Method for forming low resistance and low defect density tungsten contacts to silicon semiconductor wafer
US5250467A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1991 |
| Grant date | Oct 5, 1993 |
| Priority date | — |
| Expiry date | Mar 29, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/907
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An improved process is described for forming planar tungsten-filled contacts to a silicon substrate in contact openings through an insulating layer which provides for the formation of titanium silicide in and on the silicon surface at the bottom of the contact openings to provide low resistance silicide interconnections between the silicon substrate and the tungsten. A titanium nitride layer is formed over the titanium silicide and on the surfaces of the insulation layer, including the top surface of the insulation layer and the sidewall surfaces of the contact openings through the insulating layer. This titanium nitride layer provides a nucleation layer which permits a good bond to form from the tungsten through the titanium nitride and titanium silicide in the contact openings to the silicon substrate; and from the tungsten through the titanium nitride layer to the insulator material such as silicon dioxide (SO.sub.2), resulting in the formation of low resistance and low defect density contacts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.