Study on the properties of gallium antimonide surface passivatied with S2Cl2 solution

The surface optical and chemical properties of gallium antimonide (GaSb) surfaces after dichloride disulfide (S₂Cl₂) and ammonium sulfide ((NH₄)₂S) treatments were compared. Photoluminescence (PL) spectroscopy is used to study the GaSb surfaces passivated by S₂Cl₂ comparing to (NH₄)₂S solution, meanwhile, quantitative comparison using x-ray photoelectron spectroscopy (XPS) demonstrates that S₂Cl₂ passivation dramatically improves the stability against reoxidation in air compared with the (NH₄)₂S solution. We found that S₂Cl₂ method is quite effective for removing oxides of GaSb surface, besides, PL intensity of S₂Cl₂-passivated sample was higher than (NH₄)₂S-passivated sample, and stability of S₂Cl₂-passivated sample was also more sustained. Overall, S₂Cl₂ provides to be superior passivation for III-V compound semiconductor material promising for high-speed and optoelectronic device applications.