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The dual-source atmospheric-pressure chemical vapor deposition of group IVb metal phosphide films from tetrakisdimethylamido(metal) and cyclohexylphosphine precursors is presented. Deposition took place at low temperatures (<500 °C), and nitrogen and carbon contamination of the films was negligible. The films had typical stoichiometric metal phosphide properties of high electrical conductivity, hardness, and chemical resistivity.

Atmospheric pressure chemical vapor deposition of titanium phosphide coatings was achieved on glass substrates from the reaction of TiCl4 and RPH2 (R = t-Bu, Ph, Cy^hex) at 450−550 °C. The coatings show good uniformity, surface coverage, and adherence; they passed the Scotch brand tape test and could not be scratched with a brass scalpel. The leading edge of the titanium phosphide films was a deep blue while the bulk of the film was reflective and silver. Growth rates were on the order of 1 μm min^-1 at 550 °C. The films were crystalline, single phase with a hexagonal cell of a = 3.49(1) Å and c = 11.70(1) Å. Scanning electron microscopy (SEM) revealed surface morphologies consistent with an island growth mechanism. X-ray photoelectron spectroscopy (XPS) binding energy shifts were at 454.6 eV for Ti2p and at 128.6 eV for P2p. Energy-dispersive X-ray analysis (EDXA) and electron probe studies gave elemental ratios that were in agreement indicating in most cases slightly P-rich films, TiP1.2, with negligible chlorine incorporation. Raman spectra exhibited bands at 245, 320, and 410 cm^-1. Sheet resistance measurements showed typically 10−120 mΩ cm, indicating good conductivity. Rutherford backscattering showed a bulk composition of TiP1.2. Optically, the films showed high reflectivity at 1000 nm and showed 5−25% total transmission from 300 to 800 nm. Contact angle measurements were in the range 40−50° for the as made films these showed little change after 30 min of irradiation at 254 nm. All of the films showed negligible photocatalytic activity in the destruction of an overlayer of stearic acid.