Effect of Cu incorporation on structural and optical properties of nanocrystalline CdSe (nc-CdSe:Cu) thin films

• Published in: Journal of alloys and compounds Vol. 540; pp. 198 - 203
• Main Authors: Sharma, Kriti, Al-Kabbi, Alaa S., Saini, G.S.S., Tripathi, S.K.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 05.11.2012; Elsevier
• Subjects: Alloys; Atomic properties; Cadmium selenides; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Copper; CRYSTAL STRUCTURE; Exact sciences and technology; Luminescence; Nanocrystals and nanoparticles; Nanostructured materials; OPTICAL PROPERTIES; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; PARTICLE SIZE AND SHAPE; Physics; PROPERTIES; REFRACTIVE INDEX; Refractivity; SELENIDES; TEM; THIN FILMS; Vapor deposition; X RAYS; Vapor deposition; Nanostructured materials; TEM; Optical properties; Luminescence; Grain size; Particle size; Refractive index; Doping; Photoluminescence; Copper additions; XRD; Dispersive spectrometry; Absorption coefficients; Cadmium selenides; Thin films; Hexagonal lattices; Energy gap; Transmission electron microscopy; Spherical particle; Vacuum evaporation; Nanocrystal
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2012.06.090

► nc-CdSe:Cu 1% and nc-CdSe:Cu 5% thin films are prepared by thermal evaporation technique. ► The composition of the thin films is determined by EDX. ► Optical band gap (Eg) decreases with increase in the Cu concentration. ► PL intensity enhances as the Cu concentration is increased to 5%. nc-CdSe:Cu 1% and nc-CdSe:Cu 5% thin films have been deposited on glass substrates by thermal vacuum evaporation using the Inert Gas Condensation (IGC) method. Transmission Electron Microscopy (TEM) analysis reveals that the particles are spherical in shape and average particle size increases as the Cu concentration increases. The atomic weight percentage of Cu is determined by the Energy Dispersive X-ray analysis (EDX). X-ray Diffraction (XRD) measurements indicate that the films exhibit hexagonal structure. The grain size calculated from XRD increases as the Cu concentration is increased to 5%. The optical band gap Egopt has been determined from the absorption coefficient values using the Tauc’s procedure. A decrease in the band gap is observed with increase of the Cu concentration. The refractive index (n) is determined from transmittance using the Swanepoel’s method. The refractive index is found to depend on Cu concentration. The Photoluminescence (PL) spectral variation at different concentrations of Cu is studied.