One-step electrodeposition process of CuInSe2: Deposition time effect

Abstract

CuInSe 2 thin films were prepared by one-step electrodeposition process using a simplified twoelectrodes system. The films were deposited, during 5, 10, 15 and 20 min, from the deionized water solution consisting of CuCl 2, InCl 3 and SeO 2 onto ITO-coated glass substrates. As-deposited films have been annealed under vacuum at 300 °C during 30 min. The structural, optical band gap and electrical resistivity of elaborated films were studied, respectively, using X-ray diffraction (XRD), Raman spectroscopy, UV spectrophotometer and four-point probe method. The micro structural parameters like lattice constants, crystallite size, dislocation density and strain have been evaluated. The XRD investigation proved that the film deposited at 20 min present CuInSe 2 single phase in its chalcopyrite structure and with preferred orientation along (1 1 2) direction, whereas the films deposited at 5, 10 and 15 min show the CuInSe 2 chalcopyrite structure with the In 2 Se 3 as secondary phase. We have found that the formation mechanism of CuInSe 2 depends on the In 2 Se 3 phase. The optical band gap of the films is found to decrease from 1⋅17 to 1⋅04 eV with increase in deposition time. All films show Raman spectra with a dominant A 1 mode at 174 cm-1 , confirming the chalcopyrite crystalline quality of these films. The films exhibited a range of resistivity varying from 2.3 × 10-3 to 4.4 × 10-1 Ω cm.

Properties of Electrosynthesized Cobalt Doped Zinc Selenide Thin Films Deposited at Varying Time

“…This confirmed the prospect offered in energy bandgap engineering of cobalt doped zinc selenide by altering deposition time. Similar effects on bandgap due to changes in deposition time using electrodeposition techniques have been reported by [44,[47][48][49][50].…”

“…With this range of absorbance values, the deposited thin films of cobalt doped zinc selenide could be found applicable in the buffer layer of a thin-film solar cell and other optoelectronics device fabrications. Similar effects on the absorbance of thin film as deposition time increases have been obtained by [44,47]. Figure 5 shows the graph of transmittance spectra plotted against wavelength for cobalt doped zinc selenide thin films synthesized under different deposition times.…”