InN material and alloys
The small band gap energy, together with the small effective mass, the large electron mobility and high saturation velocities accompanied by the very high resistance to radiation damage of InN have the potential to lead to a variety of device applications, including high-efficiency multi-junction solar cells, high speed transistors, and light emitters the visible to near-infrared spectral region. Furthermore, the high electron concentrations in the surface accumulation layer can be exploited for gas, chemical and biological sensors and for generation of THz radiation. This symposium covers the most recent developments related to growth and characterization of InN materials and its alloys with GaN and AIN as well as InN heterostructures and device applications.
One of the main materials development challenges is the control of the free electron density in InN and In-rich alloys. Currently the lowest electron carrier densities that have been obtained for thick MBE-grown InN layers are in the mid-10 17 cm -3 range with mobilities around 2500 cm 2/Vs. Most often, however, typical electron densities in InN are in the mid-10 18 cm -3 range, which are obtained on MBE grown films with a thickness of a few hundred nanometres. Similarly, the best MOCVD-grown InN layers exhibit electron mobilities around 1000 cm 2/Vs and carrier densities in excess of 10 18 cm -3.
A related critical issue for the growth of InN and In-rich alloys is the large lattice and thermal mismatch with the available substrates (sapphire, Si, GaAs, SiC) or even bulk GaN. Optimized nucleation techniques and the application of epitaxial lateral overgrowth methods have enabled the realization of GaN layers with dislocation densities in the low 10 6 cm -2 range and the fabrication of LDs (laser diodes) with lifetimes of 10000 hours. Suitable growth methods to reduce the threading dislocation densities in InN materials have to be developed in order to improve the crystalline quality of the InN epitaxial layers for the fabrication of high efficiency devices, like solar cells or light emitters.
Topics do be covered by the symposium include:
- p-type doping of InN and In-rich nitrides
- Dislocation reduction in heteroepitaxy
- Reduction of free electron concentrations
- Radiation damage, point defects & doping
- Different growth approaches: MBE, MOCVD, HVPE, ELO
- InN quantum wells and dots
- InN surfaces and heterostructure interfaces
- Growth of In(Al)N alloys
- InN based devices (e.g. HEMTs, diodes, solar cells)
The Symposium A and RAINBOW workshop TIMETABLE is available on pdf format here
Dr. Filip Tuomisto, Department of Applied Physics, Helsinki University of Technology, Finland
Dr. Pierre Ruterana, CIMAP-ENSICAEN, Caen, France
Prof. Michael Kneissl, Institut für Festkörperphysik, Technische Universität Berlin, Germany
Prof. Yasushi Nanishi, Department of Photonics, School of Science and Engineering, Ritsumeikan University, Japan
The proceedings of this symposium will be published in physica status solidi (c), with selected papers in physica status solidi (a) and (b). All papers will be peer-reviewed.
The deadline for manuscript submission is September 7, 2009. Only on-line submission will be supported: go to http://conferences.wiley-vch.de and choose the proper journal (physica status solidi) and conference (E-MRS 2009 FM, Symposium A, author).
Please see the manuscript preparation guidelines at
General instructions for using the on-line submission can be found here.
The symposium is partially supported by the EU through the RAINBOW ITN Grant agreement N°: PITN-GA-2008-213238. Website: http://rainbow.ensicaen.fr
Department of Applied Physics, Helsinki University of Technology
P.O. Box 1100, FI-02015 TKK Espoo, Finland