Gallium antimonide (GaSb) has an extremely high electron mobility and an excellent lattice match with various III-V ternary and quaternary compounds. In this study, the effect of wet-etching processes on the GaSb (001) surface was investigated, with a focus on the effect of H2O2. Dilution with H2O and addition of H2O2 in HF/H2O2/H2O, NH4OH/H2O2/H2O, and HCl/H2O2/H2O mixtures produced different effects on the GaSb surface. The etching rate of GaSb increased with a high dilution ratio and a small amount of H2O2 in the mixture of NH4OH/H2O2/H2O. The addition of H2O2 in H2O decreased GaSb oxide thickness and increased the contact angle on the GaSb surface and the XPS Ga 3d and Sb 3d3/2 peak area ratios of Ga2O3/GaSb and Sb2O3/GaSb, which strongly imply that the H2O2 in the wet-etching solution served as an inhibitor of surface oxidation on GaSb. On the basis of the observed etching rates of GaSb, oxidation kinetics, contact angles, and chemical states, it is suggested that concurrent oxidation of GaSb and etching of oxidized GaSb occur on the GaSb surface in the presence of H2O2. Furthermore, the overall kinetics is determined by the relative amount of H2O2, which depends on the pH of the etching solution.
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© 2015 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films