INITIAL STAGES OF GROWTH OF BaMgF₄ ON (111)-SILICON

ABSTRACT

We have grown BaMgF₄ films on (111)-oriented Si substrates with existing native oxide layers using molecular beam epitaxy. The early stages of growth were studied through the application of x-ray photoelectron spectroscopy measurements on interrupted growth runs without exposing films to atmosphere. Exposure of the Si substrates to the BaMgF₄ vapor at a substrate temperature of 950°C resulted in the formation of silicate species and a reduction of the SiO₂ species on the substrate. Subsequent growth onto this silicate buffer layer resulted in highly textured (020)-oriented BaMgF₄ films, as evidenced by x-ray diffraction studies.

Keywords::

• Thin films
• x-ray photoelectron spectroscopy
• interface chemistry
• barium magnesium fluoride

ACKNOWLEDGMENTS

We acknowledge the Materials Characterization Center of the University of Puerto Rico for the use of their x-ray diffraction facilities, and Francisco Santiago for helpful discussions. We also acknowledge the work of the machine and electronic shops of the College of Natural Sciences.