Experimental Investigation of Border Trap Generation in InGaAs nMOSFETs With Al2O3 Gate Dielectric Under PBTI Stress

The reliability performance of InxGa1−xAs n-type metal–oxide–semiconductor field-effect transistors with Al2O3 gate dielectric under positive-bias temperature instability stress is investigated systematically. A model of stress-induced border traps was proposed to interpret all charge pumping and I–V experimental results excellently. The stress-induced border traps include recoverable donor traps and permanent acceptor traps with respective energy densities ΔD SOX (E) and ΔD Acceptor SOX (E). The shapes of ΔD SOX (E) and ΔD Acceptor SOX (E) have been extracted from experimental data. ΔD SOX (E) mainly distributes in the conduction band of InGaAs with a tail extending to the mid-gap, whereas ΔD SOX (E) has a large distribution inside the energy gap and extends to the conduction band. The high density of ΔD SOX (E) in the energy gap induces large degradation in the OFF-current, which is particularly serious when the In composition x is raised to 0.65.