JPS57207373A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To obtain an MOS type FET having high threshold voltage by laminating and forming polycrystal Si containing an impurity and a silicide layer onto a gate oxide film with an opening, boring an opening to the silicide layer and thermally treating the silicide layer when source and drain regions are shaped into a semiconductor substrate. CONSTITUTION:A thick field oxide film32 is formed to the end section of an Si substrate 31, the substrate 31 surrounded by the film 32 is coated with a thin gate oxide film 33, and the openings are bored while being made correspond to the source and drain regions. The polycrystal Si film 34 containing P is grown to the whole surface containing the films 32, 33, and the film 34 is coated with the Mo silicide film 35. The film 35 is patterned and only sections which must function as gate electrode wiring and source and drain layer wiring are left, and the films 34 of sections exposed are changed into oxide films through heat treatment in an oxidizing atmosphere while the P in the film 34 is diffused and the source and drain regions 36 are shaped. Accordingly, the silicide film 35' on the film 33 is used as a gate electrode and the films 35'' extending onto the film 32 from the regions 36 as source and drain wiring respectively.