Influence of interface states and deep levels on output characteristics of InAlAs/InGaAs/InP HEMTs

The aim of this work is to study the origin of parasitic effects observed on the output characteristics of InAlAs/InGaAs/InP HEMTs with various buffer layers. Ids − Vds measurements as a function of the temperature have first been performed. Several anomalies were observed such as kink and hysteresis effects. C-DLTS measurements have also been performed. From the obtained results, we have established a strong correlation between parasitic effects observed on the output characteristics and deep levels located near the buffer layer interface.