molecular beam epitaxy abbr., MBE (rus. эпитаксия, молекулярно-лучевая abbr., МЛЭ; МПЭ) — overgrowth of semiconductor monocrystalline layers on a substrate, involving the deposition of evaporated components onto the heated monocrystalline substrate with simultaneous interaction between them.

Description

MBE is a form of epitaxy as a nanotechnological method to produce semiconductor heterostructures.

Every MBE heater has a crucible, which is a source of a film component. The pressure at the heaters is controlled by evaporation pressure, which must be sufficient to form the appropriate molecular beams. To transfer the evaporant to the substrate, a high vacuum is induced. The heaters are located so that the beam intensity distribution maxima cross within the substrate plane. The range of temperatures at the heaters and at the substrate enables the production of films with complex chemistry. The substrate temperature going up to a certain limit usually leads to a better quality of epitaxial layers. In addition, growth is controlled by damper valves between the heater and the substrate, which shut in or resume the molecular beams on the substrate. The MBE units have locks for the sample change and may include the equipment for film analysis by in situ reflection-electron diffraction, mass spectrometry and auger electron spectroscopy with the option of analysing the auger spectra of disperse ions. Mask-based MBE grows the local structure of the different topography on the surface.

Illustrations

<p>Molecular beam epitaxy unit design.</p>

Molecular beam epitaxy unit design.


Author

  • Gusev Alexander I.

Source

  1. Gusev A. I. Nanomaterials, Nanostructures, and Nanotechnologies (in Russian) // Fizmatlit, Moscow (2007) - 416 pp.