Cobalt silicide structure for improving gate oxide integrity and method for fabricating same
US6281102A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 2000 |
| Grant date | Aug 28, 2001 |
| Priority date | — |
| Expiry date | Jan 13, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/28518
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An improved method is provided for fabricating a cobalt silicide structure that includes the steps of: (1) forming a silicon structure, wherein a native oxide is located over a first surface of the silicon structure, (2) loading the silicon structure into a chamber, (3) introducing a vacuum to the chamber, (4) depositing a titanium layer over the first surface of the silicon structure, wherein the thickness of the titanium layer is selected to remove substantially all of the native oxide, (5) depositing a cobalt layer over the titanium layer, (6) depositing an oxygen impervious cap layer over the cobalt layer; and then (7) breaking the vacuum in the chamber, and (8) subjecting the silicon structure, the titanium layer, the cobalt layer and the cap layer to an anneal, thereby forming the cobalt silicide structure. The cap layer can be, for example, titanium or titanium nitride. The resulting cobalt silicide structure is substantially free from oxygen (i.e., oxide). Consequently, an underlying gate oxide or substrate is advantageously protected from the effects of cobalt silicide spiking.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.