JPS6448457A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To omit an etching process difficult to be controlled by a method wherein silicon is patterned to a specific shape by using a single mask, the single crystal and polycrystal of silicon are grown simultaneously, a post composed of silicon dioxide is removed, and a recessed section is formed in an intrinsic base forming region. CONSTITUTION:Silicon dioxide is patterned to a shape that there is a pots consisting of an silicon dioxide layer 7 at a central section, an intrinsic base region, on one conductivity type silicon layer 1, the n-type silicon layer 1 is exposed to an external base region and an silicon nitride layer 3 is laminated onto an silicon dioxide layer 2 in a region surrounding the external base region by employing a single mask. A single crystal silicon layer 9 and a polycrystalline silicon layer 10 are shaped respectively by executing the single crystal and polycrystal simultaneous growth method of silicon, and lastly the post made up of silicon dioxide 7 is removed, thus forming the intrinsic base forming region. Accordingly, only one alignment mask is sufficient, and an etching process difficult to be controlled is omitted.