Growth of cubic boron nitride on Si(100) by neutralized nitrogen ion bombardment

Abstract

Highly cubic phase and stoichiometric boron nitride films were deposited on Si(100) substrates using a neutralized nitrogen beam and electron beam evaporation of boron. High intensity, focused, and low-energy neutralized nitrogen beam was supplied using a newly developed neutralizer atomic beam ion source (NABS) adapted to a Kaufman-type ion source. The films were grown at substrate temperatures in the range 400–500 °C and a boron evaporation rate of 0.2 A/s. Infrared transmittance spectra of the films showed that a highly cubic phase (80%) was obtained in the area of the focused beam. These films were compared to those obtained using similar conditions but with the NABS disconnected from the ion source, and it was found that the cubic phase content decreases drastically (10%). The results show that the NABS was the determining factor in enhancing the formation of the cubic boron nitride films. Furthermore, the addition of Ar to N, which is reported to increase the momentum transfer and promote the formation of the cubic phase, did not play a significant role when the NABS was used.