ZN3P2 PHOTOVOLTAIC FILM GROWTH FOR ZN3P2/ZNSE SOLAR-CELL

Zinc phosphide (Zn3P2) thin films have been grown by photo-metalorganic chemical vapor deposition (photo-MOCVD) and also MOCVD onto n-type ZnSe single crystal aiming at p-Zn3P2/n-ZnSe solar cells. A good diode characteristic was observed in p-Zn3P2/n-ZnSe heterojunctions fabricated with annealing in hydrogen at 400 degrees C. An open-circuit voltage (V-OC) of 0.4-0.5 V, a fill factor of 0.6, and a short-circuit current of 2-9 mu A/cm(2) were obtained under simulated air mass 1.5 illumination without anti-reflective coating. One of the reason with this small short-circuit current is the high resistivity and ohmic contact problem of ZnSe. A spectral response of V-OC indicates a good band-pass behavior of the heterojunction between 1.5 and 2.7 eV, which are bandgaps of Zn3P2 and ZnSe, respectively.