| 摘要 |
<p>PURPOSE: To secure the flatness of a substrate with high accuracy without being influenced by foreign matter even if foreign matter such as rust, etc., of submicron size exist. CONSTITUTION: A holder 24 consists of many face elements 52, and a suction hole is made in each face element 52. Each face element 52 is constituted to be capable of being driven independently in vertical direction. Therefore, when a stage on which the holder 24 is provided shifts in two-dimensional direction in such condition that a wafer is retained on the holder 24, the flatness of the wafer is detected by an AF sensor or the like, and by moving each face element in vertical direction, according to the detection result of this flatness, the flatness of the wafer can be corrected separately for each section corresponding to the face element 52.</p> |
