Method for reducing silicided poly gate resistance for very small transistors
US5672544A · kind A · utility
Inventor
Key dates
| Filing date | Apr 22, 1996 |
| Grant date | Sep 30, 1997 |
| Priority date | — |
| Expiry date | Apr 22, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S257/90
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for reducing resistance in the fabrication of a silicided polysilicon gate for a very small transistor integrated circuit device is described. A polysilicon layer is deposited overlying a gate silicon oxide layer. The polysilicon and gate oxide layers are etched away where they are not covered by a mask to form a gate electrode. Ions are implanted to form source and drain regions within the semiconductor substrate using the gate electrode as a mask. A dielectric layer is deposited overlying the semiconductor substrate and the gate electrode. The dielectric layer is anisotropically etched to leave first spacers on the sidewalls of the gate electrode. The first spacers are isotropically etched back to leave second spacers extending approximately halfway up on the sidewalls of the gate electrode. A layer of titanium is conformally deposited over the surfaces of the substrate. The substrate is annealed whereby the titanium layer is transformed into a titanium silicide layer. The unreacted titanium on the oxide spacers is etched back to leave the titanium silicide layer only on the top surface and the sidewalls of the gate electrode not covered by the second spacers and overlyi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.