Electrical and optical properties of ZnO/Si photodiodes with embedded CdTe and CdSe/ZnS nanoparticles

Photodiodes based on ZnO/Si heterostructures were fabricated by sputter deposition of polycrystalline n-ZnO films on p-Si substrates. CdTe and CdSe/ZnS nanoparticles were embedded at the junction in between Si substrate and ZnO thin films. The effect of nanoparticles embedding on electrical and optical properties of ZnO/Si photodiodes has been studied. I–V and photocurrent spectra measurements revealed that embedding of nanoparticles significantly lowers the dark current of ZnO/Si photodiodes and also increases light absorption at around 600 nm for ZnO/Si photodiodes.