Investigation of electrical characteristics on 25-nm InGaAs channel FinFET Using InAlAs back barrier and Al₂O₃ gate dielectric

We investigated an N-type III–V FinFET with a 25-nm In_0.53Ga_0.47As channel and a 300-nm In_0.52Al_0.48As barrier layer on an InP substrate. The In_0.52Al_0.48As barrier layer is used to suppress leakage current from the InP substrate and the 10-nm Al₂O₃ film deposited by atomic layer deposition (ALD) can be a robust gate dielectric to mitigate interface traps. The on to off current ratio is approximately three orders of magnitude, the subthreshold swing (SS) is 350 mV/dec, and the maximum driving current density is 130 μA/μm at V_G = 1.5 V for InGaAs FinFET with a fin width of 40 nm and gate length of 200 nm.