Semiconducting nanostructured copper sulfide thin films from bidentate copper(ii) complexes of N-(dialkylcarbamothioyl)-nitrosubstituted benzamides by chemical vapour deposition

Abstract

Copper(II) complexes of various N-(dialkylcarbamothioyl)-nitrosubstituted benzamide [dialkyl = di-n-butyl (1a, 2a); hexyl, methyl (3a); butyl, ethyl (4a)] have been synthesized and characterized by elemental analysis, IR spectroscopy and atmospheric pressure chemical ionization-mass spectrometry (MS-APCI). The molecular structure of the complex 2a was determined by single-crystal X-ray diffraction. These complexes were used as single-source precursors for the deposition of copper sulfide thin films by aerosol assisted chemical vapour deposition (AA-CVD) at 350 °C. The powder X-ray diffraction (p-XRD) patterns of the thin films of complexes 3a and 4ashowed the deposition of rhombohedral digenite Cu9S5 phase, and complex 1a deposited monoclinic roxbyite Cu7S4 phase at 350 °C with spherical crystallites. Complex 2a deposited orthorhombic anilite Cu7S4 phase with spherical crystallites. The degree of roughness of the film surface was determined by atomic force microscopy (AFM). The scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDXA) results showed the uniform distribution of copper sulfide in the films, which makes them useful semiconducting materials on a structured surface.