Zinc Oxide (ZnO) nanostructure thin films have been deposited on various substrates including glass, quartz, Indium Tin Oxide (ITO) coated on glass substrates, and p-Si wafer using chemical spray pyrolysis(CSP) technique at different thickness were employed to assess thin film properties and applications as optoelectronic devise. The structural and optical properties of fabricated ZnO deposited on p-Si substrate were investigated. The electrical properties of (Al/ZnO/p-Si/Al) solar cell were investigated by C-V and I-V (dark and illuminated) measurement. Also we are fabricated (Au/ZnO/p-Si) photoconductive detector at different thickness and have been investigated. The spectral response of detector was calculated.