Method of fabricating high emitter efficiency semiconductor device with low base resistance by selective diffusion of base impurities
Abstract
Abstract A transistor, such as NPN type, for example, is fabricated by first diffusing a heavily doped P-type base contact region into an N-type semiconductor layer epitaxially grown on a heavily doped N-type semiconductor wafer. Holes are etched through the base contact region into the N-type layer and strongly N-type semiconductor material containing both N-type impurities and faster diffusing P-type impurities is epitaxially grown so as to fill the holes. The wafer is then heated to diffuse the P-type impurities so as to form a base region of controlled thickness, simultaneously forming emitter-base and base-collector junctions. Emitter contact is made by contacting the material epitaxially grown in the holes. Other type semiconductor devices, such as semiconductor controlled rectifiers, may also be fabricated in this manner.
Inventors
- 👤 W Engeler
- 👤 M Garfinkel
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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