Process for the production of a bipolar integrated circuit
US4047975A · kind A · utility
20Cited by
9References
16Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 2, 1976 |
| Grant date | Sep 13, 1977 |
| Priority date | — |
| Expiry date | Jul 2, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/977
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of making a bipolar integrated circuit which requires neither an epitaxial layer nor a buried layer. The required doping of a semiconductor substrate, e.g., silicon, is obtained by a series of etching steps alternated with ion implantation steps of a selected impurity type, and heat treatment steps. The emitter and collector zones of a transistor are formed on sloping walls of adjacent troughs formed in a semiconductor substrate. The base zone of a transistor is formed on the confronting sloping wall of one of these troughs. Lead conductors are located in the troughs along sloping wall portions of the troughs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.