| 摘要 |
PURPOSE:To enable the formation of a high resistance without prolonging a wiring by forming a wiring on a surface of a semiconductor substrate and electrically insulating or removing the surface of a predetermined part of the wiring. CONSTITUTION:After depositing polysilicon on an insulating film 6, phosphorus ion implantation, lithography, and etching are performed to form a desired polysilicon wiring 8. Next, at the same time as thermal diffusion of phosphorus ions in the polysilicon wiring 8, a thin oxide film 12 is formed on the polysilicon wiring 8. A silicon nitride film 13 is deposited and then the silicon nitride film 13 only of a high-resistance part of the polysilicon wiring 8 is removed by lithography and etching. A high-temperature oxide film 14 is formed on a part which is to be a high-resistance part by thermal oxidation. After removing the nitride film 13 and an oxide film 11, aresenic ions are implanted by using the high-temperature oxide film 14 as a mask to form a low-resistance part 11 by self-alignment. Thus, a high-resistance part can be formed even the part where an enough long wiring can not be arranged.
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