Single crystal titanium nitride epitaxial on silicon

Abstract

Epitaxial growth of films on single crystal substrates having a lattice mismatch of at least 10% through domain matching is achieved by maintaining na.sub.1 within 5% of ma.sub.2, wherein a.sub.1 is the lattice constant of the substrate, a.sub.2 is the lattice constant of the epitaxial layer and n and m are integers. The epitaxial layer can be TiN and the substrate can be Si or GaAs. For instance, epitaxial TiN films having low resistivity can be provided on (100) silicon and (100) GaAs substrates using a pulsed laser deposition method. The TiN films were characterized using X-ray diffraction (XRD), Rutherford back scattering (RBS), four-point-probe ac resistivity, high resolution transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques. Epitaxial relationship was found to be <100> TiN aligned with <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 TiN films as a function of temperature with a typical resistivity of about 15 .mu..OMEGA.-cm at room temperature.

Dependencies are inferred from the claim text.