Annealing temperature and stabilizer effects on morphological evolution of Cu2CoSnS4 films on thermally oxidized Si wafers via direct spin-coating

摘要

Earth abundant copper based quaternary chalcogenide Cu2CoSnS4 (CCTS) films were processed by using nontoxic, direct solution-spin-coating process on thermally oxidized Si wafers. Monoethanolamine (MEA) stabilizer effects on chemical composition, crystalline phase, and morphology of the CCTS films were investigated. A systematic study on crystal phase, chemical composition and film morphology evolution including grain size and crack formation, corresponding to annealing condition, were performed via X-ray diffraction, FEG-SEM, and energy dispersive spectroscopy. The cracks free CCTS films were obtained at annealing temperature (T 550 degrees C). The electrical properties of two-terminal CCTS devices processed at different annealing conditions were systematically analyzed by transfer length method (TLM) patterns. The lower resistivity (rho similar to 39.66 Omega cm) and contact resistance (R-c similar to 12.3 +/- 26 k Omega) for CCTS films annealed at 550 degrees C, as compared to low annealing temperature, were extracted and validated with CCTS film thickness and grain sizes supported by XRD and SEM studies. (C) 2018 Elsevier B.V. All rights reserved.