Semiconductor memory device and a method of manufacturing the same
US7981738B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 2010 |
| Grant date | Jul 19, 2011 |
| Priority date | — |
| Expiry date | Oct 22, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B10/12
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A memory cell of an SRAM has two drive MISFETs and two vertical MISFETs. The p channel vertical MISFETs are formed above the n channel drive MISFETs. The vertical MISFETs respectively mainly include a laminate formed of a lower semiconductor layer, intermediate semiconductor layer and upper semiconductor layer laminated in this sequence, a gate insulating film of silicon oxide formed on the surface of the side wall of the laminate, and a gate electrode formed so as to cover the side wall of the laminate. The vertical MISFETs are perfect depletion type MISFETs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.