Characterization of nanocrystalline cadmium telluride thin films grown by successive ionic layer adsorption and reaction (SILAR) method

Abstract

Structural, electrical and optical characteristics of CdTe thin films prepared by a chemical deposition method, successive ionic layer adsorption and reaction (SILAR), are described. For deposition of CdTe thin films, cadmium acetate was used as cationic and sodium tellurite as anionic precursor in aqueous medium. In this process hydrazine hydrate is used as reducing agent and NH 4 OH as the catalytic for the decomposition of hydrazine. By conducting several trials optimization of the adsorption, reaction and rinsing time duration for CdTe thin film deposition was done. In this paper the structural, optical and electrical properties of CdTe film are reported. The XRD pattern shows that films are nanocrystalline in nature. The resistivity is found to be of the order of 4⋅ ⋅11 × × 10 3 Ω Ω-cm at 523 K temperature with an activation energy of ~ 0⋅ ⋅2 eV. The optical absorption studies show that films have direct band gap (1⋅ ⋅41 eV).

Characterization of vacuum evaporated CdTe thin films prepared at ambient temperature

“…Our value of the average grain size is approximately the same as that calculated by Sotelo-Lerma et al [5] for CdTe thin films prepared by the chemical deposition method which is 21 nm. Also it is close to the value calculated by Ubale et al [21] (22 nm) for CdTe thin films prepared by chemical deposition method: successive ionic layer adsorption and reaction (SILAR). But our value of grain size is smaller than the values obtained by Darwish [18], which ranged between 79 and 125 nm for thermal evaporated CdTe thin films.…”

“…Physical techniques include close space sublimation (CSS) [4,8], molecular beam epitaxy (MBE) [9], r.f sputtering [10], electrodeposition [11][12][13], pulsed laser deposition (PLD) [14][15], and thermal evaporation [2,6,[16][17][18]. Chemical techniques include metal organic chemical vapor deposition (MOCVD) [19], chemical bath deposition (CBD) [20], successive ionic layer adsorption and reaction method (SILAR) [21][22], and spray pyrolysis [12,23,24]. Thermal evaporation was choose to produce CdTe thin films in this work because the deposition of CdTe films by this technique does not present any compositional problems [1]; that is approximately no impurities are introduced in the films during the deposition process.…”

Influence of Zn 2+ doping on the crystal structure and optical–electrical properties of CdTe thin films

“…The calculated value of the average crystallite size of pure CdTe (as well as doped CdTe) is smaller than the values obtained by Darwish [39] for thermal evaporated CdTe thin films. Also, it is closer to the values calculated by Ubale et al [40] for CdTe thin films prepared by chemical deposition method: successive ionic layer adsorption and reaction (SILAR). The variation of the unit cell volume and crystallite size with different concentration of Zn 2+ in the host CdTe matrixes has been verified and it is shown in the Supplementary Material (Fig.…”

Effect of annealing on chemically deposited polycrystalline CdTe thin films

“…This is due to depletion of the ions in the bath. Similar results were reported by Ubale et al [12] and Chopra and co-workers [13]. The layer thickness of CdTe thin films was calculated by weight difference density method and was found to be 0.3 m for as-deposited CdTe thin films…”