发明名称 |
Erasable and programmable nonvolatile semiconductor memory, semiconductor integrated circuit device having the semiconductor memory and method of manufacturing the semiconductor memory |
摘要 |
A nonvolatile semiconductor memory has memory cells (1) each having an insulated-gate FET that has an information storage part. A semiconductor region (27) is formed at the surface of a channel region of each memory cell. The semiconductor region has the same conductivity type as a channel conductivity type and functions to decrease the strength of an electric field at the surface of the channel region. If the insulated-gate FET is of an n-channel type, the semiconductor region is of an n-type. The semiconductor region suppresses threshold voltage variations among the insulated-gate FETs of the memory cells and prevents soft-writing in the memory cells.
|
申请公布号 |
US6222224(B1) |
申请公布日期 |
2001.04.24 |
申请号 |
US19970994482 |
申请日期 |
1997.12.19 |
申请人 |
KABUSHIKI KAISHA TOSHIBA |
发明人 |
SHIGYO NAOYUKI |
分类号 |
G11C11/56;G11C16/04;H01L21/8247;H01L27/115;H01L29/788;H01L29/792;(IPC1-7):H01L29/788 |
主分类号 |
G11C11/56 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|