Characterization of the surface recombination velocity of HgCdTe using a gate-controlled diode

Abstract

A four-terminal gate-controlled diode structure has been used to characterize the surface recombination velocity of HgCdTe. The electrical performance of the gate-controlled diode fabricated using x = 0.3 HgCdTe was characterized by capacitance-gate voltage and current-gate voltage measurements. A theoretical model was developed for the total dark current in the gate-controlled diode structure and used to fit the experimental data. Data fitting when the experimental device was operated in depletion mode allowed the simultaneous extraction of the surface recombination velocity, 170 cm/s, the generation lifetime in the n-p junction depletion region, 12 ns, and the generation lifetime in the gate induced junction depletion region, 500 ns.