Method of fabricating bipolar transistors and insulated gate field effect transistors having doped polycrystalline silicon conductors
US4735916A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 1987 |
| Grant date | Apr 5, 1988 |
| Priority date | — |
| Expiry date | Feb 10, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/017
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of fabricating a semiconductor device includes the steps of: forming at least one first semiconductor region of a first conductivity type and at least one second semiconductor region of a second conductivity type in a main surface of a semiconductor layer of the first conductivity type; forming a three-layer film having a desired shape on each of the first and second semiconductor regions, the three-layer film being made up of a bottom layer which is a conductive film, an intermediate layer which is a silicon nitride film, and a top layer which is a polycrystalline silicon film doped with one of arsenic and phosphorus; forming a first insulating layer on the side wall of the three-layer film; forming a second polycrystalline silicon film on the whole surface, and diffusing one of arsenic and phosphorus from the first polycrystalline silicon film into the second polycrystalline silicon film; selectively etching off the first polycrystalline silicon film and that portion of the second polycrystalline silicon film, in which one of arsenic and phosphorus has been diffused; forming a second insulating layer at least on the surface of the portion of the second polycrystalline si…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.