Abstract
The liquid-phase chemical-enhanced oxidation technique has been demonstrated to be an effective means of growing stable native films on GaAs. The gallium-ion-containing solution results in a fairly high oxidation rate near room temperature. The pH value of the oxidation solution appears to be a dominant factor in the kinetics of oxidation. Due to the enhancement of Ga-containing cations in the solution, a window of initial pH values from approximately 4.0 to 4.5 is found to be the optimum pH range for oxide growth. The pH-incorporated mechanism provides consistent interpretations for the unusual experimental results such as etchback of oxide thickness and increase of refractive index. In addition, the results of the pH-controlled procedure confirms the proposed role of pH. According to secondary ion mass spectroscopy profiles, it is found that the increasing As/Ga ratio of the oxide film contributes to the increase of oxide refractive index.
Original language | English |
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Pages (from-to) | 2328-2332 |
Number of pages | 5 |
Journal | Journal of the Electrochemical Society |
Volume | 146 |
Issue number | 6 |
DOIs | |
Publication status | Published - 1999 Jun |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Electrochemistry
- Materials Chemistry