Method of cleaning reaction tube and exhaustion piping system in heat processing apparatus
US5637153A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1995 |
| Grant date | Jun 10, 1997 |
| Priority date | — |
| Expiry date | Apr 26, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C16/4412
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
After a polysilicon film is formed on a wafer, a cleaning gas containing ClF.sub.3 at 10 to 50 vol % is supplied into a reaction tube and an exhaust pipe system at a flow rate of 3000 to 3500 SCCM, so as to remove a polysilicon-based film deposited on an inner wall surface of the reaction tube, the surface of a member incorporated in the reaction tube, and an inner wall surface of the exhaust pipe system while the film forming process, by etching using ClF.sub.3. The cleaning gas is supplied while the temperature in the reaction tube is maintained at 450.degree. C. or higher, and in a pressure condition set at the maintained temperature such that an etching rate of the polysilicon-based film by the cleaning gas is higher than an etching rate of silicon which is the material of the reaction tube or the member incorporated in the reaction tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.