摘要 |
In vacuum sputter cleaning and plating operations forming a patterned metallic layer on a silicon semiconductor chip, alignment is maintained by anticipating the difference in thermal expansion between the molybdenum mask and the silicon chip and forming the apertures in the molybdenum mask in a radially offset position with respect to the intended cleaning and deposition locations on the semiconductor chip, when the mask and the chip are at room temperature. Then, when the mask and the silicon chip are maintained in a concentric position and are raised to the cleaning and deposition temperature, the differential expansion of the molybdenum mask will bring the apertures therein into perfect alignment with the intended deposition locations on the silicon wafer. |