Fabrication and characterization of freestanding circular GaN gratings

Yongjin Wang, Fangren Hu, Hidehisa Sameshima, Kazuhiro Hane

Research output: Contribution to journalArticlepeer-review

18 Citations (Scopus)


It's of significant interest to combine freestanding nanostructure with active gallium nitride (GaN) material for surface-emitting optoelectronic application. By utilizing bulk micromachining of silicon, we demonstrate here a promising way to fabricate freestanding GaN nanostructures using a GaN-on-silicon system. The well-defined nanoscale circular GaN gratings are realized by fast-atom beam (FAB) etching, and the freestanding GaN gratings are obtained by removing silicon substrate using deep reactive ion etching (DRIE). The freestanding GaN slab is thinned from the backside by FAB etching to reduce the confined modes inside the GaN slab. The measured microphotoluminescence (micro-PL) spectra experimentally demonstrate significant enhancements in peak intensity and integrated intensity by introducing freestanding circular grating. This work represents an important step in combining GaN-based active material with freestanding nanostructures for further increasing light-extraction efficiency.

Original languageEnglish
Pages (from-to)773-779
Number of pages7
JournalOptics Express
Issue number2
Publication statusPublished - 2010 Jan 18


Dive into the research topics of 'Fabrication and characterization of freestanding circular GaN gratings'. Together they form a unique fingerprint.

Cite this