Heterojunction semiconductor device and method of manufacturing
US7915640B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 19, 2006 |
| Grant date | Mar 29, 2011 |
| Priority date | — |
| Expiry date | Jan 23, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/85
Abstract
A metamorphic buffer layer is formed on a semi-insulating substrate by an epitaxial growth method, a collector layer, a base layer, an emitter layer and an emitter cap layer are sequentially laminated on the metamorphic buffer layer, and a collector electrode is provided in contact with an upper layer of the metamorphic buffer layer. The metamorphic buffer layer is doped with an impurity, in a concentration equivalent to or higher than that in a conventional sub-collector layer, by an impurity doping process during crystal growth so that the metamorphic buffer layer will be able to play the role of guiding the collector current to the collector electrode. Since the sub-collector layer, which is often formed of a ternary mixed crystal or the like having a high thermal resistance, can be omitted, the heat generated in the semiconductor device can be rapidly released into the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.