发明名称 |
Method of forming a surface implant region on a ROM cell using a PLDD implant |
摘要 |
The invention provides a method for forming a ROM cell surface implant region using a PLDD implant. A semiconductor structure is provided comprising a substrate having isolation structures thereon, which separate and electrically isolating a first area having a P-well formed in the substrate and a gate over the substrate, a second area having a N-well formed in the substrate and a gate over the substrate, and a third area having P-well and buried N+ regions formed in the substrate with second isolation structures overlying the buried N+ regions. A photoresist mask is formed exposing the first area, and impurity ions are implanted to form n-type lightly doped source and drain regions. The photoresist mask is removed and a new (PLDD/ROM) photoresist mask is formed exposing the second area and the third area. Impurity ions are implanted to simultaneously form p-type lightly doped source and drain regions and a ROM cell surface implant region region. The PLDD/ROM photoresist mask is then removed.
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申请公布号 |
US6297102(B1) |
申请公布日期 |
2001.10.02 |
申请号 |
US19990409874 |
申请日期 |
1999.10.01 |
申请人 |
TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY |
发明人 |
YOU JYH-CHENG;WU LIN-JUNE |
分类号 |
H01L21/8238;H01L27/118;(IPC1-7):H01L21/823 |
主分类号 |
H01L21/8238 |
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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