A p-Si/CoPc Hybrid Photodiode System for Looking at Frequency and Temperature Dependence on Dielectric Relaxation and AC Electrical Conductivity

In this work, a heterojunction of Al/p-Si/CoPc/Au was fabricated using the thermal evaporation technique by depositing CoPc on the p-Si. Complex impedance spectroscopy was employed to investigate the impedance characteristics and the full band profile measurements of the fabricated heterojunction. Arrhenius fitting of double relaxation operations was utilized to determine the activation energy of the tested device. The studied device gains a negative temperature resistance coefficient as interpreted from the electrical conductivity and Cole–Cole fitting. The lifetimes of the excess minority carriers, the coefficients of carrier diffusion, and the charge carrier mobilities at the interfaces were measured and estimated.