In this paper we investigate the utilization of a patterned photonic crystal layer positioned below the Multiple Quantum Well region of a p-side up LED to improve light extraction and investigate the benefit of adding additional top surface photonic crystal patterning to the same device. Performance for each design is evaluated in terms of angular extraction efficiency and far field angular beam profile for fixed lattice geometry and a range of etch depths. We show that a buried photonic crystal lattice improves extraction for emission angles below the critical angle for total internal reflection, and does not have a detrimental effect over the normal extraction cone of the LED. An improvement of (33% to 57% in extraction efficiency is obtained using a buried photonic crystal lattice alone. The introduction of additional top surface patterning has potential to further improve the extraction efficiency up to 73%, and to tailor the shape of the emission profile.
|Number of pages||8|
|Journal||Proceedings of SPIE - The International Society for Optical Engineering|
|Publication status||Published - 18 Aug 2010|
|Event||10th International Conference on Solid State Lighting, August 2, 2010 - August 4, 2010 - San Diego, CA, USA United States|
Duration: 1 Aug 2010 → …