EXPERIENCE - EPFL
1996 - 2000PhD student and research engineer
1996 – 2000 (4 yrs) | Lausanne and Zürich, Switzerland
Ecole Polytechnique Fédérale de Lausanne (EPFL)
Institut de Micro-Optoélectronique (IMO)
Département de Physique
Thesis advisor : Pr. Marc Ilegems
My responsabilities:
- As Research Engineer and Teaching Assistant, I have done a PhD thesis in physics on the design, fabrication and characterization of red (650nm) high brightness resonant cavity light emitting diodes (RCLEDs), also known as micro cavity light emitting diodes (MCLEDs). This type of device has the same structure as a VCSEL (Vertical cavity surface emitting laser), but it is designed in such a way that stimulated emission is suppressed and spontaneous emission is maximized.
- The theoretical work was done at EPFL (Swiss Federal Institute of Technology) and the practical work in Zurich in the laboratories of the Paul Scherrer Institute – Zürich (formerly RCA Laboratories), which was then transferred in 1997 to the Swiss Center for Electronics and Microtechnology (CSEM) and renamed as CSEM-Z.
Main achievements:
- Established new analytical models to optimize the brightness of a new generation of LEDs
- Validation of the models by comparison with devices which I processed in clean-room and then characterized (electro-optical measurements)
- This work allowed world record of efficiency for red MCLEDs manufactured by the company Mitel Semiconductors
- Several papers published in international journals and presented in international conferences
- PhD thesis (link to the pdf)
Publications:
[1] J. F. Carlin, P. Royo, M. Ilegems, B. Gerard, X. Marcadet, J. Nagle, “High-efficiency top-emitting microcavity LEDs on GaAs and GaAs/Si substrates”, Journal of Crystal Growth, 201/202 (1999) pp. 994-998
[2] P. Royo, R. P. Stanley, R. Houdré, M. Ilegems, M. Moser, R. Hövel, H. P. Schweizer, K. H. Gulden, “AlGaInP-based microcavity light emitting diodes: controlled on-wafer detuning and measurement of the internal quantum efficiency”, Applied Physics Letters, 75 (1999) pp. 4052-4054
[3] J. F. Carlin, P. Royo, R. P. Stanley, R. Houdré, J. Spicher, U. Oesterle and M. Ilegems, “Design and characterization of top-emitting microcavity light emitting diodes”, Semiconductor Science and Technology, 15 (2000) pp. 145-154
[4] P. Royo, R. P. Stanley, M. Ilegems, K. Streubel, K. H. Gulden, “Deconvolution of the intrinsic spontaneous spectrum of vertical cavity surface emitting devices”, Applied Physics Letters, 77 (2000) pp. 3899-3901
[5] P. Royo, R. P. Stanley, M. Ilegems, K. H. Gulden, K. Streubel, “On-wafer determination of the intrinsic spontaneous spectrum of vertical cavity surface emitting devices”, Electronics Letters, 36 (2000) pp. 2106-2108
[6] P. Royo, R. P. Stanley, M. Ilegems, “Coupling of impurity modes in one-dimensional periodic systems”, Physical Review E, 64, 1 (2001) pp. 016604-1 to 016604-6
[7] P. Royo, R. P. Stanley, M. Ilegems, “Planar dielectric microcavity light-emitting diodes: analytical analysis of the extraction efficiency”, Journal of Applied Physics, 90, 1 (2001) pp. 283-293
[8] P. Royo, R. P. Stanley, M. Ilegems, K. Streubel, K. H. Gulden, “Experimental determination of the internal quantum efficiency of AlGaInP-based Microcavity Light-Emitting Diodes”, Journal of Applied Physics, 91, 5 (2002) pp. 2563-2568
[9] P. Royo, R. P. Stanley, M. Ilegems, “Analytical Calculation of the Extraction Efficiency of Microcavity Light-Emitting Diodes for Display and Fiber Coupling Applications”, IEEE- Journal of Selected Topics in Quantum Electronics, Vol. 8, No. 2, (2002), pp. 207-218
Conferences:
[1] P. Royo, R. Stanley, R. Houdré, M. Ilegems, E. Greger, H. P. Schweizer, M. Moser, K. H. Gulden, “Visible microcavity light-emitting diodes”, Quantum Electrodynamics Phenomena and Applications of Microcavities and Photonics Crystals, Institut d’Etudes Scientifiques de Cargèse, Corse, France, August 3rd-15th (1998)
[2] P. Royo, R. Stanley, R. Houdré M. Ilegems, E. Greger, H. P. Schweizer, M. Moser, K. H. Gulden, “Visible microcavity light-emitting diodes”, Summer School and European Optical Society Topical Meeting on Semiconductor Microcavity Light Emitters, Centro Stefano Franscini, Monte Verita, Ascona, Switzerland, September 20th-25th (1998)
[3] P. Royo, J. F. Carlin, J. Spicher, R. Stanley, R. Houdré, V. Bardinal, U. Oesterle, M. Ilegems, “High efficiency top-emitting microcavity light-emitting diodes”, SPIE Conference on Light-Emitting Diodes: Research, Manufacturing and Applications III, San José, California, USA, SPIE Vol. 3621 (1999) pp. 151-157
[4] P. Royo, M. Ilegems , M. Moser, R. Hövel, H. P. Schweizer, K. H. Gulden, “Controlled growth variation for the detuning of AlGaInP-based microcavity light emitting diodes”, Proceedings of the Indium Phosphide and Related Materials Conference IPRM’99 in Davos, Switzerland, ISBN 0-7803-5562-8 (1999) pp. 111-117
[5] P. Royo, R. P. Stanley, M. Ilegems, K. H. Gulden, K. Streubel,”Deconvolution of the intrinsic spectrum of AlGaInP microcavity light-emitting diodes” Proceedings of the 27th International Symposium on Compound Semiconductors ISCS’00 in Monterey, California, USA, pp. 425 -429 (2000)
[6] P. Royo, R. P. Stanley, M. Ilegems, K. H. Gulden, K. Streubel, “Factors determining the external quantum efficiency of AlGaInP Microcavity Light-Emitting Diodes” Proceedings of the 27th International Symposium on Compound Semiconductors ISCS’00 in Monterey, California, USA, pp. 431 -435 (2000)
[7] P. Royo, R. Stanley, M. Ilegems, K. Streubel, K. H. Gulden, “Study of the external quantum efficiency of red MCLEDs”, European Optical Society Topical Meeting and Summer School on semiconductor microcavity photonics, Centro Stefano Franscini, Monte Verita, Ascona, Switzerland, October 21th-25th (2000)
[8] P. Royo, R. P. Stanley, M. Ilegems, K. Streubel, M. Moser, K. H. Gulden, “Study of the internal quantum efficiency of AlGaInP Microcavity Light-Emitting Diodes”, SPIE Conference on Light-Emitting Diodes: Research, Manufacturing and Applications III, San José, California, USA SPIE Vol. 4278 (2001)