Template-nonlithographic nanopatterning for site control growth of InGaN nanodots

Abstract

A site-control nucleation and growth approach for dense InGaN nanodots has been demonstrated on the surface of GaN using a nonlithographic nanopatterning technique by metal organic chemical vapor deposition. Shallow nanopore arrays with a depth of ∼15nm are created by inductively coupled plasma etching in the GaN surface using anodic aluminum oxide films as etch masks. The nanopores are found to be the preferential sites for the InGaN nanodot formation. Uniform InGaN nanodot arrays with a density as high as 1010∕cm2 as defined by the nanopores in GaN were observed on the surface. A strong photoluminescence (PL) emission peak near 2.8eV is observed from the InGaN nanodots. The temperature dependence of PL shows the enhanced carrier localization with higher activation energy in the InGaN nanodots when compared to the InGaN thin layer grown simultaneously on the nonpatterned GaN surface.

GaN-based light emitting diodes with large area surface nano-structures patterned by anodic aluminum oxide templates

“…Pore diameter and pore spacing can be controlled in the ranges of 10-300nm and 25-500 nm respectively through proper selection of the type and concentration of electrolyte, anodic voltage and temperature [10][11][12] . The nanoporous AAO membranes can be used as templates for fabricating various nano-scale structures including nanowires 13 , imprint mold 14 , evaporate mask 15 GaN-based materials and devices have attracted increasing interests such as the nano-scale lateral epitaxial overgrown GaN layer 17 , the fabrication of nanopore and nanodot arrays [18][19][20][21] , the formation of nano-scale surface of GaN 22 . Keunjoo Kim et al 22 fabricated anodic alumina for samples of an Al foil template and an Al deposited film and formed nanopores on the p-GaN surfaces of InGaN/GaN multi-quantum-well (MQW) lightemitting diodes (LEDs).…”

Self-Organized and High Aspect Ratio Nanoporous Zinc Oxide Prepared by Anodization

“…Nanostructured ZnO has been receiving particular attention in recent years due to its great potential applications in electronic, optoelectronic and sensing devices (1)(2)(3). Considerable efforts have been done to fabricate ZnO nanowires, nanorods and nanotubes with diameters ranging from several ten to several hundred nanometers, and lengths from hundreds of up to several micrometers by using catalytic growth through physical or chemical vapor deposition and wet chemical methods (4)(5)(6).…”

Controlled Growth of Ordered Nanopore Arrays in GaN

“…Porous semiconductors have attracted considerable attention for their potential applications in sensing, catalysis, and as templates for lattice-mismatched heteroepitaxy. − With controlled positioning of pores with diameters in the range of nanometers comes the promise of devices that manipulate ionic and molecular transport, , “nanocontainers” that can be employed in “smart” extraction and gene delivery systems, , and the assembly of “quantum fortresses” within semiconductors. , The III-nitrides are interesting materials for nanopore applications as they are mechanically robust and biologically compatible, as well as electrically and optically active . Nanopore structures have been previously fabricated within GaN by reactive ion etching (RIE) and inductively coupled plasma (ICP) etching, − anodization and wet chemical etching, , and growth of porous particles and nanowires. , Direct RIE and ICP etching of nanopores results in damaged surfaces, thus degrading the quality of electrically active interfaces. Chemical etching and anodization methods result in nanopores with variations in uniformity and little control over position.…”