Influence of Zn doping on structural, optical and electrical properties of nanocrystalline CdSe thin films

• Zn 1% and Zn 5% doped CdSe thin films are prepared by thermal evaporation.
• Structural characterization has been done by XRD, SEM and EDX.
• The variation of optical band gap is studied.
• PL intensity increases as the Zn dopant concentration increases from 1% to 5%.
• Variation of electrical conductivity with Zn doping concentration has been studied.

Nanocrystalline Zn doped CdSe thin films with different Zn contents are prepared by thermal evaporation using the Inert Gas Condensation technique. The prepared samples are characterized by Energy dispersive X-ray spectroscopy (EDX), Scanning electron microscope (SEM), X-ray diffractometer (XRD), UV–Vis-IR spectrophotometer and Photoluminescence (PL) techniques, respectively. SEM investigation reveals uniform distribution of the films over the entire substrate surface. XRD results indicate that Zn doped CdSe thin films grew with the hexagonal phase. The variation of the optical band gap with change in Zn dopant concentration has been studied. PL intensity increases for Zn 5% doped nanocrystalline CdSe thin films as compared to doping with Zn 1%. Electrical investigations have also been made for nanocrystalline Zn 1% and Zn 5% doped CdSe thin films. Hall measurements indicate that Zn 1% and Zn 5% doped CdSe thin films are of n type.