发明名称 |
Method of making a field effect trench transistor having lightly doped epitaxial region on the surface portion thereof |
摘要 |
A DMOS field effect transistor having its gate electrode located in a trench includes a lightly doped epitaxial layer overlying the usual epitaxial layer. The trench penetrates only part way through the upper epitaxial layer which is more lightly doped than is the underlying lower epitaxial layer. The lightly doped upper epitaxial layer reduces the electric field at the bottom of the trench, thus protecting the gate oxide from breakdown during high voltage operation. Advantageously the upper portion of the lightly doped upper epitaxial layer has little adverse effect on the transistor's on resistance.
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申请公布号 |
US5532179(A) |
申请公布日期 |
1996.07.02 |
申请号 |
US19950447484 |
申请日期 |
1995.05.23 |
申请人 |
SILICONIX INCORPORATED |
发明人 |
CHANG, MIKE F.;HSHIEH, FWU-IUAN;KWAN, SZE-HON;OWYANG, KING |
分类号 |
H01L21/336;H01L29/08;H01L29/423;H01L29/78;(IPC1-7):H01L21/335;H01L21/20 |
主分类号 |
H01L21/336 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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