摘要(英) |
In our study, we modulate far-field patterns of LED by using silicon nitride micro structures. We use gray level structures as sub-micro optical elements array, and analyze the far-field patterns of LED modulated by silicon nitride sub-micro structures. From our analysis,we can concentrate far-field pattern intensity above 0.8 in ±30° or spread far-field pattern intensity uniformly above 0.8 in ±60° of LED.
The purpose of structures is a micron scale, which period is 500 nm and the structures is 200 nm. The structures are etched by Inductively-Coupled-Plasma-Etching System. In our study, the purposed sub-micro silicon nitride gray-level grating can be realized. For the far-field patterns modulation of LED, the sub-micro structures can be integrated in array and fabricated on LED to extend the application of LED optical system. |
參考文獻 |
【1】 T. Fujii , Y. Gao , R. Sharma , E. L. Hu , S. P. DenBaars , and
S. Nakamura “ Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening ” Appl. Phys. Lett., Vol. 84, No. 6 ( 2004 )
【2】 Cathleen Rooman , Maarten Kuijk , Roger Vounckx , Paul Heremans “ Reflective-refractive microlens for efficient lightemitting-
diode-to-fiber coupling” Optical Engineering 44(9) , 095005 ( 2005 )
【3】 H. W. Choi, C. Liu, E. Gu , G. McConnell , J. M. Girkin, I. M. Watson, and M. D. Dawson “ GaN micro-light-emitting diode arrays with monolithically integrated sapphire microlenses ” Appl. Phys. Lett., Vol. 84, No. 13, ( 2004 )
【4】 J. J. Wierer , M. R. Kramesa , J. E. Eplera , N. F. Gardnera , J. R. Wendtb , M. M. Sigalasc , S. R. J. Brueckd , D. Lid , and M. Shagame “III-Nitride LEDs with photonic crystal structures ” SPIE Vol. 5739 ( 2005 )
【5】 M.D.B. Charlton , M.E. Zoorob , T.Lee “ Photonic Quasi-Crystal LEDs : Design, modelling, and optimisation. ” SPIE Vol. 6486 64860R-1
( 2007 )
【6】 Mukul Agrawal , Yiru Sun , Stephen R. Forrest , Peter Peumans “ Enhanced outcoupling from organic light-emitting diodes using aperiodic dielectric mirrors ” Appl. Phys. Lett. 90, 241112 ( 2007 )
【7】 Aurélien David , Tetsuo Fujii , Rajat Sharma , Kelly McGroddy ,Shuji Nakamura , Steven P. DenBaars , Evelyn L. Hu , Claude Weisbuch ,Henri Benisty “ Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution ” Appl. Phys. Lett. 88, 061124 ( 2006 ) |