Low-temperature in-situ dry cleaning process for semiconductor wafers
US5089441A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 16, 1990 |
| Grant date | Feb 18, 1992 |
| Priority date | — |
| Expiry date | Apr 16, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/909
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A low-temperature (650.degree. C. to 800.degree. C.) in-situ dry cleaning process (FIG. 2) for removing native oxide (and other contaminants) from a semiconductor surface can be used with either multi-wafer or single-wafer semiconductor device manufacturing reactors. A wafer is contacted with a dry cleaning mixture of germane GeH.sub.4 and hydrogen gas (51), such that the germane:hydrogen flow ratio is less than about 0.15:12000 sccm. The dry cleaning mixture can include a halogen-containing gas (such as HCl or HBr) (52, 54) to enhance cleaning of metallic contaminants, and/or anhydrous HF gas (53, 54) to further lower the process temperature. The dry cleaning process can be achieved by introducing some or all of the hydrogen and/or an inert gas as a remote plasma. The dry cleaning process is adaptable as a precleaning step for multiprocessing methodologies that, during transitions between process steps, reduce thermal cycling (FIGS. 3c-3e) by reducing wafer temperature only to an idle temperature (350.degree. C.), and by reducing vacuum cycling by maintaining flow rates for constant gases (FIG. 3c), thereby substantially reducing thermal stress and adsorption of residual impuritie…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.