Bidirectional switch
US8450810B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 21, 2011 |
| Grant date | May 28, 2013 |
| Priority date | — |
| Expiry date | Sep 8, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/518
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An ON resistance of a bidirectional switch with a trench gate structure composed of two MOS transistors sharing a common drain is reduced. A plurality of trenches is formed in an N type well layer. Then a P type body layer is formed in every other column of the N type well layer interposed between a pair of the trenches. A first N+ type source layer and a second N+ type source layer are formed alternately in each of a plurality of the P type body layers. A first gate electrode is formed in each of a pair of the trenches interposing the first N+ type source layer, and a second gate electrode is formed in each of a pair of the trenches interposing the second N+ type source layer. A portion of the N type well layer interposed between a sidewall on an opposite side of the body layer of the trench in which the first gate electrode is formed and a sidewall on an opposite side of the body layer of the trench in which the second gate electrode is formed makes an N type drain layer serving as an electric field relaxation layer. A cross-sectional area of the N type drain layer makes a path of the ON current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.