Abstract: Transferring device for a semiconductor wafer or like part includes a rotatable carrying arm rotatably for carrying a semiconductor wafer or part from its initial position and through a first angle. The rotatable carrying arm has a holding portion for a wafer or part, and a cam follower portion. A motor rotates the rotatable carrying arm through an angle slightly greater than the first angle slightly past a desired position for the wafer. Then, an eccentric cam returns the carrying arm through a second, incremental angle, for bringing the carrying arm, and, hence, the wafer held thereby, to the desired position.

Abstract: A wafer basket station includes a semiconductor wafer basket containing therein a number of semiconductor wafers and an elevating device which raises and lowers the wafer basket to bring a desired wafer in its taken out height. A wafer detecting device is formed with a transmission type optical sensor disposed inclined so that the optical axis thereof passes a center of a semiconductor wafer at the desired height, but not to pass adjacent wafers of the semiconductor wafer.The elevating device of the wafer basket has an elevator which supports wafers to be worked and treated and is guided and driven vertically with respect to a base frame of the device. The elevator is provided with an opaque body. A photocoupler support plate is guided to move vertically and supported with respect to the base frame of the device. A spring means is energized in the departing direction away from the photocoupler support plate against the base frame.