GaN-based light-emitting diodes with photonic crystals structures fabricated by porous anodic alumina template

School of Physics and State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, Peking University, Beijing, China
Optics Express (Impact Factor: 3.53). 09/2011; 19 Suppl 5(19):A1104-8. DOI: 10.1364/OE.19.0A1104
Source: PubMed

ABSTRACT In this paper, we propose and demonstrate a convenient and flexible approach for preparation large-area of photonic crystals (PhCs) structures on the GaN-based LED chip. The highly-ordered porous anodic alumina (AAO) with pitch of wavelength scale was adopted as a selective dry etching mask for PhCs-pattern transfer. The PhCs with different pore depths were simultaneously formed on the entire surfaces of GaN-based LED chip including ITO, GaN surrounding contacts and the sidewall of the mesa by one-step reactive ion etching (RIE). The light output power improvement of PhCs-based GaN LED was achieved as high as 94% compared to that of the conventional GaN-based LED.

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