Fully subthreshold current-based characterization of interface traps and surface potential in III–V-on-insulator MOSFETs

• We propose a fully subthreshold current-based technique for both Dit(E) and ψS,eff in the nonlinear mapping of VGS to Et in InGaAs-OI MOSFETs.
• Both the energy state mapping and Dit(E) were achieved from the differential body coupling factor.
• Simultaneous nonlinear mapping of VGS to Dit(E) through ψS,eff though the subthreshold current model.

We report characterization of the interface trap distribution (Dit(E)) over the bandgap in III–V metal–oxide–semiconductor field-effect transistors (MOSFETs) on insulator. Based only on the experimental subthreshold current data and differential coupling factor, we simultaneously obtained Dit(E) and a nonlinear mapping of the gate bias (VGS) to the trap level (Et) via the effective surface potential (ψS,eff). The proposed technique allows direct extraction of the interface traps at the In0.53Ga0.47As-on insulator (-OI) MOSFETs only from the experimental subthreshold current data. Applying the technique to the In0.53Ga0.47As channel III–V-OI MOSFETs with the gate width/length W/L = 100/50, 100/25, and 100/10 μm/μm, we obtained Dit(E) ≅ 1011–1012 eV−1 cm−2 over the bandgap without the dimension dependence.