Preparation And Preformance Study Of The CdS/Si Nano Heterojunction Arrays

CdS/Si nanowire heterostructure arrays were prepared by SILAR technique based on etched Si nanowire templates using p-type(100) silicon wafer. Synthesized Cd S/Si nanowire heterostructures were characterized by Zeiss Super40 field emission scanning electron microscopy respectively, the crystalline structures of samples were characterized by using X-ray diffractometer(DX-2000),and the wavelength of incident light dependence of transmittance.In addition, photoluminescence(PL) spectrum of Cd S/Si nano-heterojunction measurement and analysis system under the room temperature. By making two-sided electrode structure,fabricated Ag / Cd S / Si nano-heterojunction / sc-Si / Al heterojunction solar cells prototype device, further testing and analysis of its photovoltaic properties.At room temperature,as well as without light conditions, Cd S / Si nano-heterostructures showed a significant effect of rectification, turn-on voltage is ~ 1.6ev, corresponding to a current density of ~ 1.25 m A/cm2 and the everse voltage show ~7.5ev.Under different cycles,the turn-on voltage of will be different, and increasing the number of cycles the threshold voltage will be increased.The greater of open circuit voltage show the separation of photo-generated carriers could be well happen, and if the short-circuit current is relatively large means the photo-generated carriers can be more effective transmission and gathering.The no-annealed Cd S/Si nano-heterojunction photovoltaic performance parameters are Jsc = 0.793 m A / cm2, FF = 0.215, Vsc = 0.212 V and η = 0.145%.The samples that annealed at different temperatures, the open circuit voltage were 0.212 e V, 0.034 e V, 0.029 e V, 0.101 e V, and 0.178 e V, open circuit voltage increases as the temperature gradually increased, the open circuit voltage is relatively high under the annealing temperature of 500℃, indicating that the leakage current is relatively small, attributed to the band gap changed.In addition, short-circuit current of the samples were 0.793 m A / cm2, 0.0023 m A / cm2, 0.0035 m A / cm2, 0.00328 m A / cm2 and 0.08331 m A / cm2. Because of the annealing temperature increases,caused the series resistance decreased. The series resistance of the samples were 0.293 k ?, 12.483k?, 7.096k?, 29.021k?, 1.823k?and the energy conversion efficiency respectively was 0.145%, 0.9 × 10-4%, 0.1 × 10-4%, 0.33 × 10-4%, 0.016%.