Fast Atom Diffraction applied to real time monitoring of epitaxial growth – GIFAD-II

Molecular beam epitaxy (MBE) is the method of choice for producing high performance devices for microelectronic and optoelectronic applications. The success of MBE lies in part in the use of RHEED (Reflection High Energy Electron Diffraction) for the real time monitoring of the growth. Yet, RHEED bears some limitations that can be incompatible with the specifications imposed by new materials such as high-k dielectrics, large band gap semiconductors and organic layers, the latter being extremely fragile with respect to electron irradiation.
In 2003, the ISMO group discovered the diffraction of fast atoms from surfaces, while the surface science community predominantly uses electron diffraction techniques. This work has been very fruitful since, following an extensive study of this new phenomenon, a patent has been filled for a new method for surface analysis. Since 2007, The ISMO has been working in collaboration with the group at INSP in order to validate this technique on materials relevant for microelectronics. This technique soon appeared as a powerful alternative to RHEED as it provides similar information but with a much greater sensitivity to the top most layer and with superior analytical power. A new technique, named GIFAD for Grazing Incidence Fast Atom Diffraction, was born with two main applications: real-time diagnostics or in-line quality control in production MBE and fundamental studies in surface science.
Funding was obtained for laboratory demonstration of GIFAD, the technical objective of the current project is to achieve its technological maturation so that an optimized prototype can be made operational in a production environment and simultaneously be considered as an effective solution for research. The main stake consists in optimizing the ion source, the heart of GIFAD, in order to achieve an effective real-time capability and take full advantage of its analytical power.
The long time partners, ISMO, INSP and FIST SA, are used to work together and hold complementary expertise. The group at ISMO is specialized in particle-surface interactions and is the inventor of GIFAD; it will be in charge of optimizing the ion source and developing an analytical model for the diffraction data. The team at INSP has an extensive expertise in the MBE growth of semiconductors; it will take on the qualification of GIFAD as a relevant and effective tool for MBE. Finally FIST SA, specialized in Intellectual Property and Technology and Innovation transfer, will be responsible for the valorization procedure.