EPITAXIAL-GROWTH OF TIN FILMS ON (100) SILICON SUBSTRATES BY LASER PHYSICAL VAPOR-DEPOSITION

We report epitaxial growth of TiN films having low resistivity on (100) silicon substrates using pulsed laser deposition method. The TiN films were characterized using x-ray diffraction, Rutherford backscattering, four-point-probe ac resistivity, high resolution transmission electron microscopy and scanning electron microscopy techniques and epitaxial relationship was found to be [100] TiN parallel-to [100] Si. TiN films showed 10%-20% channeling yield. In the plane, four unit cells of TiN match with three unit cells of silicon with less than 4.0% misfit. This domain matching epitaxy provides a new mechanism of epitaxial growth in systems with large lattice misfits. Four-point-probe measurements show characteristic metallic behavior of these films as a function of temperature with a typical resistivity of about 15 mu-OMEGA cm at room temperature. Implications of low-resistivity epitaxial TiN in silicon device fabrication are discussed.