E. Fred Schubert

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E. Fred Schubert
2023-May--IMG 8177--EFS--SQ-04.jpg
Schubert in 2023
BornFebruary 8, 1956
Stuttgart, Germany
NationalityGerman (by birth), U.S.A. (naturalized in 1996)
Alma mater University of Stuttgart
Known forTechnical contributions to LEDs and semiconductor technology
Scientific career
FieldsMicroelectronics
Institutions MPI FKF
Bell Labs
BU
RPI
Doctoral advisor Klaus H. Ploog

Eric Fred Schubert. [1] is an electrical engineer, researcher, educator, and inventor (born on February 8, 1956, in Stuttgart, Germany) [2] who made technical contributions to semiconductor devices, particularly LEDs. He has authored four books (including a standard textbook on LEDs), 39 U.S. patents, and more than 300 technical papers. [3]

Contents

Life and professional career

Schubert was born as the fifth child of Physicist Konrad Schubert  [ de ] [4] and homemaker Martha Ruth (Reichert) Schubert. [2] In his youth, Schubert developed an interest in electrical circuits and built various transistor circuits such as flip-flop circuits. After completing high school in 1975, he studied Electrical Engineering at the University of Stuttgart, Stuttgart, Germany, and graduated with an M.S.E.E. degree (Elektroingenieur) in 1981. [5]

From 1981 to 1985, Schubert conducted research on III-V semiconductors under the guidance of Klaus Ploog  [ de ] at the MPI for Solid State Research in Stuttgart for which he was awarded a Ph.D. degree (Doktoringenieur) from the University of Stuttgart. From 1985 to 1995, he was employed at AT&T Bell Laboratories in Holmdel and Murray Hill, NJ, initially as a post-doctoral fellow, and later as a Member of Technical Staff and Principal Investigator. From 1995 to 2002, he was on the faculty of Boston University in Boston, MA. [6] Since 2002, he has been on the faculty of Rensselaer Polytechnic Institute in Troy, NY [7] where he has served as Professor of Electrical, Computer, and Systems Engineering, as well as other positions including Professor of Physics, Constellation Professor, and Founding Director and Principal Investigator of the Smart Lighting Engineering Research Center funded by the NSF. [8] [9]

Technical contributions

Schubert made various contributions to LED research and development. [10] [11] During the transition from conventional incandescent and fluorescent lighting to present-day LED lighting, he showed that LED lighting technology has capabilities that transcend conventional lighting technologies. In particular, he showed that LED lighting sources can be controlled in terms of their spatial emission pattern, spectral composition, color temperature, temporal modularity, and polarization, thereby enabling "smart" lighting technologies. [12] The controllability of LED lighting sources enables energy savings as well as high flexibility when tailoring lighting for specific needs. [13] Schubert's contributions to LEDs include the commonly practiced roughening of semiconductor surfaces by crystallographic wet chemical etching to enhance light extraction in GaN LEDs. [14] His contributions also include the resonant cavity LED that is characterized by a narrow emission line and a spatially directed emission. Schubert wrote several editions of an LED textbook, titled Light Emitting Diodes, that has been translated into Russian, Japanese, and Korean. [15]

Schubert contributed to the understanding of the optical emission from semiconductor alloys, such as AlGaAs and InGaN. The optical emission from semiconductor alloys is spectrally broadened due to random fluctuations of the alloy's chemical composition. The spectral broadening is known as alloy broadening. [16]

Semiconductors are commonly doped with doping atoms that determine the electrical conductivity of the semiconductors. Schubert developed the delta doping technique where doping atoms are confined to one or a few atomic layers of the semiconductor crystal. [17] Associated doping profiles can be described by the mathematical delta function. Delta doping profiles are a fundamental limit in the miniaturization of doping profiles in semiconductors.

Schubert developed low-refractive-index materials, a class of thin film materials that can have refractive indexes close to that of air. The thin films are nano-porous and for this reason have a refractive index lower than their dense counterparts. Using low-refractive-index materials, Schubert demonstrated AR coatings with a gradually changing refractive index. The coatings reflect no light. [18]

Books

Awards and distinctions

Related Research Articles

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References

  1. ↑ Erdmann Friedrich Schubert at birth, changed to Eric Fred Schubert during U.S. naturalization in 1996.
  2. 1 2 Marquis Who's Who (Marquis Who's Who Ventures, Berkeley Heights, NJ, 1996).
  3. ↑ "Schubert's Google Scholar profile" . Retrieved May 8, 2023.
  4. ↑ "Konrad Schubert (1915-1992) Springer Communications" (PDF). Journal of Phase Equilibria. 13 (5). doi:10.1007/BF02665758. S2CID   95296968 . Retrieved May 8, 2023.
  5. ↑ Schubert, E.F.; Fischer, A.; Ploog, K. (1986). "The delta-doped field-effect transistor". IEEE Transactions on Electron Devices. ED-33 (5): 625–632. Retrieved December 29, 2023.
  6. ↑ "Schubert on the faculty of Boston University" . Retrieved May 8, 2023.
  7. ↑ "Schubert on the faculty of RPI". Archived from the original on April 24, 2023. Retrieved May 8, 2023.
  8. ↑ "NSF Smart Lighting Engineering Research Center" . Retrieved May 8, 2023.
  9. ↑ "SPIE announcement of Smart Lighting Engineering Research Center" . Retrieved May 8, 2023.
  10. ↑ "Schubert cited in background of 2014 Nobel Prize" . Retrieved May 9, 2023.
  11. ↑ "Light-emitting diodes hit the centenary milestone, Compound Semiconductor Magazine, 15th October 2007" . Retrieved May 9, 2023.
  12. ↑ Schubert, E. Fred; Kim, Jong Kyu (2005). "Solid-State Light Sources Getting Smart". Science. 308 (5726): 1274–1278. Bibcode:2005Sci...308.1274S. doi:10.1126/science.1108712. PMID   15919985. S2CID   6354382 . Retrieved May 9, 2023.
  13. ↑ "The coming revolution in LED lighting, by the Optical Society of America" . Retrieved May 9, 2023.
  14. ↑ "Crystallographic wet chemical etching of III-nitride material, U.S. Patent 6,294,475" . Retrieved May 9, 2023.
  15. ↑ Schubert, E. Fred (2006). Light Emitting Diodes (2nd Edition), 422 pages, Cambridge University Press, Cambridge UK, ISBN 9780511790546, 2006. doi:10.1017/CBO9780511790546. ISBN   9780521865388 . Retrieved May 9, 2023.
  16. ↑ Schubert, E.F.; Göbel, E.O.; Horikoshi, Y.; Ploog, K.; Queisser, H.J. (1984). "Alloy broadening in photoluminescence spectra of AlxGa1−xAs". Physical Review B. 30 (2): 813–820. Bibcode:1984PhRvB..30..813S. doi:10.1103/PhysRevB.30.813 . Retrieved October 2, 2023.
  17. ↑ "Semiconductor devices with at least one monoatomic layer of doping atoms, U.S. Patent 4,882,609" . Retrieved May 9, 2023.
  18. ↑ "Materials that reflect no light, by Kevin Bullis in MIT Technology Review, March 6, 2007" . Retrieved May 9, 2023.
  19. ↑ https://spie.org/membership/member-recognition/spie-fellows/complete-list-of-spie-fellows?SSO=1
  20. ↑ [https://www.ieee.org/membership/fellows/fellows-directory.html
  21. ↑ "Discover award for Schubert's LED research" . Retrieved May 8, 2023.
  22. ↑ "BU Bridge article on Discover Magazine Award (2000)" . Retrieved May 8, 2023.
  23. ↑ https://www.optica.org/en-us/get_involved/awards_and_honors/fellow_members/
  24. ↑ "BU Bridge article on BU Provost Innovation Award (2001)" . Retrieved May 8, 2023.
  25. ↑ https://www.aps.org/programs/honors/fellowships/archive-all.cfm
  26. ↑ https://eds.ieee.org/education/distinguished-lecturer-mini-colloquia-program/distinguished-lecturer-listing
  27. ↑ https://www.ieee.org/membership/fellows/fellows-directory.html
  28. ↑ R&D Magazine and Micro/Nano Newsletter, July 2007 issue.
  29. ↑ "RPI article on Scientific American 50 Award (2007)" . Retrieved May 8, 2023.
  30. ↑ Editors’ Choice, Science Magazine, volume 319, page 1163 (February 2008).
  31. ↑ https://life.ieee.org/
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