发明名称 |
Method for device ruggedness improvement and on-resistance reduction for power MOSFET achieved by novel source contact structure |
摘要 |
The invention discloses method for fabricating a MOSFET on a substrate to improve device ruggedness. The method includes steps of: (a) forming an epi-layer of a first conductivity type as a drain region on the substrate and growing an initial oxide layer over the epi-layer; (b) applying an active mask for etching the active layer to define an active area followed by depositing an overlaying polysilicon layer and applying a polysilicon mask for etching the polysilicon layer to define a plurality of polysilicon gates; (c) removing the mask and carrying out a body implant of a second conductivity type followed by performing a body diffusion for forming a plurality of body regions; (d) applying a source blocking mask for implanting a plurality of source regions in the body regions with ions of the first conductivity type followed by removing the blocking mask and a source diffusion process; (e) forming an overlying insulation layer covering the MOSFET followed by applying a contact mask to open a plurality of contact openings; (f) performing a low energy body-dopant and high energy body dopant implant to form a shallow high-concentration body dopant and a deep high-concentration body dopant region followed by applying a high temperature process for densification of the insulation layer and activating diffusion of the deep and shallow body dopant regions wherein the deep high-concentration body-dopant regions are formed below the source regions and extends beyond the contact regions but are kept at lateral distance away from a channel region of the MOSFET in the body region whereby device ruggedness is improved without increasing threshold voltage.
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申请公布号 |
US5930630(A) |
申请公布日期 |
1999.07.27 |
申请号 |
US19970899186 |
申请日期 |
1997.07.23 |
申请人 |
MEGAMOS CORPORATION |
发明人 |
HSHIEH, FWU-IUAN;SO, KONG CHONG;NIM, DANNY CHI |
分类号 |
H01L21/265;H01L21/336;H01L29/06;H01L29/10;H01L29/78;(IPC1-7):H01L21/336 |
主分类号 |
H01L21/265 |
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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