发明名称 |
Method for making recessed field oxide for radiation hardened microelectronics |
摘要 |
A method of forming a recessed electrically-insulating field oxide region in a semiconductor substrate is disclosed. In a preferred embodiment, the method includes the steps of oxidizing a surface of the substrate; depositing a polysilicon layer over the oxide layer; depositing a silicon nitride layer over the polysilicon layer; patterning the silicon nitride and polysilicon layers and etching away both layers where the field oxide is to be located; forming a field oxide by thermally oxidizing the substrate in the openings previously formed in the silicon nitride and polysilicon layers; etching away the thermal field oxide; thermally oxidizing the substrate in the etched-away field oxide areas; etching away the silicon nitride layer; optionally, implanting through the thermal oxide with an impurity; depositing a doped oxide; densifying the oxide in a steam ambient; etching back the deposited oxide; then either depositing an undoped CVD oxide, coating the oxide with a leveling layer to planarize the oxide surface, etching both the undoped CVD oxide and leveling layers and etching away the polysilicon; or etching away the polysilicon, leaching the dopants out of the surface of the field oxide structure and passivating the surface in a dry oxygen ambient.
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申请公布号 |
US6063690(A) |
申请公布日期 |
2000.05.16 |
申请号 |
US19970999476 |
申请日期 |
1997.12.29 |
申请人 |
UTMC MICROELECTRONICS SYSTEMS INC. |
发明人 |
WOODRUFF, RICHARD L.;KERWIN, DAVID B.;CHAFFEE, JOHN T. |
分类号 |
H01L21/762;(IPC1-7):H01L21/76 |
主分类号 |
H01L21/762 |
代理机构 |
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地址 |
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