Electrodeposition of chalcopyrite films from ionic liquid electrolytes

• Published in: Thin solid films 2007-05, Vol.515 (15), p.5899-5903
• Main Authors: Shivagan, D.D., Dale, P.J., Samantilleke, A.P., Peter, L.M.
• Format: Article
• Language: English
• Subjects: Chalcopyrite; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Cu(In, Ga)Se 2; Electrodeposition; Electrodeposition, electroplating; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport phenomena in thin films and low-dimensional structures; Exact sciences and technology; Ionic liquid electrolytes; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Photoconduction and photovoltaic effects; photodielectric effects; Photoelectrochemical measurements; Physics; Surface and interface electron states
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2006.12.092

An air and water stable room-temperature ionic liquid based on choline chloride/urea eutectic mixture has been investigated as a system for the electrodeposition of CuInSe 2 (CIS) and Cu(In,Ga)Se 2 (CIGS) films for photovoltaic applications. Deposition potentials and bath compositions were optimized to obtain Cu–In, Cu–In–Se and Cu–In–Ga–Se precursor films, which were selenized in a tube furnace at 500 °C for 30 min to form CIS and CI(G)S films. Photo-electrochemical measurements on these selenized films showed p-type photoconductivity with band gaps of 1.0 eV and 1.09 eV, respectively, for CIS and CIGS. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photocurrent spectroscopy and electrolyte electro-reflectance spectroscopy (EER).