| 摘要 |
PURPOSE:To simplify a production process, to lower the resistance of a wiring part and to reduce the resistance of connection to a device region and a lower-layer wiring part by a method wherein a refractory metal silicide film as an upper-layer wiring part is formed directly by sputtering and, in addition, impurities are diffused into the upper-layer wiring part of the refractory metal silicide film from a specific insulating film which covers the upper-layer wiring part from an upper layer and a lower layer. CONSTITUTION:A field insulating film 2, an N-type diffusion region 3 and a polycrystalline silicon film 4 containing phosphorus as a lower-layer wiring part are formed on a P-type Si substrate 1; a silicon oxide film (a PSG film) 5 containing 3-10 mol % of phosphorus is formed on the whole surface. Then, an opening is made at the PSG film 5 which is situated on the diffusion region 3 and the film 4; a titanium silicide film 6 is formed on the whole surface by a sputtering method; this film is etched selectively and an upper-layer wiring part is formed. Then, a PSG film 7 containing 3-10 mol % of phosphorus is formed on the whole surface; it is heat-treated; the phosphorus is diffused into the film 6 from the PSG films 5, 7; this film is connected to the diffusion region 3 and the film 4 at low resistance. By this setup, the production process is simplified and a low-resistance wiring part can be formed.
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