NEGATIVE-ION ASSISTED SILICON OXIDATION IN DOWNSTREAM OF MICROWAVE PLASMA

Citation
T. Koromogawa et al., NEGATIVE-ION ASSISTED SILICON OXIDATION IN DOWNSTREAM OF MICROWAVE PLASMA, JPN J A P 1, 37(9A), 1998, pp. 5028-5032
Citations number
8
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics, Applied
Volume
37
Issue
9A
Year of publication
1998
Pages
5028 - 5032
Database
ISI
SICI code
0021-4922(1998)37:9A<5028:NASOID>2.0.ZU;2-7
Abstract
For one application of negative ions in plasma, silicon oxidation at l ow temperatures was studied by employing the oxygen negative ions. In the downstream region of microwave oxygen plasma, the silicon oxidatio n was examined under DC bias. The oxidation depth was much larger unde r the positive bias than under the negative. It was found that the oxi dation depth became maximum at a certain distance in downstream, and t his was consistent with the distance at which the probe saturation cur rent ratio showed a local minimum, suggesting a maximum negative ion d ensity at that point. An in-depth analysis by X-ray photoelectron spec troscopy (XPS) showed that the oxidation proceeded almost lineally wit h the substrate bias voltage, and this voltage dependence was also fou nd for the Si substrate at a temperature of 200 degrees C. The repetit ion of the short time application of the substrate bias was found to b e effective for further oxidation.