InP/InGaAs Composite Metal–Oxide–Semiconductor Field-Effect Transistors with Regrown Source and Al₂O₃Gate Dielectric Exhibiting Maximum Drain Current Exceeding 1.3 mA/µm

Abstract

We have realized InP/InGaAs composite-channel metal–oxide–semiconductor field-effect transistors with both selectively regrown n+-InGaAs source/drain regions and Al2O3 as a gate dielectric. A 100-nm-long channel was fabricated by laterally buried regrowth in a channel undercut by metalorganic vapor phase epitaxy. The carrier density of the regrown layer was 2.9×1019 cm-3. A drain current Id of 1.34 mA/µm was achieved at a drain voltage Vd of 1 V and a gate voltage Vg of 3 V. A transconductance gm of 817 µS/µm at Vd = 0.65 V was also observed at the same time. The improvement in the subthreshold slope can be explained by the decrease in dielectric/semiconductor interface trap density.