| 摘要 |
PURPOSE:To simultaneously form the diffusion regions having varied depths using a simple process by a method wherein a diffusion source layer is provided on the semiconductor substrate whereon the insulating film, with a plurality of windows, has been covered through the intermediary of the buffer layer with the prescribed pattern, and a heat treatment is performed thereon. CONSTITUTION:The insulating film 2 having a plurality of windows is formed on a semiconductor substrate 1 such as an Si and the like, the buffer layer 5 consisting of a polycrystalline Si is provided thereon, the thickness of the buffer layer 5 on each window is varied by performing an etching, a diffusion source layer 7 such as a phosphor-silicic acid glass layer and the like is provided on the buffer layer 5, a heat treatment is performed, and diffusion regions 8 and 9 having varied depths are formed. Thus, as the diffusion regions having different depth is formed simultaneously by a simple method, the semiconductor elements having different characteristics of breakdown voltage and current amplification factor can be made simultaneously.
|
