Growth of thick and flat high quality GaN using nano-column compliant layers
Lead Research Organisation:
University of Nottingham
Department Name: Sch of Physics & Astronomy
Abstract
This research will primarily develop a novel technique to grow a high volume of high quality gallium nitride for use in optoelectronic, microelectronic and biomedical devices.It is currently very difficult to produce large single crystal gallium nitride due to the high pressures and temperatures required, and this is inhibiting the wide uptake of this disruptive material technology. Instead, the technique involved in this proposal uses a high density of minature columns with dimensions on the nano-scale to initiate the chemical growth of a large crystal from a crystal of another material that has a different crystal structure. The columns reduce the problems associated with the different crystal structures and has the potential to produce high quality gallium nitride at relatively low cost.The research will determine the optimum column size and the best conditions for the crystal growth by theoretical modelling and experimentation. Three different complementary growth techniques at the universities of Nottingham and Bath will be used, and the advanced characterisation techniques and expertise at Bristol University will provide essential feedback and understanding of the nanostructures to the growth personnel.
Organisations
Publications
Cherns D
(2008)
Defect-controlled growth of GaN nanorods on (0001)sapphire by molecular beam epitaxy
in Applied Physics Letters
Cherns D
(2008)
Defect reduction in GaN/(0001)sapphire films grown by molecular beam epitaxy using nanocolumn intermediate layers
in Applied Physics Letters
D Cherns
(2009)
Nanorods as a precursor for high quality GaN layers
Foxon C
(2009)
A complementary geometric model for the growth of GaN nanocolumns prepared by plasma-assisted molecular beam epitaxy
in Journal of Crystal Growth
HorĂ¡k L
(2008)
X-ray in-plane scattering investigation of GaN nanorods
in Journal of Applied Physics
Meshi L
(2008)
The reduction of threading dislocations in GaN using a GaN nanocolumn interlayer
in physica status solidi c
Description | Using Molecular Beam Epitaxy (MBE), we have shown that it is possible to grow almost exclusively defect free Gallium Nitride Nanocolumns and then subsequently coalesce these columns into a continuous film during a single growth run. The films showed a reduced defect density with respect to films grown in the conventional manner. We also produced a geometrical model to help explain the growth modes that we observed. Furthermore, we idenified a previously unidentified defect in a small proportion |
Exploitation Route | As a basis for lower defect density substrates for the growth of Gallium Nitride devices. |
Sectors | Electronics,Energy |