| 摘要 |
The present invention relates to a membrane of a carrier head of a chemical mechanical polishing apparatus. The membrane comprises: a bottom plate which is formed of a flexible material; a lateral surface which is bent and formed at an edge of the bottom plate, is formed of a flexible material, and has a ring-shaped first buffer groove formed on the outer circumferential surface adjacent to the bottom plate; and an inner fixed element which is formed of a material having greater hardness than those of the lateral surface and the bottom plate, and is fixed on the upper inside of the first buffer groove. Accordingly, the ring-shaped first buffer groove is formed on the outer circumferential surface of the lateral surface of the membrane, pressurizing force transferred downward while a cross section is reduced at a position of the first buffer groove on a path taken along the lateral surface to which the pressurizing force is transferred; is not concentrated on the edge end of the wafer but is distributed, and thus it is possible to prevent the pressurizing force transferred to the edge of the wafer from being excessively raised. |
