Reducing dislocation density in GaN films using a cone-shaped patterned sapphire substrate

Analysis of threading dislocations in void shape controlled GaN re-grown on hexagonally patterned mask-less GaN

“…Over the years, several useful methods have been employed for the growth of epitaxial GaN with improved crystalline quality. Techniques like epitaxial lateral overgrowth (ELOG) [9], pendeo-epitaxy (PE) [4], facet-controlled epitaxial lateral overgrowth (FACELO) [10], patterning of substrates [11,12], multistage growth [13,14], etc. have been shown to be very promising in diminishing the effect of the large dislocation densities that are commonly found in conventionally grown epitaxial GaN layers.…”

Spatial stress distribution and optical properties of GaN films grown on convex shape-patterned sapphire substrate by metalorganic chemical vapor deposition

“…In our previous works [7], we observed strong cathodluminescence from trench regions and these results were attributed to the full coalescence by the lateral growth behavior on trench regions of CSPSS. Further, the results reported by Shin et al have shown that the GaN buffer layer was not formed on convex shapes but only over the flat sapphire region, i.e., flat trench region [12]. On the other hand, a high defect density has been persisted in the GaN grown on the convex region.…”

The GaN-Based Light Emitting Diode Grown on Nanopattern Sapphire Substrate Prepared by Inductively Coupled Plasma Etching

“…In addition, the quality of the film growing on planar sapphire substrate was indeed worse than that using patterned substrate. The results revealed that the film quality will be improved with NPSS and the reason is due to the lateral overgrowth mechanism [10]- [13]. With the reduction of deposit area, it will reduce some dislocations which was caused from GaN/sapphire interface.…”