Apparatus for cleaning semiconductor wafers

摘要

An apparatus for cleaning semiconductor wafers includes a tank for containing a liquid and receiving a wafer holder with at least a portion of the wafers immersed in the liquid in the tank. A sonic energy generator imparts sonic energy to the liquid. A wafer-moving mechanism in the tank reciprocates and rotates the semiconductor wafer so that at least a portion of the wafer repeatedly passes through an upper surface of the liquid. The wafer-moving mechanism comprises a camming mechanism rotatably received in the tank and a drive for rotating the camming mechanism about a fixed central longitudinal axis of the camming mechanism to reciprocate and rotate the wafer. The camming mechanism includes a cam body having opposing flats spaced apart on opposite sides of its longitudinal axis and opposing gripping surfaces extending between the flats. The cam body has a cross-section defining a major axis and a minor axis, with the major axis of the cam body cross-section being greater than the minor axis. The gripping surfaces have a circumferentially extending groove for receiving a peripheral edge of the semiconductor wafer therein. The groove is sized for gripping the edge of the wafer as the camming mechanism rotates thereby to inhibit slippage of the wafer relative to the camming mechanism and to maintain uniform rotation and reciprocation of the wafer.