FORMING METHOD FOR ALUMINUM WIRING

摘要

PURPOSE:To enable easy formation of aluminum wiring with a trapezoidal cross-sectional area, by performing silicon etching of a wafer so that its cross- sectional area is trapezoidal and next by using masks of a photoresist and an amorphous silicon film to perform aluminum etching of the wafer. CONSTITUTION:An amorphous silicon layer 4 is laminated on a wafer on which a silicon oxidizing film 2 and an aluminum film 1 are laminated, and a desired shape of a photoresist 5 is formed thereon. Next silicon etching of the wafer is performed so that a cross-sectional area of the amorphous silicon film 4 is trapezoidal. With the photoresist 5 and the amorphous silicon film 4 being used as masks, aluminum etching is performed by utilizing a feature that end parts of the masks are backed by etching them. Aluminum wiring with a trapezoidal cross-sectional area is formed by peeling the photoresist 5 and the amorphous silicon film 4 on the wafer.