Shuji Nakamura

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Shuji Nakamura
Born (1954-05-22) 22 May 1954 (age 59)
Ikata, Ehime, Japan
Residence United States
Institutions University of California, Santa Barbara
Known for Blue and white LEDs

Shuji Nakamura (中村 修二 Nakamura Shūji?, born May 22, 1954 in Ikata, Ehime, Japan) is a professor at the Materials Department of the College of Engineering, University of California, Santa Barbara (UCSB).,[1] and is regarded as the inventor of the blue LED, a major breakthrough in lighting technology.

Career[edit]

Nakamura graduated from the University of Tokushima in 1977 with a degree in electronic engineering, and obtained a master's degree in the same subject two years later, after which he joined the Nichia Corporation, also based in Tokushima. It was while working for Nichia that Nakamura invented the first high brightness GaN LED whose brilliant blue light, when partially converted to yellow by a phosphor coating, is the key to white LED lighting, which went into production in 1993.

Previously, J.I. Pankove and co-workers at RCA put in considerable effort, but did not manage to make a marketable GaN LED in the 1960s. The principal problem was the difficulty of making strongly p-type GaN. Nakamura was somewhat luckier than other workers in that another Japanese group led by Professor Isamu Akasaki published their method to make strongly p-type GaN by electron-beam irradiation of magnesium-doped GaN. However, this method was not suitable for mass production and its physics was not well understood. Nakamura managed to develop a thermal annealing method which was much more suitable for mass production. In addition, he and his co-workers worked out the physics and pointed out the culprit was hydrogen, which passivated acceptors in GaN.

At the time, many considered creating a GaN LED too difficult to produce, therefore Nakamura was fortunate that the founder of Nichia, Nobuo Ogawa (1912–2002) was initially willing to support his GaN project. However the company eventually ordered him to suspend work on GaN, claiming it was consuming too much time and money. Nakamura continued to develop the blue LED on his own and in 1993 succeeded in making the device.[2]

He was awarded a Doctor of Engineering degree from the University of Tokushima in 1994. He left Nichia Corporation in 1999 and took a position as a professor of engineering at the University of California, Santa Barbara.

In 2001, Nakamura sued his former employer Nichia over his bonus for the discovery, which was originally ¥20,000 (~US$180). Although Nakamura originally won an appeal for ¥20 billion (~US$180 million), Nichia appealed the award and the parties settled in 2005 for ¥840 million (~US$9 million), at the time the largest bonus ever paid by a Japanese company.[citation needed]

Nakamura has also worked on green LEDs, and is responsible for creating the white LED and blue laser diodes, which are used in Blu-ray Discs and HD DVDs.[3]

Nakamura is currently a professor of Materials at the University of California, Santa Barbara, and holds over 100 patents.[4] In 2008, Nakamura, along with fellow UCSB professors Dr. Steven DenBaars and Dr. James Speck, founded Soraa, a leading[citation needed] developer of solid-state lighting technology built on pure gallium nitride substrates.[5]

Recognition[edit]

References[edit]

  1. ^ "Shuji Nakamura". University of California, Santa Barbara. Retrieved 2008-07-31. 
  2. ^ "Court dismisses inventor's patent claim but will consider reward"
  3. ^ "Work in Colored Lights Nets Millennium Prize" by Richard Harris. All Things Considered, June 15, 2006.
  4. ^ "Shuji Nakamura". Solid State Lighting & Energy Center. Retrieved 2012-10-19. 
  5. ^ "About". Soraa Inc. Retrieved 2012-10-19. 
  6. ^ Shuji Nakamura wins the 2006 Millennium Technology Prize [1]
  7. ^ "Top prize for 'light' inventor". BBC News. 2006-09-08. Retrieved 2006-09-08. 
  8. ^ Prince of Asturias Awards for Technical and Scientific Research.
  9. ^ Harvey Prize
  10. ^ "SVIPLA Presents Inventor of the Year - Shuji Nakamura, Ph.D.". Silicon Valley Intellectual Property Law Association. Retrieved 5 March 2013. 

Further reading[edit]

  • Shuji Nakamura, Gerhard Fasol, Stephen J. Pearton, The Blue Laser Diode : The Complete Story, Springer; 2nd edition, October 2, 2000, (ISBN 3-540-66505-6)
  • Bob Johnstone Brilliant!: Shuji Nakamura and the revolution in lighting technology, Prometheus Books, 2007 ISBN 1-59102-462-5

External links[edit]

Preceded by
Tim Berners-Lee
Millennium Technology Prize winner
2006 (for blue and white LEDs)
Succeeded by
Robert S. Langer