Milton Feng

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Milton Feng co-created the first transistor laser, working with Nick Holonyak in 2004. The paper discussing their work was voted in 2006 as one of the five most important papers published by the American Institute of Physics since its founding 75 years ago. In addition to the invention of transistor laser, he is also well known for inventions of other "major breakthrough" devices, including the world's fastest transistor and light-emitting transistor (LET). As of May, 2009 he is a professor at the University of Illinois at Urbana–Champaign and holds the Nick Holonyak Jr. Endowed Chair Professorship.

Contents

Feng was born and raised in Taiwan. [1]

Inventions

World's fastest transistor

In 2003, Milton Feng and his graduate students Walid Hafez and Jie-Wei Lai broke the record for the world's fastest transistor. Their device, made of indium phosphide and indium gallium arsenide with 25 nm thick base and 75 nm thick collector, marked a frequency of 509 GHz, which was 57 GHz faster than the previous record.

In 2005, they succeeded in fabricating a device at Micro and Nanotechnology Laboratory to break their own record, reaching 604 GHz.

In 2006, Feng and his other graduate student William Snodgrass fabricated an indium phosphide and indium gallium arsenide device with 12.5 nm thick base, operating at 765 GHz at room temperature and 845 GHz at -55 °C. [2] [3]

Light-emitting transistor

Reported in the January 5 issue of the journal Applied Physics Letters in 2004, Milton Feng and Nick Holonyak, the inventor of the first practical light-emitting diode (LED) and the first semiconductor laser to operate in the visible spectrum, made the world's first light-emitting transistor. This hybrid device, fabricated by Feng's graduate student Walid Hafez, had one electrical input and two outputs (electrical output and optical output) and operated at a frequency of 1 MHz. The device was made of indium gallium phosphide, indium gallium arsenide, and gallium arsenide, and emitted infrared photons from the base layer. [4] [5]

Transistor laser

Described in the November 15 issue of the journal Applied Physics Letters in 2004, Milton Feng, Nick Holonyak, postdoctoral research associate Gabriel Walter, and graduate research assistant Richard Chan demonstrated operation of the first heterojunction bipolar transistor laser by incorporating a quantum well in the active region of a light-emitting transistor. As with a light-emitting transistor, the transistor laser was made of indium gallium phosphide, indium gallium arsenide, and gallium arsenide, but emitted a coherent beam by stimulated emission, which differed from their previous device that only emitted incoherent photons. Despite their success, the device was not useful for practical purposes since it only operated at low temperatures – about minus 75  Celsius degrees.

Within a year, though, the researchers finally fabricated a transistor laser operating at room temperature by using metal organic chemical vapor deposition (MOCVD), as reported in the September 26 issue of the same journal. At this time, the transistor laser had a 14-layer structure including aluminium gallium arsenide optical confining layers and indium gallium arsenide quantum wells. The emitting cavity was 2,200 nm wide and 0.85 mm long, and had continuous modes at 1,000 nm. In addition, it had a threshold current of 40 mA and direct modulation of the laser at 3 GHz.

Recognition

See also

Related Research Articles

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<span class="mw-page-title-main">Gallium arsenide</span> Chemical compound

Gallium arsenide (GaAs) is a III-V direct band gap semiconductor with a zinc blende crystal structure.

<span class="mw-page-title-main">Nick Holonyak</span> American engineer (1928–2022)

Nick Holonyak Jr. was an American engineer and educator. He is noted particularly for his 1962 invention and first demonstration of a semiconductor laser diode that emitted visible light. This device was the forerunner of the first generation of commercial light-emitting diodes (LEDs). He was then working at a General Electric Company research laboratory near Syracuse, New York. He left General Electric in 1963 and returned to his alma mater, the University of Illinois at Urbana-Champaign, where he later became John Bardeen Endowed Chair in Electrical and Computer Engineering and Physics.

<span class="mw-page-title-main">Monolithic microwave integrated circuit</span>

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<span class="mw-page-title-main">Indium phosphide</span> Chemical compound

Indium phosphide (InP) is a binary semiconductor composed of indium and phosphorus. It has a face-centered cubic ("zincblende") crystal structure, identical to that of GaAs and most of the III-V semiconductors.

SiGe, or silicon–germanium, is an alloy with any molar ratio of silicon and germanium, i.e. with a molecular formula of the form Si1−xGex. It is commonly used as a semiconductor material in integrated circuits (ICs) for heterojunction bipolar transistors or as a strain-inducing layer for CMOS transistors. IBM introduced the technology into mainstream manufacturing in 1989. This relatively new technology offers opportunities in mixed-signal circuit and analog circuit IC design and manufacture. SiGe is also used as a thermoelectric material for high-temperature applications (>700 K).

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Indium gallium arsenide (InGaAs) is a ternary alloy of indium arsenide (InAs) and gallium arsenide (GaAs). Indium and gallium are group III elements of the periodic table while arsenic is a group V element. Alloys made of these chemical groups are referred to as "III-V" compounds. InGaAs has properties intermediate between those of GaAs and InAs. InGaAs is a room-temperature semiconductor with applications in electronics and photonics.

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Indium arsenide antimonide phosphide is a semiconductor material.

Transistor laser is a semiconductor device that functions as a transistor with an electrical output and an optical output, as opposed to the typical two electrical outputs. This optical output separates it from typical transistors and, because optical signals travel faster than electrical signals, has the potential to speed up computing immensely. Researchers who discovered the transistor laser developed a new model of Kirchhoff's current law to better model the behavior of simultaneous optical and electrical output.

A light-emitting transistor or LET is a form of transistor that emits light. Higher efficiency than light-emitting diode (LED) is possible.

James J. Coleman is an electrical engineer who worked at Bell Labs, Rockwell International, and the University of Illinois, Urbana. He is best known for his work on semiconductor lasers, materials and devices including strained-layer indium gallium arsenide lasers and selective area epitaxy. Coleman is a Fellow of the IEEE and a member of the US National Academy of Engineering.

References

  1. "Milton Feng". Electrical & Computing Engineering. University of Illinois. Retrieved 2020-04-06.
  2. Kloeppel, James E. (Dec 11, 2006). "World's fastest transistor approaches goal of terahertz device" (Press release). Champaign, Ill.: University of Illinois at Urbana–Champaign. University of Illinois News Bureau. Retrieved 2018-02-21.
  3. Snodgrass, William; Hafez, Walid; Harff, Nathan; Feng, Milton (2006). "Pseudomorphic InP/InGaAs Heterojunction Bipolar Transistors (PHBTS) Experimentally Demonstrating fT = 765 GHZ at 25 °C Increasing to fT = 845 GHZ at -55 °C". 2006 International Electron Devices Meeting (IEDM '06). 2006 IEEE International Electron Devices Meeting. December 10–13, 2006. San Francisco, CA. pp. 1–4. doi:10.1109/IEDM.2006.346853. ISBN   1-4244-0438-X. S2CID   27243567.
  4. Justin Mullins (January 2004). "First Light-Emitting Transistor: The inventor of the LED makes another optoelectronics breakthrough". IEEE Spectrum . Retrieved 2020-04-06.
  5. Kloeppel, James E. "New light-emitting transistor could revolutionize electronics industry". news.illinois.edu. Retrieved 2020-04-06.

Further reading