Semiconductor device and method for manufacturing the same
US6469345B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 2001 |
| Grant date | Oct 22, 2002 |
| Priority date | — |
| Expiry date | Jan 12, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/681
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A trench-gate type transistor has a gate insulating film formed on an inner wall of a trench. The gate insulating film is composed of a first portion disposed on a side wall portion of the trench and a second portion disposed on upper and bottom portions of the trench. The first portion is composed of a first oxide film, a nitride film, and a second oxide film. The second portion is composed of only an oxide film and has a thickness thicker than that of the first portion. Accordingly, electric field concentration on upper and lower corner portions of the trench can be mitigated, and a decrease in withstand voltage at that portions can be prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.