Fabrication of three-component metal oxide based photosensors

The investigation electric and optic characteristics of the fabricated Al/(CdO:ZnO:NiO:Ti)/p-Si (5:2:2:1) photodiode in dark and under 100 mW/cm2 in the voltage range of ±4V. Their basic electrical parameters such as ideality-factor (n), reverse saturation current (I0), the formation of barrier-height (Bo) at metal/semiconductor interface, series/shunt resistances (Rs, Rsh), rectification-ratio (RR=IF/IR ±4V) were calculated by using thermionic-emission (TE) theory. Both the energy dependent of (Nss-(Ess-Ev)) and voltage dependent resistance (Ri) distributions were obtained from the Card-Rhoderick and Ohm Law, respectively. Among these parameters n, Rs, and Bo was also calculated from the Norde and Cheung functions and compared with both TE and available literature. Optical parameters that determine the light-dependent sensitivity of a photodiode like photo-sensitivity (S), photo-responsibility (R), and photo-detectivity (D*) values were also obtained. Obtained results show that the fabricated photodiode has good rectification ratio and more sensitivity to illumination so can be successfully used in solar cells and optical applications instead in conventional metal/insulator/semiconductor (MIS) photodiodes. The ln(IF)-ln(VF) plots have also show three different linear regimes with different slopes. Among Ohmic, space charge limited current (SCLC), and trap charge limited current (TCLC) mechanisms, in current conduction mechanism, which was dominated determined by using the slopes of these linear parts.