Semiconductor device having a region doped to a level exceeding the solubility limit
US5518937A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 1995 |
| Grant date | May 21, 1996 |
| Priority date | — |
| Expiry date | Mar 20, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/83
Abstract
A bipolar transistor includes a base region made of silicon crystal doped with a first impurity to a first level so as to establish a first carrier concentration in the base region and an emitter region made of silicon crystal doped with a second impurity to a second level substantially larger than the first level by a predetermined factor so as to establish a second carrier concentration in the emitter region, in which the second impurity exceeds the solubility limit of the second impurity in silicon crystal. The first and second levels are chosen in such a range that a difference in the carrier concentrations between the emitter region and the base region decreases substantially with increasing impurity level in the base region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.