High-performance CMOS-compatible self-aligned In0.53Ga0.47As MOSFETs with GMSAT over 2200 µS/µm at VDD = 0.5 V

We demonstrate high-performance self-aligned In_0.53Ga_0.47As-channel MOSFETs with effective channel length L_EFF down to 20 nm, peak transconductance G_MSAT over 2200 μS/μm at L_EFF = 30 nm and supply voltage V_DD = 0.5 V, thin inversion oxide thickness T_INV = 1.8 nm, and low series resistance R_EXT = 270 Ω.μm. These MOSFETs operate within 20% of the ballistic limit for L_EFF ≤ 30 nm and are among the best In_0.53Ga_0.47As FETs in literature. We investigate the effects of channel/barrier doping on FET performance and show that increase in mobility beyond ~ 500 cm²/Vs has progressively smaller impact as L_EFF is scaled down. Our self-aligned MOSFETs were fabricated using a CMOS-compatible process flow that includes gate and spacer formation using RIE, source/drain extension (SDE) implantation, and in-situ-doped raised source/drain (RSD) epitaxy. This process flow is manufacturable and easily extendable to non-planar architectures.