Jun-ichi Nishizawa
西澤 潤一
BornSeptember 12, 1926
DiedOctober 21, 2018(2018-10-21) (aged 92)
Sendai, Miyagi Prefecture, Japan
Alma materTohoku University
AwardsIEEE Edison Medal (2000)
Order of Culture
Scientific career
InstitutionsTohoku University
Iwate Prefectural University
Tokyo Metropolitan University
Sophia University
Layers of a PIN diode. (+ -)
The PIN photodiode was invented by Jun-ichi Nishizawa in 1950.

Jun-ichi Nishizawa (西澤 潤一, Nishizawa Jun'ichi, September 12, 1926 – October 21, 2018)[1] was a Japanese engineer and inventor. He is known for his electronic inventions since the 1950s, including the PIN diode, static induction transistor, static induction thyristor, SIT/SITh. His inventions contributed to the development of internet technology and the information age.[2]

He was a professor at Sophia University. He is considered the "Father of Japanese Microelectronics".


Nishizawa was born in Sendai, Japan, on September 12, 1926. He earned a B.S. in 1948, and a Doctor of Engineering degree in 1960, from Tohoku University.

In 1953, he joined the Research Institute of Electrical Communication at Tohoku University. He became a professor there and was appointed director to two research institutes. From 1990 to 1996, Nishizawa served as the President of Tohoku University.

He became the president of Iwate Prefectural University in 1998.


In 1950, the static induction transistor was invented by Jun-ichi Nishizawa and Y. Watanabe.[3] The PIN photodiode was also invented by Nishizawa and his colleagues in 1950.[4]

In 1952, he invented the avalanche photodiode.[5] He then invented a solid-state maser in 1955.[5] This was followed by his proposal for a semiconductor optical maser in 1957, a year before Schawlow and Townes's first paper on optical masers.[5][6][7]

While working at Tohoku University, he proposed fiber-optic communication, the use of optical fibers for optical communication, in 1963.[8] Nishizawa invented other technologies in the 1960s that contributed to the development of optical fiber communications, such as the graded-index optical fiber as a channel for transmitting light from semiconductor lasers.[9][10] He patented the graded-index optical fiber in 1964.[2]

In 1971, he invented the static induction thyristor.[5][11]


Nishizawa was a Life Fellow of the IEEE. He is a Fellow of several other institutions, including the Physical Society, the Russian Academy of Sciences, and the Polish Academy of Sciences. Nishizawa was decorated with Order of Culture by the emperor of Japan in 1989.[12] He also received the Japan Academy Prize (1974),[12] IEEE Jack A. Morton Award (1983),[13] the Honda Prize and the Laudise Prize of the International Organization for Crystal Growth (1989).[14] IEEE conferred the Edison Medal on him in 2000,[15] and introduced the IEEE Jun-ichi Nishizawa Medal in 2002.[16] He has more than a thousand patents registered under his name.[1]


  1. ^ a b "Former Tohoku U. president Junichi Nishizawa, known as 'Mr. Semiconductor,' dies at 92". The Mainichi. October 26, 2018. Retrieved January 15, 2019.
  2. ^ a b The Third Industrial Revolution Occurred in Sendai, Soh-VEHE International Patent Office, Japan Patent Attorneys Association
  3. ^ McCluskey, F. Patrick; Podlesak, Thomas; Grzybowski, Richard, eds. (1996). High Temperature Electronics (illustrated ed.). CRC Press. p. 82. ISBN 9780849396236.
  4. ^ Dummer, G. W. A. (2013). Electronic Inventions and Discoveries: Electronics from Its Earliest Beginnings to the Present Day (3rd, revised ed.). Elsevier. p. 137. ISBN 9781483145211.
  5. ^ a b c d Jun-ichi Nishizawa: Engineer, Sophia University Special Professor (interview), Japan Quality Review, 2011.
  6. ^ Nishizawa, Jun-ichi (December 2009). "Extension of frequencies from maser to laser". Proc Jpn Acad Ser B Phys Biol Sci. 85 (10): 454–465. doi:10.2183/pjab.85.454. PMC 3621550. PMID 20009378.
  7. ^ Schawlow, Arthur; Townes, Charles (1958). "Infrared and Optical Masers". Physical Review. 112 (6): 1940–1949. Bibcode:1958PhRv..112.1940S. doi:10.1103/PhysRev.112.1940.
  8. ^ Nishizawa, Jun-ichi & Suto, Ken (2004). "Terahertz wave generation and light amplification using Raman effect". In Bhat, K. N. & DasGupta, Amitava (eds.). Physics of semiconductor devices. New Delhi, India: Narosa Publishing House. p. 27. ISBN 81-7319-567-6.
  9. ^ "Optical Fiber". Sendai New. Archived from the original on September 29, 2009. Retrieved April 5, 2009.
  10. ^ Kowalenko, Kathy (June 1, 2003). "New Medal Honors Japanese Microelectrics Industry Leader". Institute of Electrical and Electronics Engineers. Archived from the original on September 15, 2009.[verification needed]
  11. ^ Dummer, G. W. A. (2013). Electronic Inventions and Discoveries: Electronics from Its Earliest Beginnings to the Present Day (3rd, revised ed.). Elsevier. p. 231. ISBN 9781483145211.
  12. ^ a b "Prize Winners" (PDF). Tohoku University.
  13. ^ "IEEE Jack A. Morton Award Recipients" (PDF). IEEE. Retrieved January 15, 2019.
  14. ^ "Prizes". International Organization for Crystal Growth. Archived from the original on November 25, 2018. Retrieved January 15, 2019.
  15. ^ "IEEE Edison Medal Recipients" (PDF). IEEE.
  16. ^ "IEEE Jun-ichi Nishizawa Medal". IEEE. Retrieved January 15, 2019.