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Shuji Nakamura

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Shuji Nakamura is a Japanese-American electronics engineer. He is a specialist in semiconductor technology. This field studies materials that can control the flow of electricity. Nakamura is most famous for co-inventing the blue light-emitting diode, or blue LED. This invention was a major breakthrough for lighting technology. It allowed scientists to create bright, energy-efficient white light. For this work, Nakamura shared the Nobel Prize in Physics in 2014 with Isamu Akasaki and Hiroshi Amano.

Creating a blue LED required using a material called gallium nitride, or GaN. In the 1960s, researchers at RCA tried to use GaN but could not make a marketable light. The main problem was the difficulty of making strongly p-type GaN. In a p-type material, certain electrical properties allow current to flow in a specific way. Professor Isamu Akasaki found a method using electron-beam irradiation of magnesium-doped GaN. However, this method was not suitable for mass production. Nakamura developed a different method called thermal annealing. This process uses heat to treat the material. This made the process much better for making many lights at once.

Nakamura and his team also discovered why the material was difficult to work with. They found that hydrogen was the culprit. The hydrogen passivated acceptors in the GaN, which stopped the material from working correctly. By solving this, Nakamura created a prototype that was much more powerful. His blue LED was 3 orders of magnitude, or 1,000 times, brighter than previous versions. This high brightness is essential for modern uses. When this blue light passes through a yellow phosphor coating, it converts to white light. This is how most white LED lighting works today.

Nakamura began his career in Japan. He graduated from the University of Tokushima in 1977. He earned his master's degree in electronic engineering in 1979. After graduation, he joined the Nichia Corporation in Tokushima. At the time, many thought making a GaN LED was too difficult. Nakamura was fortunate that the founder of Nichia supported his project. However, the company's direction changed in 1989. The new president, Eiji Ogawa, ordered Nakamura to stop his work. He claimed the project used too much time and money. Nakamura continued his research on his own. He finally succeeded in 1993.

Nakamura's success changed the business of Nichia Corporation. The company's gross receipts grew significantly. In 1993, receipts were just over ¥20 billion, which was about US$200 million. By 2001, they reached ¥80 billion, or about US$800 million. Blue LED products accounted for 60 percent of these sales. The company's workforce also grew quickly. It doubled from 640 employees in 1994 to 1,300 employees in 1999. In 1994, the University of Tokushima awarded Nakamura a D.Eng. degree for his research.

In 1999, Nakamura moved to the United States. He joined the University of California, Santa Barbara (UCSB). The university's chancellor, Henry T. Yang, personally invited him. Yang traveled from California to Japan three times to recruit him. He promised new research facilities and a Japanese-speaking staff. Nakamura's move was followed by a legal dispute with Nichia. He sued for his fair share of the profits from his discovery. He originally sued for ¥2 billion, which is less than US$20 million. A district court awarded him ten times that amount, or ¥20 billion. After an appeal, the parties settled in 2005 for ¥840 million. This was about US$8.1 million. This settlement was the largest ever paid by a Japanese company to an employee for an invention.

Nakamura has continued to innovate throughout his career. He worked on green LEDs and blue laser diodes. These lasers are used in Blu-ray Discs and HD DVDs. At UCSB, he is a Professor of Materials and Electrical and Computer Engineering. In 2008, he co-founded Soraa to develop lighting technology. He also co-founded Blue Laser Fusion in 2022. This company focuses on commercial fusion. As of May 2020, Nakamura holds 208 US utility patents. His work connects the science of materials to the technology we use every day.

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