The effect of nitridation and sulfur passivation for In0.53Ga0.47As surfaces on their Al/Al2O3/InGaAs MOS capacitors properties*

The impact of nitridation and sulfur passivation for In0.53Ga0.47As surfaces on the Al/Al2O3/InGaAs MOS capacitors properties was investigated by comparing the characteristics of frequency dispersion and hysteresis, calculating the D-it and Delta N-bt values, and analyzing the interface traps and the leakage current. The results showed that both of the methods could form a passivation-layer on the InGaAs surface. The samples treated by N-2 plasma could obtain good interface properties with the smallest frequency dispersion in the accumulation region, and the best hysteresis characteristics and good I-V properties were presented. Also the samples with (NH4)(2)S-x treatment showed the smallest frequency dispersion near the flat-band region and a minimum D-it value of 2.6 x 10(11) cm(-2) eV(-1).