Sb-Based n- and p-Channel Heterostructure FETs for High-Speed, Low-Power Applications

Heterostructure field-effect transistors (HFETs) composed of antimonide-based compound semiconductor (ABCS) materials have intrinsic performance advantages due to the attractive electron and hole transport properties, narrow bandgaps, low ohmic contact resistances, and unique band-lineup design flexibility within this material system. These advantages can be particularly exploited in applications where high-speed operation and low-power consumption are essential. In this paper, we report on recent advances in the design, material growth, device characteristics, oxidation stability, and MMIC performance of Sb-based HEMTs with an InAlSb upper barrier layer. The high electron mobility transistors (HEMTs) exhibit a transconductance of 1.3 S/mm at VDS = 0.2 V and an fT Lg product of 33 GHz-μm for a 0.2 μm gate length. The design, fabrication and improved performance of InAlSb/InGaSb p-channel HFETs are also presented. The HFETs exhibit a mobility of 1500 cm2/V-sec, an fmax of 34 GHz for a 0.2 μm gate length, a threshold voltage of 90 mV, and a subthreshold slope of 106 mV/dec at VDS = −1.0 V. key words: HEMTs, HFETs, MMICs, InAs, InGaSb