Bipolar transistor with enhanced base transport
US7566948B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 2004 |
| Grant date | Jul 28, 2009 |
| Priority date | — |
| Expiry date | Jun 25, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/177
Abstract
A bipolar transistor includes a base layer design and a method for fabricating such a bipolar transistor that employ a built-in accelerating field focused on a base region adjacent to a collector, where minority carrier transport is otherwise retarded. The accelerating field of the base layer includes on average, a relatively low p-doping level in a first region proximate to the collector and a relatively high p-doping level in a second region proximate to an emitter. Alternatively, the accelerating field can be derived from band gap grading, wherein the grade of band gap in the first region is greater than the grade of band gap in the second region, and the average band gap of the first region is lower than that of the second region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.