Molecular Beam Epitaxy of III-Nitride nanowires

MBE Riber Compact 12

Contacts: Laurent Travers , Martina Morassi and Noelle Lebeau-Gogneau  

The C12 is a small Plasma-Assisted MBE (PA-MBE) reactor, very user-friendly and cost-effective, dedicated to the epitaxy of Nitride materials (AlN, InN, GaN and their alloys). As the name suggests, the active N species are provided by a radio-frequency (RF) plasma source. In this source, N₂ gaseous molecules are injected in a PBN cavity and are resonantly excited and dissociated by a 13.56 MHz RF electromagnetic wave. The flux of active N species is adjusted by varying the N₂ flux and the RF power. 

The chamber allows to grow on 1-2" substrates (1" uniformity) and is equiped with:

• Three quasi-Knudsen effusion cells for metallic species: Ga, Al and In
• Two effusion cells for dopant species: Si and Mg
• One Riber RF plasma source
• One graphite-based substrate heater allowing for reaching 800-850 °C
• One interfaced reflective high-energy electron diffraction (RHEED) apparatus for real-time growth monitoring

The know-how associated to this MBE machine is strictly associated to its research activity (see here) and involves the epitaxy of GaN and In_xGa_1-xN/GaN nanowires on Si(111), SiO₂, SiNx, transferred graphene and silica. Present efforts concern NWs doping optimization, and the machine is suitable also for growing planar III-N heterostructures.

Figure: (a) Photo of our Riber C12 MBE and its schematic representation (b). (c) Hot graphite filament of the sample heater.