Fabrication of ZnO photonic crystals by nanosphere lithography using inductively coupled-plasma reactive ion etching with CH4/H2/Ar plasma on the ZnO/GaN heterojunction light emitting diodes

Abstract

This article reports fabrication of n-ZnO photonic crystal/p-GaN light emitting diode (LED) by nanosphere lithography to further booster the light efficiency. In this article, the fabrication of ZnO photonic crystals is carried out by nanosphere lithography using inductively coupled plasma reactive ion etching with CH4/H2/Ar plasma on the n-ZnO/p-GaN heterojunction LEDs. The CH4/H2/Ar mixed gas gives high etching rate of n-ZnO film, which yields a better surface morphology and results less plasma-induced damages of the n-ZnO film. Optimal ZnO lattice parameters of 200 nm and air fill factor from 0.35 to 0.65 were obtained from fitting the spectrum of n-ZnO/p-GaN LED using a MATLAB code. In this article, we will show our recent result that a ZnO photonic crystal cylinder has been fabricated using polystyrene nanosphere mask with lattice parameter of 200 nm and radius of hole around 70 nm. Surface morphology of ZnO photonic crystal was examined by scanning electron microscope.

Fabrication of ZnO Nanobrushes by H2–C2H2 Plasma Etching for H2 Sensing Applications

“…Formation of nano-on-micro nanowire arrays via a self-patterning process enhanced by sidewall protection has previously not been reported for plasma etching of ZnO. Previously fabrication of ZnO nanostructures using plasma etching has been performed by using lithography , or particles as masks . Additionally, wet chemical etching of ZnO using different techniques, for example, via oleic acid or acetic acid can increase the surface area of ZnO microstructure , albeit to a much lesser degree.…”

“…Previously fabrication of ZnO nanostructures using plasma etching has been performed by using lithography 18,20 or particles as masks. 19 Additionally, wet chemical etching of ZnO using different techniques, for example, via oleic acid or acetic acid can increase the surface area of ZnO microstructure 54,55 albeit to a much lesser degree. Thus, the process presented in this study allows for both ease of fabrication by eliminating the necessity for a patterning step as well as offering unique increase in surface area via the formation of nanowire arrays.…”

“…Plasma surface treatment of ZnO has been reported to improve optical properties, alter electrical behavior, and enhance sensing properties . Additionally, reactive ion or dry etching plasma processes of ZnO have been used in the fabrication of devices − as well as modification of surface morphology. , …”

Van der Waals Self-Assembled Silica-Nanosphere/Graphene Buffer Layer for High-Quality Gallium Nitride Growth

“…However, the surface hydrophobicity of the sapphire substrate hinders the large-scale preparation of the 2D-ordered nanosphere structure on the sapphire substrate using spin-coating technology . In addition, most reports indicate only small-area 2D-ordered structures on the order of scanning electron microscopy (SEM). − …”

Plasma sputtering depositions with colloidal masks for fabrication of nanostructured surfaces with enhanced photocatalytic activity

“…The discovery of the ability of spherical nanoparticles from a colloidal solution to self assemble on substrate surfaces [1] opened up the opportunity for the construction of nano masks to be used in etching or depositions for the fabrication of 2D nanopatterned surfaces with a relatively large, but limited, choice of motives and shapes. The whole nanofabrication process has been called nanosphere lithography (NSL) [2] and is nowadays intensely investigated for the fabrication of 2D nanopatterned surfaces with applications in cell biology [3], biosensors [4,5], photonic crystals [6,7], optoelectronic devices [8], and surface wetting [9]. Various materials (metals, oxides, polymers, self assembled molecular layers, etc) can be nanopatterned by this technique on a wafer-scale area with relatively low-cost and high throughput.…”