AlGaN/GaN high electron mobility transistors based on InGaN/GaN multi-quantum-well structures with photo-chemical vapor deposition of SiO2 dielectrics
AlGaN/GaN metaloxide-semiconductor high electron mobility transistor (MOS-HEMT) based on InGaN/GaN multi-quantum-well (MQW) structure has been fabricated with SiO2 dielectric deposited via photo-chemical vapor deposition (PHCVD) using a deuterium lamp as the excitation source. High quality SiO2 was successfully formed by PHCVD and it exhibited exactly stoichiometric as gate oxide and passivation dielectric for MQW-based MOS-HEMT. The protection offered by the passivation of PHCVD of SiO2 may contribute to the significantly reduced current dispersion and improved RF performance. With 1-?m-long gate length at drainvoltage of 10V, it exhibited a maximum drain current Id(max) of 966mA/mm and a peak transconductance gm(max) of 127mS/mm, while the unity gain cutoff frequency (fT) and maximum frequency of oscillation (fmax) are 13.9 and 33.9GHz, respectively.
gan photo-chemical vapor deposition sio2 mqw hemt