Centre National de la Recherche Scientifique

Main activity and mission

The LPN (Laboratory for Photonics and Nanostructures) is a fully-owned unit of the Centre National de la Recherche Scientifique (CNRS). The research strategy of the Laboratory, conditioned by its goals and by its nationwide role as a central technological facility, is made possible thanks to the wide spectrum of scientific and technical skills brought together in the Laboratory. It involves multi-disciplinary research that ranges from fundamental to applied physics, in a large variety of research areas including: quantum optics, nonlinear optics, spin electronics, quantum transport, physics of nanostructures, nanomagnetism, photonics, microfluidics, materials science, device physics, optoelectronics, fabrication and processing of materials.

Key expertise

The range of research themes carried out at LPN illustrates the cross-fertilization between research and technology. LPN is present throughout the chain of innovation, from research on novel concepts leading to new functions and research on materials and technologies, to their implementation and to the demonstration of feasibility of new devices. At the same time, the research activities of LPN open new perspectives for potential applications in the fields of quantum information processing, optical communications, all-optical signal processing, high-density information storage, or microfluidics coupled to nanostructures, a field at the interface between physics, chemistry and biology.

Facilities

LPN has one of the 6 major clean room facility supported by the French basic research technology network. The technological service groups together the technological facilities (lithographies, metals and dielectric deposition, etching) located essentially in our clean room. Its primary aim is to develop all the cutting-edge techniques and know-how necessary for the fabrication of the structures and devices studied in the laboratory, and to assist the researchers in the technological aspect of their work. Responding to external requests is also a priority: most of these requests come from our national and international collaborations or are associated with our mission as a National Technological Facility.
The research activities of the group “Elphyse” (Fabrication and Physics of Epitaxial Structures), one of the team of the laboratory, include the growth of III-V alloys and quantum structures, their structural and chemical analysis (down to the subnanometer scale), the study of their electronic, optical and mechanical properties and of their modes of relaxation, and the realization of the first demonstration devices. Main equipments of the group are growth facilities (4 MBE and 1 MOCVD apparatus) and structural characterizations (3 High-Resolution X-Rays Diffraction systems and a TEM 200kV equipped with EDX analysis).

Role in the project :

The major goal is to realize an epitaxially growth of a pn junction in Ge in the same reactor to be used for the subsequent III-V multijonction growth. This will be done by using the recently developed metalorganic source Isobutylgermanium (IBuGe) from Rohm and Haas. Since Ge is a dopant for III-V compounds, it is important to demonstrate that after epitaxial Ge deposition, it will be possible to reduce the Ge content in the subsequent III-V layers.
Furthermore, another more interesting solution will be adressed during the projet which is the growth of SiGe alloys on Si and the subsequent growth of the III-V only by MOCVD. This will be possible by using a new low temperature cracking silicon precursors developped by the compagny Rohm and Haas.