Leakage Current Characteristics Of Thick Cubic Boron Nitride Films Deposited On Titanium

Thick cubic and sp(2)-bonded boron nitride (cBN and sp(2)BN) films are deposited on Ti substrates by plasma jet enhanced chemical vapor deposition using the chemistry of fluorine, and their direct current-voltage characteristics are studied for Ni-BN-Ti capacitor structures. The resistivity of the cBN film measured at room temperature is of the order of 10(8) Omega cm, which is three to four orders of magnitude lower than that of the sp(2)BN film. At high electric fields, Frenkel-Poole emission dominates the conduction of the sp(2)BN film, while thermionic emission is better able to describe the conduction of the cBN film at temperatures up to 473 K. A lower leakage current indicates lower densities of carriers and trap sites associated with defects, suggesting that a higher-quality cBN film with higher crystallinity and stoichiometry is potentially promising as an ultrahard dielectric material in high temperature condition. Published by AIP Publishing.