Effect of annealing on dielectric constant of boron carbon nitride films synthesized by plasma-assisted chemical vapor deposition

Abstract

Polycrystalline boron carbon nitride (BCN) films are synthesized by plasma-assisted chemical vapor deposition. The dielectric constant is estimated from the accumulation region of capacitance–voltage characteristics of Cu/BCN/p-Si samples. It is found that the dielectric constant of the BCN film is reduced by annealing at 400 °C. The BCN film before and after annealing is characterized by Fourier transform infrared absorption measurements. The infrared absorption intensities due to the C–H and C=C bonds decrease after annealing. It is suggested that the C–H and C=C bonds are undesirable to obtain a low dielectric constant. A dielectric constant as low as 2.1 is achieved for the BCN film which is treated by annealing process.