Raman and photoluminescence characterization of focused ion beam patterned InGaN/GaN multi-quantum-wells nanopillar arrayEffects of growth interruption on the optical and the structural properties of InGaN/GaN quantum wells grown by metalorganic chemical vapor deposition GaN nanopillar and nanostripe arrays with embedded InGaN / GaN multi-quantum wells ͑MQWs͒ were fabricated by holographic lithography and subsequent reactive ion etching. Etch related damage of the nanostructures was successfully healed through annealing in NH 3 /N 2 mixtures under optimized conditions. The nanopatterned samples exhibited enhanced luminescence in comparison to the planar wafers. X-ray reciprocal space maps recorded around the asymmetric ͑1015͒ reflection revealed that the MQWs in both nanopillars and nanostripes relaxed after nanopatterning and adopted a larger in-plane lattice constant than the underlying GaN layer. The pillar relaxation process had no measurable effect on the Stokes shift typically observed in MQWs on c-plane GaN, as evaluated by excitation power dependent photoluminescence ͑PL͒ measurements. Angular-resolved PL measurements revealed the extraction of guided modes from the nanopillar arrays.

Articles you may be interested inInfluence of vicinal sapphire substrate on the properties of N-polar GaN films grown by metal-organic chemical vapor deposition Appl. Phys. Lett. 105, 082114 (2014); 10.1063/1.4894632 Growth and characterization of N-polar GaN films on SiC by metal organic chemical vapor deposition J. Appl. Phys. Influence of gallium supersaturation on the properties of GaN grown by metalorganic chemical vapor deposition J. Appl. Phys. Influence of the substrate misorientation on the properties of N-polar GaN films grown by metal organic chemical vapor deposition Influence of buffer layer and growth temperature on the properties of an undoped GaN layer grown on sapphire substrate by metalorganic chemical vapor deposition

N-polar ð0001 1Þ GaN templates were patterned using holographic lithography to create nanopillar (NP) and nanostripe (NS) arrays. InGaN and GaN was subsequently regrown on the patterned wafers by metalorganic chemical vapor deposition (MOCVD). The impact of changes in V/III ratio and growth temperature were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence (PL). Highly selective growth of InGaN and GaN on planes close to the f10 1 10g m-planes was observed over a wide range of growth conditions as well as different facet formation compared to regrowth on Ga-polar (0001) NP and NS arrays.

GaN nanopillar and nanostripe arrays with embedded InGaN/GaN multi quantum wells (MQWs) were fabricated from planar wafers with different quantum well widths using holographic lithography and subsequent reactive ion etching. Although the etching process led to a reduction in the MQW related luminescence, the etch related damage was successfully healed through annealing in NH 3 /N 2 mixtures under optimized conditions, and the annealed nanopatterned samples exhibited enhanced photoluminescence (PL) compared to the planar wafers. Angular-resolved PL measurements revealed extraction of guided modes from the nanopillar and nanostripe arrays.

No abstract