| Millennium Technology Prize laureate | |
| Shuji Nakamura | |
| Millennium Technology Prize | |
| Year awarded: | 2006 |
|---|---|
| Invention: | Blue and white LEDs |
| Prize presented by: | Tarja Halonen |
| Previous laureate: | Tim Berners-Lee |
| Following laureate: | Will be announced in 2008 |
Shuji Nakamura (中村 修二 Nakamura Shūji, born in May 22 1954, Ikata, Ehime, Japan) is a professor at the University of California, Santa Barbara (UCSB).
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 is (when partially converted to yellow by a phosphor coating) the key to white LED lighting, and which went into production in 1993.
Previously, J.I. Pankove (RCA) and co-workers put in a lot of effort, but did not manage to make a marketable GaN LED in the 1960's. The principal problem was the difficulty to make 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 Mg-doped GaN. However, this method is not suitable for mass production and its physics were not understood. Nakamura managed to develop a thermal annealing method which is 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.
Nakamura was fortunate that Nobuo Ogawa (1912-2002), the founder of Nichia, was willing to support his GaN project. At that time, GaN LED was considered too difficult by a lot of people in the world.
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 Yen (~US$180). Although Nakamura originally won an appeal for 20 billion Yen (~US$180 million), Nichia appealed the award and the parties settled in 2005 for 840 million Yen (~US$7 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 Discs and HD DVDs.
In 2006, Nakamura was awarded Finland's Millennium Technology Prize for his continuing efforts to make cheaper and more efficient light sources.
