Process for forming a transistor with a nonuniformly doped channel
US5741736A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 1996 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | May 13, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/944
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor device (83)including a transistor (85) with a nonuniformly doped channel region can be formed with a relatively simple process without having to use high dose implants or additional heat cycles. In one embodiment, a polysilicon layer (14) and silicon nitride layer (16) are patterned at the minimum resolution limit. The polysilicon layer is then isotropically etched to form a winged gate structure (32). A selective channel implant step is performed where ions are implanted through at least one of the nitride wings of the winged gate structure (32) but are not implanted through the polysilicon layer (14). Another polysilicon layer (64)is conformally deposited and etched such that the polysilicon (74) does not extend beyond the edges of the nitride wings.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.