| 摘要 |
PURPOSE:To realize a fine structure and, simultaneously, a steep junction with self- matching by simultaneously forming a single crystal semiconductor and a polycrystalline semiconductor on a semiconductor layer and an insulating layer respectively, and forming one part of the polycrystalline semiconductor as an electrode of the single crystal semiconductor. CONSTITUTION:After a thermal oxidation film pattern and a LPCVD nitride film pattern are formed on a P (111) substrate 11, an N<+> type buried layer 12 is formed and the patterns are removed, a N type epitaxial layer 13 is formed by a reduced pressure epitaxial method, and next an emitter-collector pattern using a thin oxide film and nitride film is again formed to carry out high pressure oxidation. In this time, an oxide film 15 is formed with its surface made substantially flat. The oxide and nitride film pattern 14 forming collector contact is left to remain and selective epitaxial growth is carried out on the said pattern under a low temperature. A single crystal layer of good quality is formed on an opening in the N type epitaxial layer 13, that is, a single crystal and a polycrystalline layer 18 is formed on the insulating film 15 except the said opening. Next, when the polycrystalline layer 18 is etched by fluoronitrate acetic acid solution, the polycrystalline layer 18 connected to a P type epitaxial layer 16 can be formed. |
