EXPECTED WORK

Two of the reasons for this so far limited efficiency is the quality of the nitride material and the technology employed for fabricating the diodes. We have created an academic consortium which, around CEA-LETI, can address the different issues at stake, in order to develop a true technology stream in this field. One of the issues concerns the structural quality of the epitaxial layers, dislocations being non-radiative defects that kill the internal efficiency of the LED. Within the consortium, we are in charge of developing new and optimized template layers, i.e. the epitaxial layer nucleated on the surface of the sapphire substrate, since an important part of the defects in the LEDs arise from this nucleation layer. To address this point, we will develop new and original methods for the deposition of AlN and AlGaN templates: reactive sputtering, co-sputtering (for alloy templates) and Pulsed Laser Deposition (PLD). The layers will be characterized on the Nano-Characterization Platfom of LETI and will be evaluated according to the electro-optical properties of the LEDs structures that will be epitaxially grown on top of these templates.

The ideal candidate will hold a PhD in material science, physics, or chemistry, and ideally a working knowledge of optoelectronics, material characterization, and III-nitrides epitaxy. During this post-doc, the candidate will enjoy a state-of-the art scientific and technological environment.