| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016) | |
| Thin Films | Tuesday Sessions |
| Session TF-TuM |
| Session: | Nanostructured Surfaces & Thin Films II |
| Presenter: | Haoning Li, Tyndall National Institute |
| Authors: | M. Conroy, Pacific Northwest National Laboratory H. Li, Tyndall National Institute V. Zubialevich, Tyndall National Institute J. Holmes, Tyndall National Institute P. Parbrook, Tyndall National Institute |
| Correspondent: | Click to Email |
Nanostructured semiconductors have a clear potential for improved optoelectronic devices, such as high-efficiency light-emitting diodes (LEDs). However, most arrays of semiconductor nanorods suffer from having relatively low densities (or “fill factors”) and a high degree of nonuniformity, especially when produced by self-organized growth. Ideally an array of nanorods for an optoelectronic emitter should have a fill factor close to 100%, with uniform rod diameter and height. In this paper we present a “space-filling” approach for forming defect-free arrays of AlN nanorods, whereby the separation between each rod can be controlled to 5 nm due to a self-limiting process. These arrays of pyramidal-topped AlN nanorods formed over wafer-scale areas by metal organic chemical vapor deposition provide a defect-free semi-polar top surface, for potential optoelectronic device applications with the highest reported fill factor at 98%. We then applied this method to GaN, in particular investigating the desorption factor that was not an issue for the AlN growth. Here we show that the etched nanorods change morphology during the annealing step even before additional GaN is deposited, forming 6 non-polar side walls.