Thermal Laser Epitaxy
Thermal laser epitaxy is a physical vapor deposition technique. It uses single element sources that are heated by lasers beams in order to thermally evaporate the source material. Because the laser beams can be made with almost arbitrary power density, extremely high temperatures are possible. This allows for the evaporation of practically all elements of the periodic table with the same setup. Therefore, TLE is a very versatile deposition technique.
The chamber requires only simple holders for the sources and substrates, because the energy sources are placed outside the vacuum chamber. This benefits system simplicity and sample purity. Moreover, the direct local heating of targets in TLE ensures that only the evaporating surfaces are heated. This minimizes contamination. TLE is compatible with a range of background gasses up to pressures of 10-2 mbar.
In summary, TLE is a highly flexible deposition technique that can be used to grow almost any material with ultrahigh purity.
TLE is especially interesting for materials science in the fields of quantum computing, strongly correlated electron systems, novel material synthesis, topological materials, and energy research.
Advantages and challenges of TLE
- Epitaxy with almost all elements
- Ultrahigh purity
- In situ source and sample transfer
- High throughput due to high ramp rates
- Compatibility with highly reactive atmospheres
- Low operating costs
TLE has some intrinsic challenges as well. Based on our long experience with TLE setup we have developed patent-protected solutions for:
- Growth stability
- Uniform melting of the sources
- Entrance window protection
- Combining sources with high and low temperatures