Electrochemical Codeposition of InSb Thin Films on (100) GaAs Substrates*

InSb is a III-V semiconductor with notable properties including extremely high electron mobility and narrow bandgap. It has applications in infrared sensing, high-speed photodetectors, and thermophotovoltaics. Growth of InSb thin films on GaAs is difficult due to high lattice mismatch, but has been accomplished via techniques such as metalorganic vapor-phase epitaxy and molecular beam epitaxy. These methods, however, require costly specialized equipment, toxic precursor gases, or ultra-high vacuum.

In this study, we demonstrate the electrochemical deposition of polycrystalline InSb thin films on (100) GaAs substrates using aqueous electrolytes. This method is advantageous due to low cost and benchtop growth conditions. Dissolved precursor concentrations, applied bias voltages, and deposition times were varied. Additionally, the effect of elevated temperature on deposited films was investigated. Resulting films were characterized via Raman spectroscopy, X-ray diffraction, and FT-IR spectroscopy techniques.