Electrical properties of Er-doped CdS thin films

Abstract

Cadmium sulfide thin films were prepared by chemical bath on glass substrates at 80°C. CdS was Er-doped during the growth process by adding water-diluted Er(NO3)33∙H2O to the CdS aqueous growing solution. The relative volume of the doping solution was varied in order to obtain different doping levels. The crystalline structure of CdS:Er films was cubic zinc blende for all the doped layers prepared. The (111) interplanar distance has an irregular variation with the Er doping level. Consequently, the band gap energy (Eg) firstly increases and afterward diminishes becoming, at last, approximately constant at around Eg=2.37eV. For higher doping levels, in the as-grown films, dark electrical conductivity (σ) values reach 1.8×10−2Ω−1cm−1 at room temperature. The logarithm of σ vs 1∕kT plot, where k is Boltzmann’s constant and T the absolute temperature, indicates an effective doping of CdS as a result of the Er introduction into the lattice of the material. Hall effect measurements reveal a n-type doping with 2.8×1019cm−3 as maximum carrier density.

Crystallization of II-VI semiconductor compounds forming long microcrystalline linear assemblies

“…High purity salts reagents (concentrations) used in the preparation, in this last case, were: CdCl 2 (0.02 M), KOH (0.15 M), NH 4 NO 3 (1.5 M), and SC(NH 2 ) 2 (0.2 M). More details of the growth processes have been previously reported elsewhere [15][16][17][18] . X-ray diffraction (XRD) patterns of samples were registered using the CuKα line of a D5000 Siemens diffractometer.…”

“…In this work we report the formation of mycro and nanocrystal linear chains of CdS and CdTe obtained on glass substrates by conventional CSS, CBD and rf sputtering techniques. We discuss the formation of the linear chains as an early or intermediate stage during the film deposition on glass substrates of the polycrystalline thin films [15][16][17][18] . Among the interaction forces which can cause particles aggregation are electrical and magnetic dipolar (or multipolar) attraction 19,20 , Van der Waals 20 , depletion attraction 21 , optical force 22 , etc.…”

Photoluminescence properties of the ZnO–CdO–TeO2 system doped with the Tb3+and Yb3+ ions

“…Various types of matrices have been used as hosts of the rare earth elements (RE), some of them are bulk glasses [3], TiO 2 [4], and II-IV semiconductors [5,6]. Nevertheless, luminescence of RE is not always observed.…”

Effect of Concentration of Cadmium Acetate and Thiourea on CDS Thin Films and their Characterization

“…For example, rough surfaces of Ga-doped ZnO thin films and smooth surfaces of Al-doped ZnO thin films were obtained using the spray pyrolysis technique. Though there are many reports on doping including Ni [12], Mn [13], Co [14], Al [16], Cr [15], In [17], Sn [18], B [19], Mg [20], Er [21], etc. into CdS, the number of works on Ba, Co and Fe-doped and co-doped CdS thin film is scarce.…”