Effect of illumination and frequency on the capacitance spectroscopy and the relaxation process of p-ZnTe/n-CdMnTe/GaAs magnetic diode for photocapacitance applications

Heterostructure of p-ZnTe/n-CdMnTe/GaAs (II-VI/II-VI-DMS/III-V) is grown by molecular beam epitaxially growth (MBE). The capacitance-frequency (C-f) characteristics of the prepared heterostructure under dark and different illumination intensities were analyzed. The studied sample shows a capacitance illumination dependence. Modified Goswami and Goswami (G-C) model was used to interpret the capacitance profile under the effect of the irradiated light. The illumination dependence of the relative capacitance (C-ph/C-d) at different frequency was studied and interpreted. The interface density states (N-ss), the interface capacitance (C-ss) and dielectric relaxation time (tau) are increased with the increase of the illumination intensities. Therefore, the prepared heterostructure can be used as photocapacitance sensor in modern electronic and optoelectronic devices. (C) 2010 Elsevier B.V. All rights reserved.