Optoelectronic and photo response performance of n-tris phenylpyridinato iridium/p-Si heterojunction device for photovoltaic applications

Tris 2-phenylpyridinato-C2, N Iridium III [Ir(ppy)3], was evaporated onto a p-type silicon sheet using a thermal evaporation process to create an n-Ir(ppy)3/p-Si junction. Some structural and topographical properties were investigated. Depending upon the forward bias voltage range, thermionic emission and space charge limited current (SCLC) appear to be the conduction mechanisms involved. For this device, we found the ideality factor (N) and reverse saturation current (Is) were evaluated and reported to be 8.07 x 10-9 and 7.8 x 10-9 A, respectively, at room temperature. The value of the diffusion potential (Vdo) was estimated from C-V characteristics both in the dark and at room temperatures. In addition, under illumination, we found the short-circuit current of the device to be Isc = 0.77 mA, the open-circuit voltage to be Voc = 0.42 V, the filling factor to be FF = 0.33%, and the photo-conversion efficiency to be eta = 5.33%.