TWO STAGE PIN STRUCTURE OF WAFER STAGE AND WAFER LOADING METHOD

摘要

A two stage pin structure of a wafer stage and a wafer loading method are provided to reduce scrap of the wafer and to prevent a loading position of the wafer from being changed by forming a wafer loading pin contacted to a lower surface of the wafer with the two stage structure. Plural pinholes(33a) are formed on a wafer holder(33). A wafer(1) is loaded on an upper side of the wafer holder. A wafer loading pin(100) is comprised of an external pin(110) and an internal pin(120). The external pin passes through and is inserted into the pin hole of the wafer holder when the wafer is loaded. The internal pin is inserted into the external pin. A driving unit elevates the internal pin and the external pin upwardly and downwardly. A control unit transmits a driving signal to the driving unit to control an operation of the external pin. A lower end of the internal pin is supported by a buffer member(130) at which a vacuum passage(120a) is formed. The buffer member is made of a rubber material.