Optimisation of the ammonium sulphide (NH4)2S passivation process on In0.53Ga0.47As

▶ (NH4)2S passivation parameters investigated for optimal chemical passivation of InGaAs. ▶ XPS and AFM used to determine level of native oxide and surface roughness present. ▶ Variations in (NH4)2S concentration, treatment time, temperature and pre-treatment. ▶ 10% (NH4)2S for 20 min at room temperature provides optimal chemical passivation.