Permeable base transistor having an electrode configuration for heat dissipation
US5155561A · kind A · utility
34Cited by
7References
35Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1988 |
| Grant date | Oct 13, 1992 |
| Priority date | — |
| Expiry date | Jan 5, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/85
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The base layer of a power permeable base transistor is formed as comb structures with grating teeth of the combs extending into active regions of semiconductor material. Extended active regions are separated by inactive regions over which collector contacts extend. Large devices have digitated base layers. The comb structures are fabricated by sputtering a uniform layer of tungsten and forming a nickel mask over the tungsten by both X-ray and photolithography techniques. The tungsten exposed by the nickel mask is then etched to leave the comb structures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.