Optimized tungsten contact plug process via use of furnace annealed barrier layers
US5705442A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 1995 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Oct 27, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76877
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process, to fill small diameter contact holes with tungsten, without deleterious attack of contact hole liner materials, during the tungsten deposition, has been developed. The process consists of using a titanium nitride barrier layer, overlying a titanium adhesive layer. However the barrier characteristics of titanium nitride are enhanced by subjecting this layer to an anneal cycle in an nitrogen ambient. The annealing produces a more robust barrier in terms of incorporating additional nitrogen into the deposited titanium nitride layer, as well as forming titanium nitride on any underlying titanium, that may be exposed due to defects in the deposited titanium nitride layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.