c-BN film was synthesized using ME-ARE on Si substrate. The deposition process was optimized via the Taguchi method. The optimized conditions were as follows: substrate temperature, anode (plasma) current, Ar/N-2 ratio, pulse frequency, duty frequency, bias voltage and deposition time were 500degreesC, 15A, 3, 1 kHz, 50%, -130V and 15 min, respectively. The cross-sectional TEM observation revealed that the c-BN films with a thickness of 100nm similar to300nm were composed of two layers, a columnar h-BN layer with a thickness of 30nmsimilar to40 nm normal to Si substrate and a c-BN structure.