Device Characteristics of InGaSb/AlSb High-Hole-Mobility FETs

This letter reports the effect of growth temperature on carrier transport characteristics in In
_0.4
Ga
_0.6
Sb/AlSb heterostructure and demonstrates that hole mobility was enhanced by eliminating a parallel conducting channel in the buffer layers. Based on optimized growth conditions, hole mobility as high as 1220 cm
²
/V·s with carrier concentration of 1.3 ×10
¹²
cm
^-2
was achieved. A 0.2- μm-gate-length In
_0.4
Ga
_0.6
Sb/AlSb p-channel device exhibited a maximum drain current of 102 mA/mm, a peak transconductance of 92 mS/mm, and an on-state breakdown voltage over 3 V. The pinchoff was observed for a gate bias of 0.6 V at drain current of 1 mA/mm. The current-gain and power-gain cutoff frequencies were 15 and 20 GHz, respectively.