C2N - Marcoussis Campus - epitaxy facilities are installed in a 350 m2 clean-room environment. It is connected to the rest of the clean room, allowing interactions with processing technologies. Both advanced growth technologies, molecular beam epitaxy (MBE) and metalorganic vapor phase epitaxy (MOVPE) are available. Each of these techniques has specific characteristics for specific needs:
MBE operates under ultra-vacuum conditions. The growth chamber is cooled with liquid nitrogen. Pure elemental solid sources are thermally evaporated. With adequate pumping (turbomolecular or cryo pumps), gas sources can be also installed. The key features of MBE:
MOVPE can operate between 20 and 760 Torrs. The gas sources are metalorganic precursors or hydrides. Hydrogen is commonly used as carrier gas. Hydrides are highly toxic and require detection and security systems. The key features of MOVPE
The C2N - Marcoussis Campus - growth equipements consist of 4 MBE and 1 MOVPE systems, exclusively devoted to III-V semiconductor growth. A lot of different alloys and structures are fabricated. The physics of crystal growth and the material characteristics are studied by means of in-situ (STM, RHEED, reflectometry) or ex-situ analyses (AFM, TEM, XRD, optical spectroscopies, transport).
With these growth techniques, one can obtain structures with quantum confinement in 1 (quantum wells, heterointerfaces) , 2 (quantum wires lateral super-lattices) or 3 (quantum dots) directions.
The growth of these epitaxial structures is dedicated to many basic, as well as applied research activities. Epitaxy at C2N supplies samples for national and international collaborations or projects. In particular, epitaxy is strongly involved in device activities including lasers and detectors for telecommunications, all-optical devices, transistors. Other important topics where epitaxy as a significant role are: spintronic, 2D electron gas, physics of nanostructures, photonic crystals, microcavities, ...