The Defect Density Of A Sin_x/in_(0.53)ga_(0.47)as Interface Passivated Using (nh_4)_2s_x

摘要

Passivation of the electronic defect states at a SiN_x/InGaAs interface has been achieved using (NH_4)_2S_x treatments of the InGaAs surface. The X-ray photoelectron spectroscopy technique was used to investigate the mechanism of sulfur passivation. The results indicate that sulfur treatment can effectively erase the native oxides, and S-In, S-Ga and S-As bondings are formed after sulfidation. The fabrication of Au/SiN_x/InGaAs metal-insulator-semiconductor diodes has been achieved by depositing a layer of SiN_x on (NH_4)_2S_x-treated n-InGaAs using the plasma enhanced chemical vapor deposition technique. The effect of passivation on the InGaAs surface before and after annealing was evaluated by current-voltage and capacitance-voltage measurements. The results indicate that the SiN_x passivation layer exhibits good insulative properties. The annealing contributes to the decrease of the fixed charge density and the minimum surface state density, which are 4.5 × 10~(11) cm~(-2) and 3.92 × 10~(11) cm~(-2) eV~(-1), respectively. A 256 × 1 InP/InGaAs/InP heterojunction short-wavelength infrared detector, fabricated with the sulfidation plus a SiN_x passivation layer, has shown a good response uniformity of 4.81%.