Milton Feng
Encyclopedia
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.
. Their device, made of indium phosphide and indium gallium arsenide
with 25nm-thick base and 75nm-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 the following year, Feng and his other graduate student William Snodgrass fabricated a device with 12.5nm-thick base, operating at 765 GHz at room temperature and 845 GHz at minus 55 Celsius
degrees.
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.
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 in 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 2,200nm wide and 0.85mm long, and had continuous modes at 1,000nm. In addition, it had a threshold current of 40mA and direct modulation of the laser at 3 GHz.
Nick Holonyak
Nick Holonyak, Jr. invented the first practically useful visible LED in 1962 while working as a consulting scientist at a General Electric Company laboratory in Syracuse, New York and has been called "the father of the light-emitting diode"...
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
American Institute of Physics
The American Institute of Physics promotes science, the profession of physics, publishes physics journals, and produces publications for scientific and engineering societies. The AIP is made up of various member societies...
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
Transistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...
and light emitting transistor (LET). As of May, 2009 he is a professor at the University of Illinois at Urbana-Champaign
University of Illinois at Urbana-Champaign
The University of Illinois at Urbana–Champaign is a large public research-intensive university in the state of Illinois, United States. It is the flagship campus of the University of Illinois system...
and holds the Nick Holonyak
Nick Holonyak
Nick Holonyak, Jr. invented the first practically useful visible LED in 1962 while working as a consulting scientist at a General Electric Company laboratory in Syracuse, New York and has been called "the father of the light-emitting diode"...
Jr. Endowed Chair Professorship.
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 transistorTransistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...
. Their device, made of indium phosphide and indium gallium arsenide
Indium gallium arsenide
Indium gallium arsenide is a semiconductor composed of indium, gallium and arsenic. It is used in high-power and high-frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide. InGaAs bandgap also makes it the...
with 25nm-thick base and 75nm-thick collector, marked a frequency
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the 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 the following year, Feng and his other graduate student William Snodgrass fabricated a device with 12.5nm-thick base, operating at 765 GHz at room temperature and 845 GHz at minus 55 Celsius
Celsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
degrees.
Light emitting transistor
Reported in the January 5 issue of the journal Applied Physics LettersApplied Physics Letters
Applied Physics Letters is a peer-reviewed scientific journal that is published 52 times per year by the American Institute of Physics. Its focus is rapid publication and dissemination of new experimental and theoretical papers regarding applications of physics in all disciplines of science,...
in 2004, Milton Feng and Nick Holonyak
Nick Holonyak
Nick Holonyak, Jr. invented the first practically useful visible LED in 1962 while working as a consulting scientist at a General Electric Company laboratory in Syracuse, New York and has been called "the father of the light-emitting diode"...
, the inventor of the first practical light emitting diode (LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....
) and the first semiconductor laser to operate in the visible spectrum
Visible spectrum
The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm. In terms of...
, 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
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
of 1 MHz. The device was made of indium gallium phosphide
Indium gallium phosphide
Indium gallium phosphide , also called gallium indium phosphide , is a semiconductor composed of indium, gallium and phosphorus...
, indium gallium arsenide
Indium gallium arsenide
Indium gallium arsenide is a semiconductor composed of indium, gallium and arsenic. It is used in high-power and high-frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide. InGaAs bandgap also makes it the...
, and gallium arsenide, and emitted infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
photons from the base layer.
Transistor laser
Described in the November 15 issue of the journal Applied Physics LettersApplied Physics Letters
Applied Physics Letters is a peer-reviewed scientific journal that is published 52 times per year by the American Institute of Physics. Its focus is rapid publication and dissemination of new experimental and theoretical papers regarding applications of physics in all disciplines of science,...
in 2004, Milton Feng, Nick Holonyak
Nick Holonyak
Nick Holonyak, Jr. invented the first practically useful visible LED in 1962 while working as a consulting scientist at a General Electric Company laboratory in Syracuse, New York and has been called "the father of the light-emitting diode"...
, 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
Quantum well
A quantum well is a potential well with only discrete energy values.One technology to create quantization is to confine particles, which were originally free to move in three dimensions, to two dimensions, forcing them to occupy a planar region...
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 phosphide
Indium gallium phosphide , also called gallium indium phosphide , is a semiconductor composed of indium, gallium and phosphorus...
, indium gallium arsenide
Indium gallium arsenide
Indium gallium arsenide is a semiconductor composed of indium, gallium and arsenic. It is used in high-power and high-frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide. InGaAs bandgap also makes it the...
, and gallium arsenide, but emitted a coherent beam by stimulated emission
Stimulated emission
In optics, stimulated emission is the process by which an atomic electron interacting with an electromagnetic wave of a certain frequency may drop to a lower energy level, transferring its energy to that field. A photon created in this manner has the same phase, frequency, polarization, and...
, 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 in Celsius
Celsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
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
Aluminium gallium arsenide
Aluminium gallium arsenide is a semiconductor material with very nearly the same lattice constant as GaAs, but a larger bandgap. The x in the formula above is a number between 0 and 1 - this indicates an arbitrary alloy between GaAs and AlAs.The bandgap varies between 1.42 eV and 2.16 eV...
optical confining layers and indium gallium arsenide quantum wells. The emitting cavity was 2,200nm wide and 0.85mm long, and had continuous modes at 1,000nm. In addition, it had a threshold current of 40mA and direct modulation of the laser at 3 GHz.
Recognition
- In 2006, Transistor laser was the most popular top 10-science story (rank #4) on EurekAlert by American Association for the Advancement of ScienceAmerican Association for the Advancement of ScienceThe American Association for the Advancement of Science is an international non-profit organization with the stated goals of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsibility, and supporting scientific education and science outreach for the...
(AAAS). - In 2006, American Institute of PhysicsAmerican Institute of PhysicsThe American Institute of Physics promotes science, the profession of physics, publishes physics journals, and produces publications for scientific and engineering societies. The AIP is made up of various member societies...
selected "Room Temperature Continuous Wave Operation of a Heterojunction Bipolar Transistor Laser" as top 5 paper published in the 43 years history of Applied Physics LettersApplied Physics LettersApplied Physics Letters is a peer-reviewed scientific journal that is published 52 times per year by the American Institute of Physics. Its focus is rapid publication and dissemination of new experimental and theoretical papers regarding applications of physics in all disciplines of science,...
. - In 2005, Discover Magazine selected Transistor Laser as top 100 most important discovery.
See also
- Nick HolonyakNick HolonyakNick Holonyak, Jr. invented the first practically useful visible LED in 1962 while working as a consulting scientist at a General Electric Company laboratory in Syracuse, New York and has been called "the father of the light-emitting diode"...
- UIUC College of EngineeringUIUC College of EngineeringThe College of Engineering at the University of Illinois at Urbana–Champaign was first established in 1868, and is considered one of the original units of the school. The presence of a steam engine on the University's seal is a good clue as to the importance of the engineering program to the...
- University of Illinois at Urbana-ChampaignUniversity of Illinois at Urbana-ChampaignThe University of Illinois at Urbana–Champaign is a large public research-intensive university in the state of Illinois, United States. It is the flagship campus of the University of Illinois system...