Manufacture of insulated gate field effect transistor

Abstract

Abstract PURPOSE:To particularly form a double diffused MOSFET in a short time by forming while controlling an accelerating voltage and an impurity density when forming a reverse conductivity type base region, and the first conductivity type emitter region by implanting second conductivity type impurity ion on the first conductivity type semiconductor substrate, thereby performing thermal oxidizing process only once. CONSTITUTION:A thick field oxide film 2 is formed on the peripheral edge of the surface of an N<-> type Si substrate 1 to become a drain, a resist 3 made of a laminated layer film of Au, Cr is coated on the entire surface which includes the film, a window is opened corresponding to the center of a base region, and a P<+> type implanted region 4 is formed by ion implanting at high speed in high density to the deep portion in the substrate 1. Then, the resist 3 is removed, ions are implanted at a high speed in the density for obtaining the prescribed threshold value in a region surrounded by the film 2 on the region 4 to form a shallow P-type region 5, a resist 6 is formed by revising corresponding to the region 4, and an N<+> type source region 7 is formed by ion implanting at high speed in high density in the region 5 of both sides. Thereafter, the regions are diffused by heat treating, and electrodes are provided on the prescribed region.

Inventors

• 👤 Koichi Yamada
• 👤 耕一 山田

Bibliographic Details