| 摘要 |
PURPOSE:To enable patterning through etching without reforming a photo-resist by using an upper layer metal as an etching resisting mask for a lower layer metal. CONSTITUTION:A P type base resion 2, an N type emitter region 3 and an N type collector contact region 4 are formed to an N type silicon wafer 1, the surface of the wafer is coated with an insulating film 5, and windows for contact are shaped. Platinum is evaporated and thermally treated and a platinum silicide 9 is formed, and platinum on the insulating film 5 is removed. A W (tungsten) layer 10 as a diffusion barrier metal and an Al layer 11 as a wiring metal are shaped. The Al layer is dry-etched using the photo-resists 12 as masks while the photo-resists 12 are also removed. W is etched employing Al as masks while using an etching agent (such as CF4 gas) which etches W but does not etch Al. |
