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Abstract

An adjustment method for photolithography. First, a semiconductor wafer is successively set in one of cell positions. In each of the cell positions, a laser beam is directed to the surface of the wafer and light reflecting off the wafer surface is detected and analyzed to determine a vertical offset position of the wafer at each cell position. Data representing the vertical offset position is stored in a memory and the process is repeated until the offset position data are derived from all cell positions. Thereafter, tilt angles of the wafer at all cell positions are determined from the stored offset position data, and angle data representing the determined tilt angles are stored in a memory. The wafer is then set in one of the cell positions, and the angle data is read from the memory corresponding to the set cell position and the wafer surface is horizontally aligned. The offset position data is read from the memory corresponding to the set cell position and the wafer surface is vertically moved to the focal point, and the process is repeated until the wafer is set to all cell positions.

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First Claim