skip to main content

Title: Atom probe tomography study of internal interfaces in Cu{sub 2}ZnSnSe{sub 4} thin-films

We report on atom probe tomography studies of the composition at internal interfaces in Cu{sub 2}ZnSnSe{sub 4} thin-films. For Cu{sub 2}ZnSnSe{sub 4} precursors, which are deposited at 320 °C under Zn-rich conditions, grain boundaries are found to be enriched with Cu irrespective of whether Cu-poor or Cu-rich growth conditions are chosen. Cu{sub 2}ZnSnSe{sub 4} grains are found to be Cu-poor and excess Cu atoms are found to be accumulated at grain boundaries. In addition, nanometer-sized ZnSe grains are detected at or near grain boundaries. The compositions at grain boundaries show different trends after annealing at 500 °C. Grain boundaries in the annealed absorber films, which are free of impurities, are Cu-, Sn-, and Se-depleted and Zn-enriched. This is attributed to dissolution of ZnSe at the Cu-enriched grain boundaries during annealing. Furthermore, some of the grain boundaries of the absorbers are enriched with Na and K atoms, stemming from the soda-lime glass substrate. Such grain boundaries show no or only small changes in composition of the matrix elements. Na and K impurities are also partly segregated at some of the Cu{sub 2}ZnSnSe{sub 4}/ZnSe interfaces in the absorber, whereas for the precursors, only Na was detected at such phase boundaries possibly due to amore » higher diffusivity of Na compared to K. Possible effects of the detected compositional fluctuations on cell performance are discussed.« less
Authors:
; ; ;  [1] ; ; ;  [2]
  1. Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Strasse 1, 40237 Düsseldorf (Germany)
  2. Laboratory for Photovoltaics, Physics and Materials Science Research Unit, University of Luxembourg, L-4422 Belvaux (Luxembourg)
Publication Date:
OSTI Identifier:
22494839
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 118; Journal Issue: 9; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; COPPER; COPPER COMPOUNDS; GLASS; GRAIN BOUNDARIES; GRAIN GROWTH; IMPURITIES; INTERFACES; MATRIX ELEMENTS; POTASSIUM; PROBES; SELENIUM; SODIUM; SODIUM CARBONATES; THIN FILMS; TIN; TOMOGRAPHY; ZINC; ZINC SELENIDES