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Light Emitting Diodes (Leds) for General Illumination

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Light Emitting Diodes (LEDs) for General Illumination AN OIDA TECHNOLOGY ROADMAP UPDATE 2002 Full Edition Including Tutorial Source Material Bridge illuminated by white LEDs in Duisburg, Germany November 2002 Sponsored by: Optoelectronics Industry Development Association (OIDA) National Electrical Manufacturers Association (NEMA) Department of Energy – Office of Building Technology, State and Community Programs Edited by: Jeff Y. Tsao, Sandia National Laboratories Published by: OIDA Member Use Only OIDA Copyright 2002 Optoelectronics Industry Development Association All data contained in this report is proprietary to OIDA and may not be distributed in either original or reproduced form to anyone outside the client’s internal organization without prior written permission of the Optoelectronics Industry development Association. Published by: Optoelectronics Industry Development Association 1133 Connecticut Avenue, NW, Suite 600 Washington, DC 20036 Phone: (202) 785-4426 Fax: (202) 785-4428 Internet: http://www.oida.org Sponsored by: Optoelectronics Industry Development Association (OIDA) National Electrical Manufacturers Association (NEMA) Department of Energy – Office of Building Technology, State and Community Programs (DOE-BTS) Edited by: Jeff Y. Tsao Sandia National Laboratories P.O. Box 5800 Albuquerque, NM 87185-0601 Phone: (505) 844-7092 Fax: (505) 844-3211 E-mail: [email protected] Internet: http://lighting.sandia.gov TABLE OF CONTENTS Preface.................................................................................................................................................. 1 Executive Summary.............................................................................................................................2 R Roadmap Recommendations ..........................................................................................................4 R-1 Lamp Targets .........................................................................................................................................4 R-2 Chip and Phosphor Sub targets.............................................................................................................11 R-3 Challenge Areas.................................................................................................................................... 15 R-4 Decisions .............................................................................................................................................. 17 R-5 Challenges and Possible Approaches................................................................................................... 17 0 Technology Overview .....................................................................................................................24 0.1 History ................................................................................................................................................... 24 0.2 Benefits .................................................................................................................................................. 26 0.3 Birth-Death Life Cycle of Photons ........................................................................................................ 28 0.4 Technology Building Blocks ................................................................................................................. 32 1 Substrates, Buffers and Epitaxy......................................................................................................33 1.1 Substrates ............................................................................................................................................... 35 1.2 Buffers.................................................................................................................................................... 38 1.3 Epitaxy Tools......................................................................................................................................... 43 1.4 Epitaxy Processes .................................................................................................................................. 49 2 Physics, Processing and Devices....................................................................................................55 2.1 Semiconductor Physics.......................................................................................................................... 55 2.2 Device Processing ................................................................................................................................. 62 2.3 LEDs and Integrated LEDs .................................................................................................................. 66 2.4 Directional Emitters .............................................................................................................................. 69 3 Lamps, Luminaires and Systems....................................................................................................76 3.1 Phosphors and Encapsulants................................................................................................................. 76 3.2 Lamps and Electronics.......................................................................................................................... 82 3.3 Luminaires............................................................................................................................................. 87 3.4 Lighting Systems ................................................................................................................................... 90 A Appendix: Roadmapping Process and Resources........................................................................ 94 A-1 Primary References............................................................................................................................... 94 A-2 Workshop Agenda ................................................................................................................................ 96 A-3 Workshop Attendees............................................................................................................................. 97 A-4 Technical Coordinators and Contributors...........................................................................................102 A-5 Bibliography ........................................................................................................................................103 LEDs for General Illumination Update 2002 – Full Edition OIDA Member Use Only Preface PREFACE This volume is an update to the OIDA technology the National Electrical Manufacturing Association roadmap on Light Emitting Diodes (LEDs) for General (NEMA), covered that part. Illumination, issued in March 2001. The original roadmap, We are indebted to Sandia National Laboratories who produced in collaboration with the Department of Energy provided support in collecting the roadmap material and, in (DOE-BTS), responded to a major opportunity to particular, to Jeff Tsao, who assembled and edited the final accelerate the development and commercialization of solid report. Dr. Tsao has done an exceptionally thorough job. state light sources for general illumination. The new light He not only enumerated the decision points and sources offer savings in energy consumption, reduced recommendations for the future R&D activities, but also pollution, substantial savings to the consumers, and the provided a comprehensive tutorial of all the building blocks creation of a new lighting industry. that must be assembled to produce a solid state lighting Both industry and government have responded to this system. As a result, this update containing the enticing challenge. Both Houses of Congress passed an recommendations includes tutorial source material authorization bill, called the Next Generation Lighting describing the various technical areas. Note that Initiative, to generate an industry-government partnership “challenges” and “recommendations” are interchangeable for the acceleration of this technology. It was in in the vocabulary of the report since all recommendations preparation for this national initiative that DOE and OIDA are aimed at meeting the challenges. decided to update the first roadmap. In assembling this comprehensive report, we had the Since the ultimate implementation of solid-state lighting benefit of contributions from all resources in solid-state also requires the development of new lighting fixtures and lighting: industry, academia and national laboratories. We powering, a first look at lighting systems was also included especially acknowledge contributions to the various in this update. The third participant in the roadmap update, chapters of this roadmap from: Chuck Becker Kate Bogart John Bumgarner Chips Chipalkatti Weng Chow Mike Coltrin George Craford Randy Creighton Bob Davis Steve DenBaars Kevin Dowling Dan Doxsee Art Fischer James Gee Jim George Eric Jones Bernd Keller Tom Keuch Dan Koleske Mike Krames Paul Martin Christine Mitchell Sam Myers Shuji Nakamura Nadarajah Narendran Arto Nurmikko Yoshi Ohno Steve Richfield Spilios Riypoulos Lauren Rohwer Michael Scholand Frank Steranka Ed Stokes Yongchoi Tian Roland Haitz Karel Vanheusden Stan Weaver Jerry Simmons Bob Biefeld Arpad Bergh LEDs for General Illumination Update 2002 – Full Edition Page 1 OIDA Member Use Only Executive Summary EXECUTIVE SUMMARY SSL-LEDs and their Benefits SSL-LED Roadmaps Solid-State Lighting through
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