The synthesis of hexagonal wurzite one-dimensional (1D) GaN nanostructures on c-Al2O3 substrates was investigated using a thermal chemical vapor deposition (CVD) process. The diameter of the GaN nanostructures was controlled by varying the growth time using a mixture of GaN powder and Ga metal with the ammonia gas reaction. The morphologies of the GaN nanowires and nanorods were confirmed by fi...

Gallium nitride (GaN) thin films on sapphire substrates were successfully separated and transferred onto Si substrates by pulsed UVlaser processing. A single 600 mJ/cm, 38 ns KrF excimer laser pulse was directed through the transparent substrate to induce a rapid thermal decomposition of the GaN at the GaN/sapphire interface. The decomposition yields metallic Ga and N2 gas that allows separatio...

Magnesium (Mg) is the most commonly used acceptor dopant in gallium nitride (GaN) devices. Acting as a deep acceptor with an activation energy of ~ 200 meV, Mg can introduce electrical and optical complications. Carbon has been demonstrated to be a possible alternative acceptor dopant atom with a lower activation energy [1]. Carbon-doped GaN (GaN:C) samples were homoepitaxially grown on <10-11>...

In order to overcome problems with non-uniform iron (Fe) doping in our GaN layers grown by hydride vapor phase epitaxy, we have optimized the construction of our ferrocene doping channel. By pre-heating the hydrogen carrier gas before entering the hot bubbler, a constant Fe supply could be established. Moreover, losses of the precursor gas in the reactor could be minimized by a re-design of the...

We present a study by transmission electron microscopy (TEM) of the strain state of individual InN quantum dots (QDs) grown on GaN substrates. Moiré fringe and high resolution TEM analyses showed that the QDs are almost fully relaxed due to the generation of a 60° misfit dislocation network at the InN/GaN interface. By applying the Geometric Phase Algorithm to plan-view high-resolution microgra...

Energy disaggregation, namely the separation of aggregated household energy consumption signal into its additive sub-components, bears resemblance to (source) problem and poses several challenges, not only as an ill-posed problem, but also, due unsteady appliance signatures, abnormal behaviour that is usually detected in appliances operation existence noise signal. In this paper, we propose Ene...

The performance of devices fabricated from GaN and related compounds is strongly affected by the resistances caused by electrical contacts. To avoid excessive heating resulting in a failure of the device, speciŽc contact resistances less than ,10 Wcm for light-emitting diodes (LEDs) and less than ,10 Wcm for laser diodes are required. This applies in particular to ohmic contacts on p-doped GaN ...

The UV-to-visible rejection ratio is one of the important figure of merits of GaN-based UV photodetectors. For cost-effectiveness and large-scale fabrication of GaN devices, we tried to grow a GaN epitaxial layer on silicon substrate with complicated buffer layers for a stress-release. It is known that the structure of the buffer layers affects the performance of devices fabricated on the GaN e...