PREFERRED GROWTH OF EPITAXIAL TIN THIN-FILM ON SILICON SUBSTRATE BY PULSED-LASER DEPOSITION

Epitaxial TiN thin films on silicon substrates were prepared by pulsed excimer laser (KrF, 34 ns) ablation of a hot-pressed TiN target in ni trogen gas atmosphere. X-ray diffraction (XRD) showed that the preferr ed orientations of TiN thin films did not change with substrate temper atures, nitrogen gas pressure and film thickness; however, they did ch ange with the orientations of substrates. The epitaxial orientation re lationships between high-quality epitaxial TiN thin films and silicon substrates [242] TiN parallel to [242] Si, (111) TiN parallel to( 111) Si and [311] TiN parallel to [311] Si, (100) TiN parallel to(100) Si. The full-width at half-maximum (FWHM) of the rocking curve of XRD and the minimum channelling yield of Rutherford backscattered spectroscop y (RBS) of the epitaxial TiN thin film were estimated to be 0.3 degree s and 7.3%, respectively, indicating excellent crystalline quality of the grown film. X-ray photoelectron spectroscopy confirmed that the bi nding energies of Ti2p3/2 and N1s core levels in epitaxial thin film w ere 455.2 and 397.1 eV, respectively, corresponding to those of TiN bu lk. By calibrating the RBS spectra, the chemical composition of TiN th in films was found to be titanium-rich. The typical surface roughness of TiN thin film observed by scanning probe microscopy was about 1.5 n m. (C) 1998 Chapman & Hall.