A Distributive-Transconductance Model for Border Traps in III–V/High-k MOS Capacitors

By in-depth analysis of the electrical response of border traps in gate oxide, a new border-trap model is proposed where the ac charging and discharging current associated with those traps is proportional to the variation of the surface potential of semiconductors, resembling the behavior of transconductors. In contrast, the border trap current is directly related to the local potential in the gate oxide in the existing model. The model is then used to provide a qualitative understanding of the temperature-dependent frequency dispersion observed on the Al₂O₃/n-GaAs(111)A MOS capacitors at high positive bias.