Dielectric Constant of Boron Nitride Films Synthesized by Plasma-Assisted Chemical Vapor Deposition

Polycrystalline boron nitride (BN) films are synthesized by plasma-assisted chemical vapor deposition using BCl 3 and N 2 as source gases. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared absorption (FTIR) measurements are carried out to characterize the BN films. Capacitance–voltage (C–V) characteristics are measured for Au/BN/p-Si samples. The dielectric constant is estimated from the capacitance in the accumulation region and the film thickness. A dielectric constant as low as 2.2 is achieved for the BN film. It is found that incorporation of carbon atoms into BN films is effective in reducing the dielectric constant.