| 摘要 |
PURPOSE:To eliminate the variation of the thickness of an adhesive layer so as to maintain the excellent parallelism of a silicon wafer by providing air intake holes communicating with a vacuum system through a holding tool for polishing the silicon wafer and sucking and holding the wafer via an adhesive. CONSTITUTION:A wafer holding tool 11 is provided with, on its upper surface 11a, air intake holes 12 communicating with a vacuum system. This air intake holes 12 open, via a pressure reducing guide passage 13, only to parts on which wafers 2 are placed. This intake hole 12 is sized into, as one example, 1mm. in its diameter and 5-10mm. in distances among respective holes. This wafer holding tool is formed by, for example, aluminium or its alloy, and stainless and the like, and after sufficiently cleaning its surface, it is heated on a hot plate to the softening temperature of an adhesive, e.g., to 100 deg.C. Then, a paraffin series adhesive is applied on a part holding the wafer 2, and after the cleaned wafer 2 is placed thereon, it is adsorbed to said wafer holding part due to pressure reduction via the air intake hole 12 for about 3sec. Hereby, an 1mum thick adhesive layer 14 is formed. Then, it is transferred onto a cooling plate for its cooling to permit the adhesive to be solidified. |
