Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To eliminate the necessity of excessive light etching which is performed before dry etching of polycrystalline semiconductor, by a method wherein the crystal grain diameter of a polycrystalline semiconductor film is specified by selectively eliminating an oxidation resistant film, a second semiconductor oxide film, and a part of the film thickness direction of the polycrystalline semiconductor film, and performing heat treatment. CONSTITUTION:After an SiO2 film 2 of, e. g. about 50mum in thickness is formed on the surface of an Si substrate 1 by thermal oxidation method, a polycrystalline Si film 3 of, e. g. about 480Angstrom in thickness is formed on the whole surface by, e. g. low pressure CVD method. By ionimplanting, e. g. Si, in the whole surface, the polycrystalline Si film 3 is turned into an amorphous state. One example of Si ion implantation condition is as follows; dosage is 1X10<15>cm<-2>, and energy is 40keV. After that, e. g. in a nitrogen (N2) atmosphere, heat treatment is performed at a low temperature of, e.g. about 700 deg.C for about 20 hours. By this heat treatment, the amorphous Si film formed by turning the ion-implanted polycrystalline Si film 3 into an amorphous state is subjected to solid-phase growth, and as the result, the polycrystalline Si film 3 whose crystal grain diameter is 0.5-10mum is formed.

Inventors

• 👤 Shinichi Ito
• 👤 信一 伊藤

Bibliographic Details