Epitaxial TiN layers, 0.3 μm thick, are grown on MgO(001) in the absence of applied substrate heating using very high flux, low-energy (below the lattice atom displacement threshold), ion irradiation during reactive magnetron sputter deposition in pure N2 discharges. High-resolution x-ray diffraction, reciprocal lattice maps, and transmission electron microscopy analyses reveal that the TiN(001) films grow with an (001)TiN||(001) MgO and TiN||MgO orientation relationship to the substrate. The layers are fully coherent with no detectable misfit dislocations. For comparison, TiN/MgO(001) films grown at temperatures of 700-850 °C under similar conditions, but with no intentional ion irradiation, are fully relaxed with a high misfit dislocation density. Thus, the present results reveal that intense low-energy ion irradiation during film growth facilitates high adatom mobilities giving rise to low-temperature epitaxy, while the low growth temperature quenches strain-induced relaxation and suppresses misfit dislocation formation.
Bibliographical noteFunding Information:
This research was supported by the U.S. Department of Energy, Division of Materials Science , grant DEFG02-91ER45439 through the University of Illinois Frederick Seitz Materials Research Laboratory (FS-MRL) and by Priority Research Centers Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009-0093823). We appreciate the use of the facilities at the FS-MRL Center for Microanalysis of Materials, which is partially supported by DOE, at the University of Illinois.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry