Low-temperature in-situ dry cleaning process for semiconductor wafer
US5403434A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 6, 1994 |
| Grant date | Apr 4, 1995 |
| Priority date | — |
| Expiry date | Jan 6, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/906
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A low-temperature (350.degree. C. to 750.degree. C.) in-situ dry cleaning process for removing native oxide (and other contaminants) from a semiconductor wafer surface, that can be used with either batch or single-wafer semiconductor device manufacturing reactors. A wafer is contacted with a dry cleaning mixture of digermane Ge.sub.2 H.sub.6 and hydrogen gas (51). The digermane-to-hydrogen flow ratio is small enough (usually between 1 ppm to 100 ppm) to ensure effective wafer surface cleaning without any germination deposition. Moreover, the dry cleaning mixture can include a halogen-containing gas (such as HCl or HBr) (52, 54) to enhance removal of metallic contaminants, and/or anhydrous HF gas (53, 54) to further enhance the native oxide removal process. The dry cleaning process can be further activated by introducing some or all of the hydrogen and/or an inert additive gas as a remote plasma. The digermane-based cleaning process of this invention can also be further activated by photo enhancement effects. This dry cleaning process is adaptable as a precleaning step for multiprocessing applications that, during transitions between process steps, reduce thermal cycling (FIGS. 3a-c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.