JPS5772379A - Manufacture of semiconductor devuce - Google Patents

Abstract

PURPOSE:To reduce a short-channel effect and parasitic capacity by giving a concentration profile not only in the diffusion depth direction but also in the lateral direction about source and drain regions. CONSTITUTION:Field oxide films 2 are formed onto a P type silicon substrate 1, and P<+> layers 3 for preventing field inversion are shaped under the films 2. When a silicon oxide film 7 is formed and the whole surface is etched, the silicon oxide films 7 are left in the inner circumferential sections of diffusion windows 6. As is diffused through an ion injection method, and N<+> diffusion layers 8 (81-83) functioning as a source, a drain and other wiring layers are shaped. The whole is thermally treated for activation, and the concentration profile in the lateral direction is obtained. A PSG film 9 is accumulated through a CVD method, contact holes are opened and the film is extracted, and electrodes 101, 102 are disposed.