Picture of two heads

Open Access research that challenges the mind...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs. Strathprints provides access to thousands of Open Access research papers by University of Strathclyde researchers, including those from the School of Psychological Sciences & Health - but also papers by researchers based within the Faculties of Science, Engineering, Humanities & Social Sciences, and from the Strathclyde Business School.

Discover more...

GaN micro-light-emitting diode arrays with monolithically integrated sapphire microlenses

Choi, H.W. and Liu, C. and Gu, E. and McConnell, G. and Girkin, J.M. and Watson, I.M. and Dawson, M.D. (2004) GaN micro-light-emitting diode arrays with monolithically integrated sapphire microlenses. Applied Physics Letters, 84 (13). pp. 2253-2255. ISSN 0003-6951

Full text not available in this repository. (Request a copy from the Strathclyde author)


GaN micro-light-emitting diodes (micro-LEDs) with monolithically integrated microlenses have been demonstrated. Microlenses, with a focal length of 44 µm and a root mean square roughness of ~1 nm, have been fabricated on the polished back surface of a sapphire substrate of an array of micro-LEDs by resist thermal reflow and plasma etching. The optical properties of the microlenses have been demonstrated to alter the emission pattern of the LED emitters. The cone of light emitted from this hybrid device is significantly less divergent than a conventional broad-area device. This combination of micro-LED and microlens technologies offers the potential for further improvement in the overall efficiency of GaN-based light emitters.