The characterization of InAlN/AlN/GaN HEMTs using silicon-on-insulator (SOI) substrate technology

The microwave and low frequency noise characteristics of 6 inch InAlN/AlN/GaN high electron mobility transistor (HEMT) were demonstrated and investigated on silicon-on-insulator (SOI) substrate for the first time. The InAlN HEMT on SOI substrate was grown by metal organic chemical vapor deposition (MOCVD) on a p-type (111) Si SOI substrate with a p-type (100) Si handle wafer for possible heterogeneous integration. The Raman spectroscopy measurement indicates that the smaller epitaxy stress was obtained by adopting SOI wafer and X-ray diffraction measurements revealed that InAIN HEMT on SOI achieves a flat surface and an abrupt heterointerface. The InAlN HEMT on SOI exhibits a lower leakage current compared to the device on high resistivity (HR) Si substrate and thus improves the off-state breakdown voltage from 134 V to 198 V. Moreover, the buried SiO₂ in SOI substrate also efficiently suppresses the signal loss resulting in the better bandwidth and the microwave power performance. Based on the low frequency noise measurement, InAlN HEMT on SOI substrate also performs a relatively slight degradation after hot carrier stress.