In situ monitoring techniques during MBE growth of nanostructures

Molecular Beam Epitaxy (MBE), one of the most established fabrication process for nanostructures with precise control at atomic level of morphology, thickness and chemical composition, has demonstrated recently extended capabilities for the selfassembly and self organization of low dimensional structures such as Quantum Dots (QD) and Quantum Wires (QW). Its main advantage is the compatibility of this process with a wide range of in situ monitoring and control techniques. In this talk, an overview of MBE in-situ monitoring techniques at IMM will be presented and will be illustrated with recent results in the fields of highly mismatched epitaxial systems, self-assembling of III-V semiconductors low dimensionality structures such as QDs, QWs and new structures named Q-rings, applied to the fabrication of diode laser devices. Among those techniques, we will emphasize less known ones such as in situ, real time accumulated strain optical measurements in combination with growth front light scattering. Also results will be shown on anisotropic surface tension and interface strain measurements using laser deflection, together with Surface Reflectance Anisotropy that provides accurate information on surface stoichiometry, surface segregation effects. QDs and QW selfassembly study through direct monitoring of strain relaxation process will be presented as an example of these techniques capabilities .