Isamu Akasaki

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Isamu Akasaki
赤﨑 勇
Akasaki in 2011
Born(1929-01-30)January 30, 1929
Chiran, Kagoshima Prefecture, Empire of Japan
DiedApril 1, 2021(2021-04-01) (aged 92)
Nagoya, Aichi Prefecture, Japan
Alma mater
Known forBlue and white LEDs
SpouseRyoko Akasaki
Awards
Scientific career
FieldsOptoelectronics
Institutions
ThesisGeの気相成長に関する研究 (1964)
Doctoral studentsHiroshi Amano
Category:Articles with hCards

Isamu Akasaki (Japanese: 赤﨑 勇, romanized: Akasaki IsamuCategory:Articles containing Japanese-language text; January 30, 1929 – April 1, 2021) was a Japanese electronics engineer specializing in the field of semiconductor technology. He is best known for co-inventing the bright gallium nitride (GaN) p–n junction blue LED in 1989 and subsequently the high-brightness GaN blue LED as well.[1][2][3][4][5]

Akasaki was awarded the 2014 Nobel Prize in Physics, along with Hiroshi Amano and Shuji Nakamura, "for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources."[6]

Early life and education

Isamu Akasaki was born on January 30, 1929, in Chiran, Japan, and was raised in Kagoshima.[7][8] His elder brother is Masanori Akazaki [ja], who was an electronic engineering researcher and a Professor Emeritus at Kyushu University.[8] (Their surname "赤﨑Category:Articles containing Japanese-language textCategory:Articles containing Japanese-language text" is also pronounced Akazaki.[9][10])

Akasaki graduated from Kagoshima Prefectural Daini-Kagoshima Middle School (now Kagoshima Prefectural Konan High School) in 1946, from Seventh Higher School Zoshikan (now Kagoshima University) in 1949[8] and from Department of Chemistry, Faculty of Science, Kyoto University in 1952.[7] During his university years, he visited shrines and temples that local residents rarely visit, walked around the mountains of Shinshu during the summer vacation, enjoyed classes and enjoyed a fulfilling student era.[7] After he became a researcher, he obtained the degree of Doctor of Engineering from Nagoya University in 1964.[11]

Career

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From 1952 to 1959, Akasaki worked as a research scientist at Kobe Kogyo Corporation (now, Fujitsu Ltd.).[12] From 1959 to 1964, he was Research Associate, Assistant Professor, and Associate Professor in the Department of Electronics at Nagoya University. He was head of the Basic Research Laboratory at Matsushita Research Institute Tokyo, Inc. from 1964 until 1974, when he became general manager of the Semiconductor Department (in the same institute until 1981).Category:All articles with unsourced statementsCategory:Articles with unsourced statements from April 2021[citation needed] In 1981 he became a professor in the Department of Electronics at Nagoya University until 1992.[12]

From 1987 to 1990, Akasaki was a project leader of "Research and Development of GaN-based Blue Light–Emitting Diode" sponsored by Japan Science and Technology Agency (JST). He then led the "Research and Development of GaN-based Short-Wavelength Semiconductor Laser Diode" product sponsored by JST from 1993 to 1999. While he led this project, he was also a visiting professor at the Research Center for Interface Quantum Electronics at Hokkaido University, from 1995 to 1996. In 1996 he was a project leader of the Japan Society for the Promotion of Science's for the "Future program" up to 2001. From 1996 he started as a Project Leader of "High-Tech Research Center for Nitride Semiconductors" at Meijo University, sponsored by MEXT until 2004. From 2003 up to 2006 he was the chairman of "R&D Strategic Committee on the Wireless Devices Based on Nitride Semiconductors" sponsored by METI.

In 1992, Akasaki left Nagoya University to join the faculty of Meijo University.[12] He was the director of the Research Center for Nitride Semiconductors at Meijo University from 2004. He also worked as a Research Fellow at Akasaki Research Center of Nagoya University from 2001.

Research

Akasaki started working on GaN-based blue LEDs in the late 1960s. Step by step, he improved the quality of GaN crystals and device structures[13] at Matsushita Research Institute Tokyo, Inc. (MRIT), where he decided to adopt metalorganic vapor phase epitaxy (MOVPE) as the preferred growth method for GaN.

In 1981, Akasaki started afresh the growth of GaN by MOVPE at Nagoya University, and in 1985 he and his group succeeded in growing high-quality GaN on sapphire substrate by pioneering the low-temperature (LT) buffer layer technology.[14][15]

This high-quality GaN enabled them to discover p-type GaN by doping with magnesium (Mg) and subsequent activation by electron irradiation (1989), to produce the first GaN p-n junction blue/UV LED (1989), and to achieve conductivity control of n-type GaN (1990)[16] and related alloys (1991)[17] by doping with silicon (Si), enabling the use of hetero structures and multiple quantum wells in the design and structure of more efficient p-n junction light emitting structures.

They achieved stimulated emission from the GaN firstly at room temperature in 1990,[18] and developed in 1995 the stimulated emission at 388 nm with pulsed current injection from high-quality AlGaN/GaN/GaInN quantum well device.[19] They verified quantum size effect (1991)[20] and quantum confined Stark effect (1997)[21] in nitride system, and in 2000 showed theoretically the orientation dependence of piezoelectric field and the existence of non-/semi-polar GaN crystals,[22] which have triggered today's worldwide efforts to grow those crystals for application to more efficient light emitters.

Nagoya University Akasaki Institute

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Akasaki Institute, Nagoya University

Akasaki's patents were produced from these inventions, and the patents have been rewarded as royalties. Nagoya University Akasaki Institute[23] opened on October 20, 2006. The cost of construction of the institute was covered with the patent royalty income to the university, which was also used for a wide range of activities in Nagoya University. The institute consists of an LED gallery to display the history of blue LED research/developments and applications, an office for research collaboration, laboratories for innovative research, and Akasaki's office on the top sixth floor. The institute is situated in the center of the collaboration research zone in Nagoya University Higashiyama campus.

Personal life

He and his wife Ryoko lived in Nagoya, and the couple had no children.

Death

Akasaki died from pneumonia at a hospital in Nagoya on April 1, 2021, at the age of 92.[24]

Recognition

Awards

Year Organization Award Citation Ref.
1998 United States IEEE IEEE Jack A. Morton Award[a] "For contributions in the field of group-III nitride materials and devices." [25]
1998 United Kingdom Rank Foundation Rank Prize for Optoelectronics[b] "For contributions to the invention of nitride based blue and green semiconductor diode lasers." [26]
1998 Japan NEC C&C Foundation C&C Prize[a] "For basic and pioneering contributions to the development of high brightness and long lifetime blue light-emitting devices using nitride-based compound semiconductors." [27]
1999 United States Electrochemical Society Gordon E. Moore Medal for Outstanding Achievement in Solid State Science and Technology [28]
2000 Japan The Asahi Shimbun Asahi Prize[a] "For their research and development of a blue light emitting device." [29]
2006 United States The Minerals, Metals & Materials Society John Bardeen Award "For his pioneering work and key discoveries in the field of GaN and related materials which has enabled their widespread development and use." [30]
2009 Japan Inamori Foundation Kyoto Prize in Advanced Technology "Pioneering Work on Gallium Nitride p-n Junctions and Related Contributions to the Development of Blue Light Emitting Devices." [31]
2011 United States IEEE IEEE Edison Medal "For seminal and pioneering contributions to the development of nitride-based semiconductor materials and optoelectronic devices, including visible wave length LEDs and lasers." [32]
2013 United States Society for Information Display Karl Ferdinand Braun Prize [33]
2014 Sweden Royal Swedish Academy of Sciences Nobel Prize in Physics[b] "For the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources." [6]
2015 United States National Academy of Engineering Charles Stark Draper Prize[c] "For the invention, development, and commercialization of materials and processes for light-emitting diodes (LEDs)." [34]
2015 United States Asia Society Asia Game Changer Award[b] "For lighting our world in a groundbreaking and sustainable way." [35]
2016 Singapore Asian Scientist Asian Scientist 100 [36]
2021 United Kingdom Queen Elizabeth Prize for Engineering Foundation Queen Elizabeth Prize for Engineering[c] "For the creation and development of LED lighting, which forms the basis of all solid state lighting technology." [37]

Memberships

Year Organization Type Ref.
1999 United States IEEE Fellow [38]
2008 United States National Academy of Engineering International Member [39]

Orders

Year Head of state Order Ref.
2011 Japan Akihito Order of Culture [40]

See also

Notes

  1. 1 2 3 Awarded jointly with Shuji Nakamura.
  2. 1 2 3 Awarded jointly with Hiroshi Amano and Shuji Nakamura.
  3. 1 2 Awarded jointly with M. George Craford, Russell Dupuis, Nick Holonyak, and Shuji Nakamura.

References

  1. ↑ Isamu Akasaki; Hiroshi Amano (2006). "Breakthroughs in Improving Crystal Quality of GaN and Invention of the p–n Junction Blue-Light-Emitting Diode". Japanese Journal of Applied Physics. 45 (12): 9001–9010. Bibcode:2006JaJAP..45.9001A. doi:10.1143/JJAP.45.9001. S2CID 7702696. Archived from the original on July 22, 2012. Retrieved November 10, 2015.
  2. ↑ "Japanese Journal of Applied Physics". jsap.jp. Archived from the original on April 18, 2012. Retrieved November 10, 2015.
  3. ↑ Amano, Hiroshi; Kito, Masahiro; Hiramatsu, Kazumasa; Akasaki, Isamu (December 20, 1989). "P-Type Conduction in Mg-Doped GaN Treated with Low-Energy Electron Beam Irradiation (LEEBI)". Japanese Journal of Applied Physics. 28 (Part 2, No. 12). Japan Society of Applied Physics: L2112–L2114. Bibcode:1989JaJAP..28L2112A. doi:10.1143/jjap.28.l2112. ISSN 0021-4922.
  4. ↑ Isamu Akasaki; Hiroshi Amano; Masahiro Kito; Kazumasa Hiramatsu (1991). "Photoluminescence of Mg-doped p-type GaN and electroluminescence of GaN p-n junction LED". Journal of Luminescence. 48–49. Elsevier BV: 666–670. Bibcode:1991JLum...48..666A. doi:10.1016/0022-2313(91)90215-h. ISSN 0022-2313.Category:CS1: long volume value
  5. ↑ Isamu Akasaki, Hiroshi Amano, Kenji Itoh, Norikatsu Koide and Katsuhide Manabe: "GaN-based UV/blue light emitting devices", Inst. Phys. Conf. Ser. No.129, pp. 851-856, 1992
  6. 1 2 "Nobel Prize in Physics 2014". Nobel Foundation. Archived from the original on April 7, 2024. Retrieved October 7, 2014.
  7. 1 2 3 "ノーベル物理学賞受賞者・赤﨑勇博士と京都大学 －大学時代に育まれた研究者の芽－" (in Japanese). Kyoto University. Retrieved September 5, 2021.Category:CS1 Japanese-language sources (ja)
  8. 1 2 3 赤﨑勇(AKASAKI Isamu)"青い光に魅せられて 青色LED開発物語", Japan:日本経済新聞出版社(Nikkei Business Publications),2013
  9. ↑ "Asia University Summit pp.7-8" (PDF). Aichi Prefectural Government. 2021. Archived from the original (PDF) on July 9, 2022. Retrieved June 27, 2022.
  10. ↑ Juichi Yamagiwa (July 16, 2015). "Welcome Speech by Juichi Yamagiwa, Dr. of Science, President of Kyoto University - UNESCO International Scientific Symposium Kyoto University, 16 July, 2015" (PDF). Kyoto University OCW (Open Course Ware). Kyoto University. p. 2. Retrieved June 27, 2022.
  11. ↑ 赤崎, 勇 (1964). Geの気相成長に関する研究 (DEng) (in Japanese). National Institute of Informatics. Retrieved June 27, 2022.Category:CS1 uses Japanese-language script (ja)Category:CS1 Japanese-language sources (ja)
  12. 1 2 3 "Akasaki Isamu". Encyclopedia Britannica. Retrieved April 7, 2021.
  13. ↑ Y. Ohki, Y. Toyoda, H. Kobayasi and I. Akasaki: "Fabrication and properties of a practical blue-emitting GaN m-i-s diode. Inst. Phys. Conf. Ser. No. 63, pp. 479-484 (Proc. of the 9th Intl. Symposium on Gallium Arsenide and Related Compounds, 1981).
  14. ↑ Amano, H.; Sawaki, N.; Akasaki, I.; Toyoda, Y. (February 3, 1986). "Metalorganic vapor phase epitaxial growth of a high quality GaN film using an AlN buffer layer". Applied Physics Letters. 48 (5). AIP Publishing: 353–355. Bibcode:1986ApPhL..48..353A. doi:10.1063/1.96549. ISSN 0003-6951.
  15. ↑ Akasaki, Isamu; Amano, Hiroshi; Koide, Yasuo; Hiramatsu, Kazumasa; Sawaki, Nobuhiko (1989). "Effects of ain buffer layer on crystallographic structure and on electrical and optical properties of GaN and Ga1−xAlxN (0 < x ≦ 0.4) films grown on sapphire substrate by MOVPE". Journal of Crystal Growth. 98 (1–2). Elsevier BV: 209–219. doi:10.1016/0022-0248(89)90200-5. ISSN 0022-0248.
  16. ↑ H. Amano and I. Akasaki: "Fabrication and Properties of GaN p-n Junction LED", Mater. Res. Soc. Extended Abstract (EA-21), pp.165-168, 1990, (Fall Meeting 1989)
  17. ↑ Murakami, Hiroshi; Asahi, Tsunemori; Amano, Hiroshi; Hiramatsu, Kazumasa; Sawaki, Nobuhiko; Akasaki, Isamu (1991). "Growth of Si-doped AlxGa1–xN on (0001) sapphire substrate by metalorganic vapor phase epitaxy". Journal of Crystal Growth. 115 (1–4). Elsevier BV: 648–651. Bibcode:1991JCrGr.115..648M. doi:10.1016/0022-0248(91)90820-u. ISSN 0022-0248.
  18. ↑ Amano, Hiroshi; Asahi, Tsunemori; Akasaki, Isamu (February 20, 1990). "Stimulated Emission Near Ultraviolet at Room Temperature from a GaN Film Grown on Sapphire by MOVPE Using an AlN Buffer Layer". Japanese Journal of Applied Physics. 29 (Part 2, No. 2). Japan Society of Applied Physics: L205–L206. Bibcode:1990JaJAP..29L.205A. doi:10.1143/jjap.29.l205. ISSN 0021-4922. S2CID 120489784.
  19. ↑ Akasaki, Isamu; Amano, Hiroshi; Sota, Shigetoshi; Sakai, Hiromitsu; Tanaka, Toshiyuki; Koike, Masayoshi (November 1, 1995). "Stimulated Emission by Current Injection from an AlGaN/GaN/GaInN Quantum Well Device". Japanese Journal of Applied Physics. 34 (11B). Japan Society of Applied Physics: L1517–L1519. Bibcode:1995JaJAP..34L1517A. doi:10.7567/jjap.34.l1517. ISSN 0021-4922. S2CID 122963134.
  20. ↑ Itoh, Kenji; Kawamoto, Takeshi; Amano, Hiroshi; Hiramatsu, Kazumasa; Akasaki, Isamu (September 15, 1991). "Metalorganic Vapor Phase Epitaxial Growth and Properties of GaN/Al0.1Ga0.9N Layered Structures". Japanese Journal of Applied Physics. 30 (Part 1, No. 9A). Japan Society of Applied Physics: 1924–1927. Bibcode:1991JaJAP..30.1924I. doi:10.1143/jjap.30.1924. ISSN 0021-4922. S2CID 123428785.
  21. ↑ Takeuchi, Tetsuya; Sota, Shigetoshi; Katsuragawa, Maki; Komori, Miho; Takeuchi, Hideo; Amano, Hiroshi; Akasaki, Isamu (April 1, 1997). "Quantum-Confined Stark Effect due to Piezoelectric Fields in GaInN Strained Quantum Wells". Japanese Journal of Applied Physics. 36 (Part 2, No. 4A). Japan Society of Applied Physics: L382–L385. Bibcode:1997JaJAP..36L.382T. doi:10.1143/jjap.36.l382. ISSN 0021-4922. S2CID 95930600.
  22. ↑ Takeuchi, Tetsuya; Amano, Hiroshi; Akasaki, Isamu (February 15, 2000). "Theoretical Study of Orientation Dependence of Piezoelectric Effects in Wurtzite Strained GaInN/GaN Heterostructures and Quantum Wells". Japanese Journal of Applied Physics. 39 (Part 1, No. 2A). Japan Society of Applied Physics: 413–416. Bibcode:2000JaJAP..39..413T. doi:10.1143/jjap.39.413. ISSN 0021-4922. S2CID 121954273.
  23. ↑ "Nagoya University profile 2008" (PDF). nagoya-u.ac.jp. Archived from the original (PDF) on October 17, 2012.
  24. ↑ "Nobel-Winning Scientist Isamu Akasaki Dies at 92". nippon.com. April 2, 2021. Archived from the original on April 2, 2021. Retrieved April 2, 2021.
  25. ↑ "IEEE Andrew S. Grove Award Recipients" (PDF). IEEE. Archived from the original (PDF) on July 4, 2019. Retrieved July 28, 2020.
  26. ↑ "Optoelectronics winners". www.rankprize.org. Archived from the original on June 14, 2025. Retrieved July 11, 2020.
  27. ↑ "Successive Recipients of C&C Prize". NEC C&C Foundation. Archived from the original on September 28, 2025. Retrieved December 15, 2025.
  28. ↑ "ECS SSS&T Award". www.electrochem.org. Archived from the original on October 12, 2014. Retrieved November 10, 2015.
  29. ↑ "The Asahi Prize (English version)". The Asahi Shimbun. Archived from the original on January 8, 2025. Retrieved January 8, 2025.
  30. ↑ "Recipient: 2006 John Bardeen Award". TMS. Archived from the original on March 4, 2016. Retrieved November 10, 2015.
  31. ↑ "Isamu Akasaki". Inamori Foundation. Archived from the original on March 4, 2016. Retrieved November 10, 2015.
  32. ↑ "IEEE Edison Medal Recipients" (PDF). IEEE. Archived (PDF) from the original on December 3, 2024. Retrieved December 10, 2024.
  33. ↑ "Karl Ferdinand Braun Award". Society for Information Display. Archived from the original on September 23, 2025. Retrieved June 9, 2022.
  34. ↑ Ainsworth, Susan J. (January 7, 2015). "Pioneers Of Light-Emitting Diodes Honored With 2015 Charles Stark Draper Prize". Chemical & Engineering News. Archived from the original on November 8, 2020. Retrieved September 19, 2022.
  35. ↑ "Chanda Kochhar among three Indians get Asia Game Changer awards". The Economic Times. September 16, 2015. Archived from the original on September 21, 2015. Retrieved October 28, 2020.
  36. ↑ "The Asian Scientist 100". Asian Scientist. Retrieved March 13, 2025.
  37. ↑ "LED Lighting". qeprize.org. Archived from the original on June 24, 2025. Retrieved December 8, 2025.
  38. ↑ "Fellow Class of 1999". IEEE. Archived from the original on December 26, 2012. Retrieved February 23, 2013.
  39. ↑ "Dr. Isamu Akasaki". www.nae.edu. Archived from the original on April 9, 2025. Retrieved November 10, 2015.
  40. ↑ "Novelist, LED developer awarded". News On Japan. October 26, 2011. Retrieved March 1, 2013.{{cite news}}: CS1 maint: deprecated archival service (link)Category:CS1 maint: deprecated archival service

Further reading

  • Insights & Enterprise in PHOTONICS SPECTRA, 54, November 2004.
  • Materials Research Society Symposium Proceedings, Volume 639 (2000), pp. xxiii–xxv.
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