title: Improved Photovoltaic Characteristics and Grain Boundary Potentials of CuIn0.7Ga0.3Se2 Thin Films Spin-Coated by Na-Dissolved Nontoxic Precursor Solution.
abstract: This work introduces the incorporation of Na into the nontoxic precursor solution of CIGS to improve photovoltaic cell performance with the optimized benefits of Na. The extensive incorporation range of 0.05 to 0.5 mol % Na is used for the simple spin-coating process of high quality absorber thin films. A cell efficiency of ∼8.21%, which corresponds to an improvement of ∼10.2% compared to the reference sample, is achieved for the 0.25 mol % Na sample with enhanced open-circuit voltage and fill factor. The improvement was further analyzed as related to InCu defects and grain boundary potentials.
authors.affiliation: Department of Materials Science and Engineering, Yonsei University , Seoul 120-749, Korea.
authors.forename: Ik Jin
authors.initials: IJ
authors.lastname: Choi
authors.affiliation: Department of Materials Science and Engineering, Yonsei University , Seoul 120-749, Korea.
authors.forename: Jin Woo
authors.initials: JW
authors.lastname: Jang
authors.affiliation: School of Physics & Materials Science, Thapar University , Patiala 147004, India.
authors.forename: Bhaskar Chandra
authors.initials: BC
authors.lastname: Mohanty
authors.affiliation: Department of Materials Science and Engineering, Yonsei University , Seoul 120-749, Korea.
authors.forename: Seung Min
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Yonsei University , Seoul 120-749, Korea.
authors.forename: Yong Soo
authors.initials: YS
authors.lastname: Cho
keywords: Na-incorporation; chalcopyrite; grain boundary; solution deposition; thin film solar cells