Fig. 1 | Nature Communications

Fig. 1

From: Composition change-driven texturing and doping in solution-processed SnSe thermoelectric thin films

Fig. 1

Solution-processed fabrication of highly textured SnSe thin films. a Schematic illustration of the fabrication process of SnSe thin films. SnSe ink solution was synthesized by a two-step process, which involves dissolving SnSe powder in a solvent composed of ethylenediamine and ethanedithiol, and purifying the resulting solution with acetonitrile to obtain a precipitate. The precipitate was dissolved in ethylenediamine to obtain the SnSe ink solution. The ink was spin-coated on a glass substrate and the film was heated for 1 min at 400 °C. The coating process was repeated to obtain the desired thickness. Finally, the film was annealed at 400 °C for an appropriate time. The photograph shows the fabricated film had a mirror-like reflection, indicating high uniformity. b SEM image of the SnSe thin film fabricated with purified precursor solution shows full coverage of SnSe on the substrate. Scale bar, 5 μm. Cross-sectional SEM image (inset) shows a uniform thickness of 85 nm. Scale bar, 500 nm. c XRD pattern of the SnSe thin film fabricated with purified precursor solution clearly shows peaks indexed to the (200), (400), and (800) planes, indicating the highly oriented texture. Vertical lines indicate the pattern for orthorhombic SnSe reference (JCPDS 32–1382). d Pole figure of the (400) plane in the SnSe thin film fabricated with purified precursor solution. Colours of the strips indicate the pole density in multiples of random distribution. High intensity at the centre clearly demonstrates the texturing in the thin film