Oxide/silicon interface structure and composition

We have determined the structure of the interface between an epitaxial crystalline oxide and silicon, including the sub-Å distortions of the silicon and oxide caused by the strain of connecting the two crystal lattices at the interface.

To achieve this result, we combined several techniques:

  • Precise MBE growth of BaO
  • Synchrotron X-ray diffraction
    • X-rays shine from the left
    • Scatter from the interface
    • Form on image on a CCD
  • First principles theory
    • Model interface structure

We find that an extra atomic layer of oxygen is incorporated at the interface, changing the band offset.

theory_experiment_loop

Friday, December 13, 2013