This dataset provides the experimental data used to generate figure 3 in the paper entitled "Monolithic multiple colour emission from InGaN grown on patterned non-polar GaN".
The cathodoluminescence (CL) data discussed and presented in the paper was recorded using a variable pressure field emission scanning electron microscope (SEM, FEI Quanta 250) which is equipped with a custom-built CL hyperspectral imaging system. The CL system collects the emitted light at an angle of 45° with respect to the incident electron beam using a Cassegrain reflecting objective. The light is then dispersed using a 125 mm focal length spectrograph (Oriel MS125) and detected using an electron-multiplying charge-coupled device (Andor Newton). As the electron beam scans across the sample surface, a whole CL spectrum is recorded per pixel building up the 3D hyperspectral data set. 2D CL images can then be extracted from the hyperspectral data set, such as peak energy, intensity or half width.
Abstract of the paper:
A novel overgrowth approach has been developed in order to create a multiple-facet structure consisting of only non-polar and semi-polar GaN facets without involving any c-plane facets, allowing the major drawbacks of utilising c-plane GaN for the growth of III-nitride optoelectronics to be eliminated. Such a multiple-facet structure can be achieved by means of overgrowth on nonpolar GaN micro-rod arrays on r-plane sapphire. InGaN multiple quantum wells (MQWs) are then grown on the multiple-facet templates. Due to the different efficiencies of indium incorporation on non-polar and semi-polar GaN facets, multiple-colour InGaN/GaN MQWs have been obtained. Photoluminescence (PL) measurements have demonstrated that the multiple-colour emissions with a tunable intensity ratio of different wavelength emissions can be achieved simply through controlling the overgrowth conditions. Detailed cathodoluminescence measurements and excitationpower dependent PL measurements have been performed, further validating the approach of employing the multiple facet templates for the growth of multiple colour InGaN/GaN MQWs. It is worth highlighting that the approach potentially paves the way for the growth of monolithic phosphor-free white emitters in the future.
Data available on publication of related research output