Characterization of CdTe nanoparticles fabricated by pulsed electron deposition technique at different ablation parameters

Cadmium Telluride (CdTe) is a front-runner photovoltaic (PV) material because it has already attained efficiencies above 16%. The fabrication of CdTe nanoparticles has aroused considerable interest because of their potential application as active layer in organic/inorganic hybrid solar cells. They can also be used for sensitisation of wide band gap semiconductors. In this work, we explore pulsed electron beam deposition (PED) technique to fabricate CdTe nanoparticles. Two ablation parameters, namely background gas pressure and electron energy, were varied to investigate their effects on the nanoparticle formation. Optical transmission measurements and SEM indicate that we have deposited CdTe nanocrystalline films exhibiting quantum confinement effects. From AFM, these films are as smooth as the Si substrate. In addition to the smooth film, larger nanoparticles with diameters varying from 40 nm to 500 nm were also deposited on the substrate. They contribute to the absorption onset at the bulk band gap energy.