Electrical and photoresponse properties of CoSO4-PVP interlayer based MPS diodes

The cobalt sulfate-polyvinylpyrrolidone (CoSO 4 -PVP) solution was deposited on n-Si crystal by using spin-coated method. The electrical and photoresponse properties of Au/(CoSO 4 -PVP)/n-Si MPS diode were investigated both in the dark and under illumination (100 mW/cm 2 ) level. MPS-type diode exhibits good rectifying behavior in dark condition. The measured reverse current under illumination was found to be higher than dark condition. The MPS diode has also a good response to the illumination and photosensitivity value was found as 5.25 × 10 3 for 100 mW/cm 2 . The diode parameters such as n , Φ b0 and R s were extracted based on both the thermionic-emission (TE) and Norde method. The current conduction mechanisms of the MPS diode were also analyzed by forward ln(I F )-ln(V F ) and reverse ln(I R )-V R 1/2 plots. Moreover, both the voltage dependence of C and G characteristics were investigated under 1 MHz. The other electrical parameters such as V 0 , V D , N D , E F , W D and Φ B were extracted from the C −2 –V characteristics. Besides, the voltage dependence profile of the N ss was extracted by using dark-illumination capacitance (C dark -C ill ) measurements at a frequency of 1 MHz. The results suggest that the prepared Au/(CoSO 4 -PVP)/n-Si MPS diode can be used in optoelectronic device applications.