Research Article of International Journal of Nanoparticle Research
Processing and Characterization of Vacuum-Free CuInSe2 Thin Films from Nanoparticle-Precursors using Novel Temperature Treatment Techniques
Matthias Schuster*, Philipp Sisterhenn, Lorenz Graf, Peter J. Wellmann
Materials Department 6 (i-MEET), Martensstr. 7, 91058 Erlangen, Germany, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)
The objective of this work is the processing and characterization of a dense CuInSe2 solar-cell-absorber-layer based on nanoparticulate precursors. Bimetallic copper-indium- and elemental selenium-nanoparticles were synthesized by wet-chemical processes and then dispersed in organic solvents as nano-inks. These inks were then printed into different layer-stacks on a molybdenum coated float-glass-substrate via doctor-blading. The temperature treatment to transform these layer-stacks into dense CISe thin films was investigated, using a face-to-face technique and mechanically applied pressure or the repetition of coating and annealing. All absorber layers were characterized with SEM, EDX and XRD. Dense, coarse grained CuInSe2 layers with a thickness ≈ 7 µm were formed and the application of mechanical pressure shows potential to reduce thickness and sinter together the nanoparticles to large grains of ca. 3 µm in size. The face-to-face-annealing ensured keeping a stoichiometric ratio of (Cu+In) / Se ≈ 1, and can help reducing the content of oxides, even when the annealing is performed in ambient atmosphere. With a repetition of coating and annealing, dense CISe layers could be produced at low temperature of only 350 °C.
Keywords: CuInSe2, solar cell absorber, nanoparticles, vacuum-free, face-to-face annealing, uniaxial pressure
How to cite this article:
Matthias Schuster*, Philipp Sisterhenn, Lorenz Graf, Peter J. Wellmann. Processing and Characterization of Vacuum-Free CuInSe2 Thin Films From Nanoparticle-Precursors Using Novel Temperature Treatment Techniques. International Journal of Nanoparticle Research, 2018; 2:4. DOI:10.28933/ijnr-2017-12-1501
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