Ion implantation to increase emitter energy gap in bipolar transistors
US4559696A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 1984 |
| Grant date | Dec 24, 1985 |
| Priority date | — |
| Expiry date | Jul 11, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/834
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The suppression of the reverse injection of the carriers in a bipolar transistor, without adversely effecting forward injection, is carried out by modifying the energy gap characteristics of the transistor so that a greater barrier to reverse injection is presented than that which is confronted by the forward injected carriers. The energy gap of the emitter is increased, relative to that of the base, through ion implantation. The ions which are implanted are such that the resulting compound material has a higher energy gap than that of silicon into which they are implanted to selectively modify the emitter region so as to locally increase its energy gap. Preferred materials include carbon and nitrogen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.