Low temperature deposition of TaCN films using pentakis(diethylamido)tantalum

Ta(CN) films were thermally deposited at low temperature (less than or equal to 400 degrees C) using single source pentakis(diethylamido)tantalum (PDEAT) as a precursor. The activation energy of the surface reaction is about 0.79 eV and the maximum deposition rate obtained is about 100 Angstrom/min at 350 degrees C. The resistivity of the as-deposited film decreases as the deposition temperature increases and the minimum value of resistivity obtained is 6000 mu Omega-cm for the sample deposited at 400 degrees C. There is no aging effect of the film resistivity after air exposure. Major chemical elements in the films are identified as Ta, C, and N with some amounts of O by Auger electron spectroscopy (AES). Most of the carbon elements in the film is identified as bonded to Ta by X-ray photoelectron spectroscopy (XPS). The microstructural investigation using high resolution transmission electron microscopy(HRTEM) reveals a nanocrystalline phase with an average grain size of about 30 Angstrom.