Stacked poly/amorphous silicon gate giving low sheet resistance silicide film at submicron linewidths
US6107147A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 1999 |
| Grant date | Aug 22, 2000 |
| Priority date | — |
| Expiry date | Dec 2, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/663
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of forming a poly-silicide gate electrode (102). The polysilicon deposition is broken into two steps. After the first polysilicon layer (102a) is formed, a very thin oxide (102b) is formed thereover. Polysilicon deposition then continues to form a second polysilicon layer (102c). The oxide layer (102b) inhibits grain growth resulting in a smaller grain size for the second polysilicon layer (102c). Prior to silicide formation, a pre-amorphization implant is performed to amorphize the second polysilicon layer (102c) and possibly some of the first polysilicon layer (102a) as well. Titanium is deposited and reacted with the polysilicon layers to form a silicide. The silicide process consumes the interface between polysilicon layers (102a & 102c) and possibly a portion of the first polysilicon layer (102a). The resulting silicide layer has a more uniform sheet resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.