| 摘要 |
PURPOSE:To prevent deformation of the wafer, by providing one or plural convexes, whose top faces are not protruded from the stand face in grooves. CONSTITUTION:Plural grooves 18, 18' are provided on the upper face where the wafer is put in fixed stand 1. Sections along line A-A' of groove 18 and line B-B' of groove 18' are formed as shown in figures. Grooves 18, 18'... are widened radially from the center of the fixed stand toward the edge, and fan-shaped convexes 9, 9'... are provided near the outside edge in grooves. Top faces of convexes agree with the upper face of fixed stand 1 or are lower than it slightly. Thus, since grooves 18, 18'... of sufficiently large section areas which can eject gas rapidly are provided and convexes 9, 9'... to support the wafer are arranged in grooves, deformation of the wafer is prevented. |
