JPS6459854A - Semiconductor device - Google Patents

Abstract

PURPOSE:To reduce the resistance of an electrode part, by employing a single crystal as the deriving electrode of a base. CONSTITUTION:After an N<+>type region 12 is formed in a part of the surface of a P-type silicon substrate 11, a silicon dioxide film 13 is formed thereon. Trenches 14 and 15 are then formed throughout the thickness of the silicon dioxide film 13 to expose a part of the silicon surface of the substrate 11. Next, the trenches 14 and 15 are respectively filled with selectively epitaxial silicon films 16 and 17 which are grown from the silicon of the substrate 11 as a seed crystal. Subsequently, the silicon film 17 is covered on the surface thereof with a silicon dioxide film 18, and boron ions 19 are thereafter implanted into the surface of the silicon film 16. Moreover, after a silicon film 20 is formed over the whole surface of the substrate body, an opening is formed on the part 16 of which the silicon is epitaxially grown. Subsequently, a silicon film 21 is selectively grown in the opening while N-type impurity of arsenic or the like is doped into the silicon film 21. Further, after a silicon dioxide 22 is formed over the whole surface of the substrate body, an opening is formed on the each of a base 23, an emitter 24 and a collector 25, and an aluminum metallization is thereafter performed.