Impact of sidewall passivation and channel composition on In_xGa_1-xAs FinFET performance

We experimentally demonstrate In_xGa_1-xAs FinFET devices with varying indium composition and quantum confinement effect. While increasing indium content enhances drive current by increasing the injection velocity, increasing quantum confinement enhances the drive currents by significantly improving the short-channel effects. Further, improved sidewall passivation using an in situ plasma nitride passivation process provides additional improved subthreshold behavior. Competitive drive currents are obtained with FinFETs realized through a scaled fin pitch process allowing 10-fins/μm layout width at a fin width of 20 nm. We report field effect mobility from multifin split-capacitance-voltage (split-CV) measurements having peak mobility of 3480 cm²/V·s for a 10-nm QW FinFET with 70% indium. Peak transconductance (g_mmax) of 1.62 mS/μm, normalized to circumference, is demonstrated for devices with L_G=120 nm.