Multi-layer collector heterojunction transistor
US5572049A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 1995 |
| Grant date | Nov 5, 1996 |
| Priority date | — |
| Expiry date | Apr 14, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/137
Abstract
A multi-layer collector heterojunction transistor (10) provides for high power, high efficiency transistor amplifier operation, especially in the RF (radio frequency) range of operation. A larger band gap first collector layer (12), approximately 15% of the active collector region (11) thickness, is provided at the base-collector junction (13). A smaller band gap second collector layer (14) forms the remainder of the active collector region (11). The multi-layer collector structure provides higher reverse bias breakdown voltage and higher carrier mobility during relevant portions of the output signal swing. A lower saturation voltage limit, or "knee" voltage, is provided at the operating points where linear operating regions transition to saturation operating regions as depicted in the output voltage-current (I-V) characteristic curves. The magnitude of the output signal swing of an amplifier may be increased, providing higher power amplification with greater power efficiency. The power supply voltage for the amplifier may be increased, providing for the use of a smaller, lighter power supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.