发明名称 |
ISOLATION WITH OFFSET DEEP WELL IMPLANTS |
摘要 |
A method implants impurities into well regions of transistors. The method prepares a first mask over a substrate and performs a first shallow well implant through the first mask to implant first-type impurities to a first depth of the substrate. The first mask is removed and a second mask is prepared over the substrate. The method performs a second shallow well implant through the second mask to implant second-type impurities to the first depth of the substrate and then removes the second mask. A third mask is prepared over the substrate. The third mask has openings smaller than openings in the first mask and the second mask. A first deep well implant is performed through the third mask to implant the first-type impurities to a second depth of the substrate, the second depth of the substrate being greater than the first depth of the substrate. The third mask is removed and a fourth mask is prepared over the substrate, the fourth mask has openings smaller than the openings in the first mask and the second mask. Then, a second deep well implant is performed through the fourth mask to implant the second-type impurities to the second depth of the substrate.
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申请公布号 |
US2010289082(A1) |
申请公布日期 |
2010.11.18 |
申请号 |
US20090464206 |
申请日期 |
2009.05.12 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
ADKISSON JAMES W.;BRYANT ANDRES;JAFFE MARK D.;LOISEAU ALAIN |
分类号 |
H01L27/088;H01L21/266;H01L21/8234 |
主分类号 |
H01L27/088 |
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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