TEM and XPS studies on CdS/CIGS interfaces

• Published in: The Journal of physics and chemistry of solids Vol. 75; no. 12; pp. 1279 - 1283
• Main Authors: Han, Jun-feng, Liao, Cheng, Cha, Li-mei, Jiang, Tao, Xie, Hua-mu, Zhao, Kui, Besland, M.-P.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2014
• Subjects: A. Chalcogenides; A. Interfaces; A. Thin films; C. Electron microscopy; C. Photoelectron spectroscopy; C. Electron microscopy; A. Thin films; A. Interfaces; C. Photoelectron spectroscopy; A. Chalcogenides
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/j.jpcs.2014.06.002

Copper indium gallium selenide (CIGS) was deposited by metallic precursors sputtering and subsequently submitted to a selenization process. The upper CdS layers were deposited by chemical bath deposition (CBD) technique. The CdS/CIGS interfaces were investigated by Transmission Electron Microscopy (TEM) and X-ray Photoelectron Spectroscopy (XPS). As checked by XPS analysis, the CIGS surface exhibited a hydroxide-terminated CdSe layer when treated with Cd Partial Electrolyte solution (Cd PE). Its thickness was roughly estimated to several nanometers. A 100nm thick CdS layer was deposited onto CIGS surface. The TEM images revealed a clear and sharp interface between CdS and CIGS. XPS analysis showed a CIGS surface covered by a pinhole free and homogeneous CdS layer. XPS depth profile measurement of the CdS/CIGS interface did not evidence elemental inter-diffusion between the CIGS and CdS layers, in very good agreement with TEM observations. [Display omitted] •An indium rich and Ga, Cu poor surface of CIGS thin film was observed.•A hydroxide-terminated CdSe layer in the CIGS surface after Cd PE treatment.•TEM observation of CdS/CIGS interface.•XPS depth profile of CdS/CIGS interface.