Determination of energy and spatial distribution of oxide border traps in In0.53Ga0.47As MOS capacitors from capacitance-voltage characteristics measured at various temperatures

In this work, we have systematically studied the frequency dispersion of the capacitance-voltage (C-V) characteristics of In0.53Ga0.47As metal-oxide-semiconductor (MOS) capacitors in accumulation region at various temperatures based on a distributed border traps model. An empirical method to evaluate the frequency and temperature dependent response of the border traps distributed along the depth from the interface into the oxide is established. While the frequency dependent response results from the dependence of the time constant of the border traps on their depths, the temperature dependent response is ascribed to the thermal activated capture cross-section of the border traps due to the phonon-related inelastic capturing process. Consequently, it is revealed that the frequency dispersion behaviors of the accumulation capacitance at different temperatures actually reflect the spatial distribution of the border traps. On this basis, we propose a methodology to extract the border trap distribution in energy and space with emphasis on analyzing the C-V characteristics measured from low to high temperatures in sequence. (C) 2014 Elsevier Ltd. All rights reserved.