发明名称 |
Masking scheme for silicon dioxide mesa formation |
摘要 |
An improved masking stack (63) comprises a pad oxide (58), polysilicon (60) and nitride (62). After forming a photoresist pattern (64) over the stack (63), an anisotropic etch is performed to remove the nitride (62) and a portion of the polysilicon (60) not covered by the pattern (64). Another etch is performed to remove the remaining polysilicon (60) to leave at least a portion of the pad oxide (58). A boron implant (66) is conducted to form implant areas (68 and 70) within the unmasked silicon active device layer (56). A portion of the implant areas (68 and 70) is masked with nitride (72), and the unmasked silicon layer (56) is then etched. The masking stack (63) and the nitride (72) is removed and unprotected silicon layer (56) and implant areas (68 and 70) are covered with an oxide forming the silicon dioxide mesa (78).
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申请公布号 |
US4950618(A) |
申请公布日期 |
1990.08.21 |
申请号 |
US19890338719 |
申请日期 |
1989.04.14 |
申请人 |
TEXAS INSTRUMENTS, INCORPORATED |
发明人 |
SUNDARESAN, RAVISHANKAR;MATLOUBIAN, MISHEL |
分类号 |
H01L21/033;H01L21/266 |
主分类号 |
H01L21/033 |
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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