Nakamura graduated from theUniversity of Tokushima in 1977 with aB.Eng. degree inelectronic engineering, and obtained anM.Eng. degree in the same subject two years later, after which he joined theNichia Corporation, also based inTokushima. It was while working for Nichia that Nakamura invented the method for producing the first commercial high brightnessgallium nitride (GaN) LED whose brilliantblue 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 atRCA put in considerable effort but did not make a marketable GaN LED in the 1960s. The principal problem was the difficulty of making stronglyp-type GaN.[6] Nakamura drew on the work of another Japanese group led by ProfessorIsamu Akasaki, who 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. Nakamura developed a thermal annealing method much more suitable for mass production.[7] In addition, he and his co-workers worked out the physics and pointed out the culprit was hydrogen, which passivated acceptors in GaN.[8]
At the time, many considered creating a GaN LED too difficult to produce; therefore, Nakamura was fortunate that the founder of Nichia,Nobuo Ogawa [ja] (1912–2002), was willing to support and fund his GaN project.[9][10] However, the senior Ogawa ceded the presidency to his son-in-law Eiji Ogawa (in 1989). The company under Eiji's direction ordered him to suspend work on GaN, claiming it was consuming too much time and money.[11][12] Nakamura continued to develop the blue LED on his own and in 1993 succeeded in making the device.[13][12]
Despite these circumstances, once Nakamura succeeded in creating a commercially viable prototype, 3 orders of magnitude (1000 times) brighter than previously successful blue LEDs, Nichia pursued developing the marketable product.[9][14] The company's gross receipt surged from just over ¥20 billion (≈US$200 million) in 1993 to ¥80 billion (≈US$800 million) by 2001, 60 percent of which was accounted for by sales of blue LED products.[12] The company's workforce doubled between 1994 and 1999 from 640 to 1300 employees.[15]
Nakamura left Nichia Corporation in 1999 to join the faculty at theUniversity of California, Santa Barbara at the personal invitation of the university's chancellor,Henry T. Yang. Yang flew three times from California to Japan to recruit Nakamura, with promises to build new research facilities and having a Japanese-speaking research staff team already assembled for him.[17][18]
In 2001, Nakamura sued his former employer Nichia over his bonus for the discovery as a part of a series of lawsuits between Nichia and Nakamura with Nichia's US competitorCree Inc.; they agreed in 2000 to jointly sue Nichia at the expense of Cree and Nakamura received stock options from Cree. Nakamura claimed that he received only¥20,000 (≈US$180) for his discovery of "404 patent," though Nichia's president Eiji Ogawa's side of the story was that he was shocked beyond belief that the court would award Nakamura ¥20 billion, and downplaying the significance of the "404 patent," opined that the company had adequately compensated him for the innovation through promotions and bonuses amounting to ¥62 million over 11 years and annual salary which was raised to ¥20 million by the time Nakamura quit Nichia.[19]
Nakamura sued for ¥2 billion (<US$20 million) as his fair share for the invention, and the district court awarded him ten times the amount, ¥20 billion (<US$200 million). However, Nichia appealed the award and the parties settled in 2005 for ¥840 million (≈US$8.1 million, less than 5% of the award amount), which was still the largest payment ever paid by a Japanese company to an employee for an invention,[20][21] an amount only enough to cover legal expenses incurred by Nakamura.[22] In line with the lawsuit, Nakamura has repeatedly criticized Japanese companies for not giving their researchers the salaries and recognition they deserve.[23]
Nakamura is a professor of Materials at the UCSB.[25] In 2008, Nakamura, along with fellow UCSB professors Dr.Steven P. DenBaars and Dr. James Speck, founded Soraa, a developer of solid-state lighting technology built on pure gallium nitride substrates.[26] Nakamura holds 208 US utility patents as of 5 May 2020.[27]
In November 2022, Nakamura co-founded Blue Laser Fusion, acommercial fusion company, with Hiroaki Ohta, a former president of Tokyo-based drone maker ACSL.[28] In July 2023, Blue Laser Fusion raised $25 million from venture capital firmJAFCO Group and the Mirai Creation Fund, which is backed byToyota Motor and other investors and managed by theSPARX Group.[28]
^特許は会社のもの「猛反対」 ノーベル賞の中村修二さん [Patent belongs to the company "Violent opposition" Nobel prize winner Shuji Nakamura] (in Japanese). Asahi Shimbun Digital. 18 October 2014. Archived fromthe original on 25 December 2018. Retrieved22 October 2014.
Shuji Nakamura, Gerhard Fasol, Stephen J. Pearton,The Blue Laser Diode : The Complete Story, Springer; 2nd edition, October 2, 2000, (ISBN3-540-66505-6)
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