Characterization and photovoltaic performance analysis of Na2Pc/p-Si heterojunction solar cell

A hybrid (organic/inorganic) heterojunction solar cell was fabricated by vacuum deposition of disodium phthalocyanine (Na2Pc) film onto a p-type silicon substrate. The structural and morphological characteristics of the Na2Pc thin films were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The absorption coefficient, alpha, of Na2Pc thin films was examined to be greater than 10(5) cm(-1), while the energy gap value was found to be 2.25 eV. The dark current-voltage characteristics of the device at various temperatures were measured. The device parameters such as series resistance, R-s, shunt resistance, R-sh, effective barrier height, phi(b), ideality factor, n, rectification ratio, RR, and traps concentration, N-t, were estimated. The results showed that the device has non-ideal behavior. The dominant conduction mechanisms of the forward bias were determined as thermionic emission and space charge limited current (SCLC) at low and high voltage, respectively. According to the analysis of I-V curves in reverse bias, Poole-Frenkel and Schottky conduction processes showed dominance at low and high voltages, respectively. Also, the modified Norde's function was used to determine R-s and phi(b) at different temperatures. The energy band diagram of the Na2Pc/p-Si heterojunction is created. Under constant illumination of 200 W/m(2), the device exhibited photovoltaic behavior with a power conversion efficiency, eta, of 3.11%.

Automated summary

In this study, a hybrid heterojunction solar cell was fabricated and the characteristics and behavior of the device were investigated by studying the structure and properties of Na2Pc thin films.