Epitaxial growth mechanism of chlorinated copper phthalocyanine on KCl surfaces

Powdered chlorinated copper phthalocyanine (ClCuPc) was sublimated to a thickness of 400 Å onto KCl cleavage faces, and the films were examined with electron microscopy and diffraction. The ClCuPc crystals grew with S-orientation in which the molecules stand on the substrate, and with P-orientation in which the molecules lie parallel to the substrate. At the substrate temperature of 250°C, the S-orientation became dominant with increasing deposition rates. The growth mechanism of the crystals with these orientations is discussed on the basis of the adsorption energy of ClCuPc on a KCl surface.