METHOD FOR FABRICATING SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating a semiconductor device is provided to suppress an increase of a concave portion in a copper alloy layer induced by a polishing when forming a buried wiring of a copper alloy in a groove. CONSTITUTION: In a method for fabricating a semiconductor device, grooves for a wiring a reformed in an insulation layer(11) which is formed on a wiring substrate(10). A lower metal layer(12) and an upper metal layer(13) are sequentially formed on the insulation layer(11) comprising the grooves. The upper metal layer(13) is polished, and then the lower metal layer(12) is polished in a polishing speed five times more speedy than that of the upper metal layer(13).