Influence of the Epitaxy on the Sub-Threshold Drain Leakage Current and the Breakdown Voltage for GaAs pHEMTs

摘要

In this work we present the influence of the buffer on the drain leakage current and breakdown voltage of Al_(0.25)Ga_(0.75)As/In_(0.20)Ga_(0.80)As/Al_(0.25)Ga_(0.75)As double recessed pHEMTs. Three different types of buffers were investigated: a 50 nm thick In_(0.52)Ga_(0.48)P layer, a binary AlAs/GaAs super lattice, and a ternaryAl_(0.60)Ga_(0.40)As/GaAs super lattice. For the latter the thickness of the first Al_(0.60)Ga_(0.40)As layer was also varied. The measurements of the drain leakage current and breakdown voltage are presented and discussed.