Low resistivity tungsten silicon composite film
US4851295A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 4, 1986 |
| Grant date | Jul 25, 1989 |
| Priority date | — |
| Expiry date | Nov 4, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1284
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A composite film is provided which has a first layer of WSi.sub.x, where x is greater than 2, over which is disposed a second layer of a tungsten complex consisting substantially of tungsten with a small amount of silicon therein, typically less than 5%. Both layers are deposited in situ in a cold wall chemical vapor deposition chamber at a substrate temperature of between 500.degree. and 550.degree. C.. Before initiating the deposition process for these first and second layers, the substrate onto which they are to be deposited is first plasma etched with NF.sub.3 as the reactant gas, then with H.sub.2 as the reactant gas, both steps being performed at approximately 100 to 200 volts self-bias. WSi.sub.x is then deposited onto the surface of the substrate using a gas flow rate for silane which is 20 to 80 times the flow rate of tungsten silicide, followed by deposition of a tungsten complex as the second layer, using a gas flow rate for tungsten hexafluoride which is 1 to 3 times the flow rate of silane, and a gas flow rate of hydrogen which is about 10 times the flow rate of silane. Similarly, in another embodiment, the tungsten complex without the silicide layer is deposited direc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.