Elimination of low temperature ammonia salt in TiCl.sub.4 NH.sub.3 CVD reaction
US5271963A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1992 |
| Grant date | Dec 21, 1993 |
| Priority date | — |
| Expiry date | Nov 16, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C16/4405
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A cold wall CVD reactor, particularly one for use in depositing TiN in a TiCl.sub.4 +NH.sub.3 reaction, is provided with a metallic liner insert in partially thermally insulated from the reactor wall which serves as one plasma electrode to form a weak secondary plasma when energized along with a second electrode near the vacuum exhaust port of the reactor. The plasma, in cooperation with radiant lamps provided to heat a wafer substrate onto which the primary CVD film is to be applied, heats the liner and a portion of the space adjacent the reactor walls and susceptor surfaces downstream of the reaction volume to cause the formation of deposits to be of the nature that can be removed by plasma cleaning without opening the reactor volume. Deposits such as TiN.sub.x Cl.sub.y and TiN form at temperatures of approximately 200.degree. C. to 650.degree. C., preferably between 300.degree. C. and 450.degree. C., rather than adduct ammonia salts of TiCl.sub.4, which would tend to form at temperatures of 200.degree. C. or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.