Effects of Ion Beam Energy on the Formation of Cubic Boron Nitride Thin Films by Pulsed Nd:YAG Laser Deposition

Cubic boron nitride (cBN) thin films are synthesized on Si(100) substrates by a pulsed neodymium: yttrium-aluminum-garnet (Nd:YAG) laser deposition method using an ion beam in order to enhance the synthesis of the cBN phase. The deposited films were characterized by a Fourier transform infrared (FT-IR) measurement method. When a pure N2 ion beam is used, some absorption peaks for hexagonal boron nitride (hBN) are visible, but the peak for cBN cannot be observed. When argon(Ar) gas is mixed with the reactant nitrogen(N2) gas, the peak at 1050 cm-1 for cBN appears, in addition to those of hBN. When the ion-beam current and voltage is increased to 20 mA and 400 V, the absorption peak intensity for cBN increases, and that of hBN disappears. These results suggest that nitrogen and argon ion bombardment plays an important role in the formation of cBN films.