Semiconductor device

Abstract

Abstract PURPOSE:To control current amplification factor of a vertical type pnp-transistor, by forming a p<+>-type buried-in layer on a p-type semiconductor substrate by ion injection, and adjusting the climbing of the p<+>-type buried-in layer when an n-type layer is grown on it. CONSTITUTION:A p<+>-type buried-in layer 2 is diffused by ion injection in p<+>- type Si substrate 1, which is to become a collector. An n-type epitaxial layer 3 is grown on the entire surface, and at the same time, p<+>-type climb layer 4 is formed by causing layer 2 to climb in layer 3. Next, following the usual transistor manufacturing process, V-groove 4 reaching substrate 1 is cut, and this is filled with polycrystalline Si layer 8. An n<+>-type base region 10 and p<+>-type emitter region 11 are formed by diffusion in island region 6 separated from layer 3, and thereby a vertical pnp-transistor is formed. In this structure, since the current amplification factor is determined by the thickness of layer 3, the depth of region 11 and the amount of climb h of layer 4, an optimum amplification factor can be obtained by adjusting the dose region of layer 2, and temperature and time of heat treatment.

Inventors

• 👤 Kazuo Tanaka

Bibliographic Details