Effect of illumination intensity on the characteristics of Cu(acac)2/n-Si photodiode

Abstract

Thermally evaporated copper (II) acetylacetonate Cu(acac)2 thin film deposited on the n-Si wafer was used for light detection. The microstructural properties of copper (II) acetylacetonate thin film were investigated using high-resolution transmission electron microscope technique. A polycrystalline nature of Cu(acac)2 film with a clearly resolved lattice fringes were obtained. The optical properties of the thin film deposited on an n-type silicon substrate were investigated using spectroscopic ellipsometry technique which suggested UV and visible light absorption of copper (II) acetylacetonate. The I-V characteristics of the fabricated photodiode were investigated in dark and under different light illumination intensities. The main diode parameters were determined using the Thermionic emission theory and modified Norde's method. The present architecture showed a good response to halogen lamb light, where the estimated values of rise and fall time at 80 mW/cm2 were about 339 ms and 1046 ms, respectively. Furthermore, C-V measurements for the fabricated device were performed in dark at different frequencies.