发明名称 |
Programming and erasing structure for an NVM cell |
摘要 |
A non-volatile memory (NVM) has a silicon germanium (SiGe) drain that is progressively more heavily doped toward the surface of the substrate. The substrate is preferably silicon and the drain is formed by first forming a cavity in the substrate in the drain location. SiGe is epitaxially grown in the cavity with an increasing doping level. Thus, the PN junction between the substrate and the drain is lightly doped on both the P and N side. The drain progressively becomes more heavily doped until the maximum desired doping level is reached, and the remaining portion of the SiGe drain is doped at this maximum desired level. As a further enhancement, the perimeter of the SiGe in the substrate is the same conductivity type as that of the substrate and channel. Thus a portion of the channel is in the SiGe.
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申请公布号 |
US7105395(B2) |
申请公布日期 |
2006.09.12 |
申请号 |
US20040930891 |
申请日期 |
2004.08.31 |
申请人 |
FREESCALE SEMICONDUCTOR, INC. |
发明人 |
BURNETT JAMES DAVID;CHINDALORE GOWRISHANKAR L.;SWIFT CRAIG T.;MURALIDHAR RAMACHANDRAN |
分类号 |
H01L29/72 |
主分类号 |
H01L29/72 |
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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