Shuji Nakamura
Encyclopedia
is a professor at the Materials Department of the College of Engineering
, University of California, Santa Barbara
(UCSB).
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, and 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.
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.
Nakamura has also worked on green and white LEDs, and blue laser diodes
, which are used in Blu-ray Disc
s and HD DVD
s.
UCSB College of Engineering
The College of Engineering is one of the three undergraduate colleges at the University of California, Santa Barbara.As of August 2007, there were 146 faculty, 1,319 undergraduate students, and 674 graduate students...
, University of California, Santa Barbara
University of California, Santa Barbara
The University of California, Santa Barbara, commonly known as UCSB or UC Santa Barbara, is a public research university and one of the 10 general campuses of the University of California system. The main campus is located on a site in Goleta, California, from Santa Barbara and northwest of Los...
(UCSB).
Career
Nakamura graduated from the University of TokushimaUniversity of Tokushima
The is a national university in the city of Tokushima, Japan, with seven graduate schools and five undergraduate faculties. The university was founded in 1949, by merging six separate national educational facilities into one.-Overview:...
in 1977 with a degree in electronic engineering
Electronic engineering
Electronics engineering, also referred to as electronic engineering, is an engineering discipline where non-linear and active electrical components such as electron tubes, and semiconductor devices, especially transistors, diodes and integrated circuits, are utilized to design electronic...
, and obtained a master's degree in the same subject two years later, after which he joined the Nichia Corporation
Nichia Corporation
The is a Japanese chemical engineering and manufacturing company, headquartered in Tokushima, Japan with global subsidiaries, that specializes in the manufacturing and distribution of phosphors, including light-emitting diodes , laser diodes, battery materials, and calcium chloride...
, also based in Tokushima. It was while working for Nichia that Nakamura invented the first high brightness GaN LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....
whose brilliant blue
Blue
Blue is a colour, the perception of which is evoked by light having a spectrum dominated by energy with a wavelength of roughly 440–490 nm. It is considered one of the additive primary colours. On the HSV Colour Wheel, the complement of blue is yellow; that is, a colour corresponding to an equal...
light, when partially converted to yellow by a phosphor coating, is the key to white LED lighting, and which went into production in 1993.
Previously, J.I. Pankove and co-workers at RCA
RCA
RCA Corporation, founded as the Radio Corporation of America, was an American electronics company in existence from 1919 to 1986. The RCA trademark is currently owned by the French conglomerate Technicolor SA through RCA Trademark Management S.A., a company owned by Technicolor...
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
P-type semiconductor
A P-type semiconductor is obtained by carrying out a process of doping: that is, adding a certain type of atoms to the semiconductor in order to increase the number of free charge carriers ....
GaN. Nakamura was somewhat luckier than other workers in that another Japanese group led by Professor Isamu Akasaki
Isamu Akasaki
is a Japanese scientist, best known for inventing p-n junction blue LEDs using gallium nitride as early as 1989.-Blue LEDs:Akasaki was born in Kagoshima Prefecture in 1929, and received a Bachelor of Science degree in 1952 from Kyoto University. He received his PhD degree in Electronics from...
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.
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.
Nakamura has also worked on green and white LEDs, and blue laser diodes
Blue laser
A so-called blue laser is a laser that emits electromagnetic radiation at a wavelength of between 360 and 480 nanometres, which the human eye sees as blue or violet. Diode lasers which emit light at 445 nm are becoming popular as handheld lasers. Light of a shorter wavelength than 400 nm is...
, which are used in Blu-ray Disc
Blu-ray Disc
Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs...
s and HD DVD
HD DVD
HD DVD is a discontinued high-density optical disc format for storing data and high-definition video.Supported principally by Toshiba, HD DVD was envisioned to be the successor to the standard DVD format...
s.
Recognition
- In 2002 he was awarded Benjamin Franklin Medal in Physics from the Franklin InstituteFranklin InstituteThe Franklin Institute is a museum in Philadelphia, Pennsylvania, and one of the oldest centers of science education and development in the United States, dating to 1824. The Institute also houses the Benjamin Franklin National Memorial.-History:On February 5, 1824, Samuel Vaughn Merrick and...
. - In 2006 he was awarded FinlandFinlandFinland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
's Millennium Technology PrizeMillennium Technology PrizeThe Millennium Technology Prize is the largest technology prize in the world. It is awarded once every two years by Technology Academy Finland, an independent fund established by Finnish industry and the Finnish state in partnership. The prize is presented by the President of Finland...
for his continuing efforts to make cheaper and more efficient light sources, - In 2008 he won the Prince of Asturias Award for Technical and Scientific Research.
- In 2008 he was awarded an honourary degree of Doctor of Engineering from Hong Kong University of Science and TechnologyHong Kong University of Science and TechnologyThe Hong Kong University of Science and Technology is a public university located in Hong Kong. Established in 1991 under Hong Kong Law Chapter 1141 , it is one of the nine universities in Hong Kong.Professor Tony F. Chan is the president of HKUST...
. - In 2009 he received the Harvey PrizeHarvey PrizeThe Harvey Prize is awarded by the Technion in Haifa, Israel. It is awarded in different disciplines of Science, Technology, Human Health, and Contributions to Peace in the Middle East. Two awards - each of $75,000 - are given away annually...
from the Technion in Israel.
Further reading
- 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)
- Brilliant by Bob Johnstone http://www.prometheusbooks.com/catalog/book_1882.html
External links
- Professor Nakamura's home page at UCSB
- The Solid State Lighting and Energy Center at UCSB
- Shuji Nakamura Wins $188.7 Million Settlement from Former Employer Nichia for Blue Spectrum Breakthrough Technology
- New York Times article on Nakamura's settlement with Nichia - Nitride semiconductor light-emitting device
- Shuji Nakamura wins the 2006 Millennium Technology Prize
- Nichia's Shuji Nakamura: Dream of the Blue Laser Diode
- 2008 Prince of Asturias Award For Technical and Scientific Research
- Harvey Prize