Effect of hydrodynamic conditions on the Cu(In,Ga)Se2 thin film growth by electrodeposition

• Published in: Materials chemistry and physics Vol. 226; pp. 82 - 87
• Main Authors: Lara-Lara, B., Fernández, A.M., Oviedo-Tolentino, F.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.03.2019; Elsevier BV
• Subjects: Boundary layers; CIGS thin film; Composition; Copper; Copper indium gallium selenides; Electrodeposition; Electrodes; Electrolytic cells; Film growth; Free convection; Morphology; Natural convection flow; Photovoltaic cells; Selenium; Thin films; Natural convection flow; Electrodeposition; CIGS thin film
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2019.01.024

In this paper, an experimental study about CIGS thin film growth due to hydrodynamic conditions variations on the working electrode surface is reported. Local hydrodynamic conditions were produced by the interaction of the natural convection flow with a non-conducting hemisphere placed on the working electrode surface. The electrodeposition process was made by a single bath with copper, indium, gallium and selenium ions to obtain CIGS thin films. The electrodes in the electrolytic cell were placed vertically. The as-electrodeposited CIGS thin film morphology near the hemisphere had a characteristic growth as a consequence of the local hydrodynamic conditions. CIGS thin film morphology and composition variations due to the wake and boundary layer were identified. With the CIGS film morphology obtained due to the presence of the wake was possible to represent the natural convection flow pattern on the Mo electrode surface. The CIGS thin film composition, inside and outside of the wake and throughout the boundary layer, was characterized. The gallium incorporation to the CIGS film was principally affected. As a consequence of this study, it was found that the atomic percentage of gallium in the CIGS film is related to deposition current density. •During the electrodeposition process there is a natural flow by convection.•The atomic composition of a CIGS film is related to the natural convection flow.•The incorporation of gallium to the CIGS film is related to the deposition current.