发明名称 |
Non-uniform threshold voltage adjustment in flash eproms through gate work function alteration |
摘要 |
Aspects for forming a Flash EPROM cell with an adjustable threshold voltage are described. In a method aspect, the method includes forming a substrate structure to establish a foundation for cell formation, and forming a gate structure with a floating gate layer comprising polysilicon-germanium (poly-SiGe) of a non-uniform Ge concentration on the substrate structure. The method further includes forming source and drain regions within the substrate structure, the drain region having a different threshold voltage than the source region. In a further aspect, a Flash EPROM cell with an adjustable threshold voltage includes a substrate structure as a foundation for the cell. The cell further includes a gate structure on the substrate structure, the gate structure comprising a floating gate layer of polysilicon-germanium (poly-SiGe) of non-uniform Ge concentration. Additionally, source and drain regions are included in the substrate structure bordering the gate structure, the drain region having a differing threshold voltage than the source region.
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申请公布号 |
US5888867(A) |
申请公布日期 |
1999.03.30 |
申请号 |
US19980023241 |
申请日期 |
1998.02.13 |
申请人 |
ADVANCED MICRO DEVICES, INC. |
发明人 |
WANG, JANET;LUNING, SCOTT D.;CHAN, VEI-HAN;TRIPSAS, NICHOLAS H. |
分类号 |
H01L21/28;H01L21/3215;H01L21/336;H01L29/423;H01L29/49;(IPC1-7):H01L21/824 |
主分类号 |
H01L21/28 |
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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