Offset wide-recessed In0.49GaP/Al0.45GaAs barrier E-pHEMT with high current density
ABSTRACT An offset wide-recessed In0.49GaP/Al0.45GaAs barrier enhancement-mode p-HEMT (E-pHEMT) with high drain current density has been developed. Achieving high gate-turn-on voltage and reducing source access resistance (RS) were the aims for the high current density E-pHEMT. The wide bandgap Al0.45GaAs barrier enabled the application of high VGS to the gate. RS was reduced by using an In0.49GaP etch stop layer with low surface defect density and reducing the source to gate spacing (LSG). An offset wide-recess to the E-pHEMT was applied to enhance breakdown voltage without increasing RS. The offset wide-recessed 0.5 μm gate E-pHEMT showed a drain current density of 440 mA/mm at VGS=1.5 V and an off-state breakdown voltage of over 21 V.