tube. SOLUTION: The wafer holder comprises a ceramic wafer holding member 11 having a through hole 11c, a metallic introduction tube 12 having an upper end flange part 12a brazed to the periphery of the lower surface 11b side opening of the through hole 11c, and a ceramic ring 15 brazed to the flange part 12a while having a through hole of larger inside diameter than that of the through hole 11c and a beveled part 15a formed at the upper surface side opening of the through hole. The wafer holding member 11 is provided with a step part 11d at the lower surface 11b opening of the through hole 11c, and the inner side face 11e at the step part 11d extends within a range R from the upper surface side starting point P of the beveled part 15a to a position of 1.5 mm toward the central side and the vertical depth is 0.5-2.5 mm.</p> |
