Growth of cubic boron nitride thin films by a field-ionization source-assisted pulsed laser deposition

Abstract

Cubic boron nitride (cBN) thin films have been deposited on silicon (100) substrate using ArF pulsed excimer laser for ablating hexagonal boron nitride (hBN) targets and a field-ionization source for activating N 2. The structure and composition of the films have been measured by Fourier transformation infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis and Auger electron spectroscopy (AES). The FTIR transmittance spectrum shows that there are a strong absorption peak at 1095.8 cm −1 corresponding to cBN and a very weak absorption band at 1380 cm −1 corresponding to hBN. The XRD pattern shows that there is a peak at 43.30° corresponding to the cBN (111) face. These results show that the films are mainly cBN including a small amount of hBN. AES depth-profiling experiments show that the relative atomic ratio of N to B in the films is obviously increased by using a field-ionization source of about 700 V during the deposition process.