ECE Alumnus Cho inducted into National Inventors Hall of Fame
Charlie Johnson, ECE ILLINOIS
- Alumnus Alfred Cho was inducted into the National Inventors Hall of Fame.
- Cho is known as "the father of molecular beam epitaxy."
- Cho holds 85 patents and has received the National Medal of Science and the National Medal of Technology.
Alfred Cho (BSEE ’60, MSEE ’61, PhD ’68) is no stranger to orange and blue. Cho’s older brother and sister both graduated from Illinois, and his uncle before them. By the time Cho came to Champaign-Urbana from Hong Kong to pursue his bachelor’s degree in electrical engineering, his Illinois roots already ran deep. And they only grew deeper as he went on to receive his bachelor’s, master’s, PhD, and later an Honorary Degree of Doctor of Engineering, all from the University of Illinois.
When it was announced in February that Cho was to be inducted into the US National Inventors Hall of Fame, it’s fair to say that the University of Illinois had something to do with it. “I was very fortunate to go to Illinois,” said Cho. “There are great facilities for students to have a hands-on experience at Illinois, but the really unique thing is the first class teachers they have. You really get a broad education that prepares students to face the ever changing world we have.”
The National Inventors Hall of Fame class of 2009 was inducted during a ceremony on May 2 in Mountain View, California. The inductees for 2009 include 15 other inventors from across the UnitedStates, including five who are being honored posthumously.
In celebration of the 50th anniversary of the invention of the integrated circuit, a device invented by Illinois alumnus Jack Kilby (BSEE ’47), the 2009 class of inductees represent those who have greatly advanced integrated circuit technology. “It’s a great honor to be inducted, and I feel very humbled to be selected,” said Cho. “I’m especially honored because the people nominated for the Inventors Hall of Fame are selected by the Patent and Trade Office based on the contributions of their patents to the nation’s welfare. I feel very honored that they consider my patents that useful.” Cho, who holds 85 patents, has also been the recipient of the National Medal of Science and the National Medal of Technology.
Cho, known as “the father of molecular beam epitaxy (MBE),” is being recognized for the development of MBE, a process by which crystals can be layered on top of one another, atom by atom, to achieve greater precision. The process of MBE begins when crystals are deposited or “spray painted” on a heated substrate. As more and more crystalline beams are deposited, layers begin to form atom by atom, which allows for extraordinary smoothness and control of the thickness and composition of the device’s structure. This control becomes a highly valuable tool when it comes to developing high quality photonic devices as well as in the field quantum research. “It has impacted science from fundamental science all the way to the application of useful devices that we use today,” said Cho.
The MBE technique is responsible for many firsts in the field of technology, including producing the first field effect transistor that operates at microwave frequencies and several types of diodes. MBE-fabricated devices are used in cell phones and are found in almost all CD and DVD players. And because MBE produces compounds not found in nature, it is useful in a variety of applications in the research of quantum physics.
Cho developed the MBE process while an engineer at AT&T Bell Laboratories (now Alcatel-Lucent’s Bell Laboratories) where he eventually became vice president of semiconductor research. Ironically, when Cho began developing the technology, most didn’t see a practical application for it. “When I started developing it 35 years ago, I was told that this technology was totally useless. That the layers were too thin to be commercially viable,” said Cho. “But, as time goes on, technology is always changing, and it shows you that if you have a vision and believe in yourself, good things can happen. Science is only limited by your imagination.”
Cho, along with his collaborators, have also worked on a new technology called the quantum-cascade laser which can be used to detect the presence of gas, pollutions, and explosives. He also envisions the technology having medical applications, possibly being small enough to act as a pocket sized “doctor on the go.” Just breath on the laser and it can give you a daily health reading, along with recommended medicines or activities. “You would basically have personal medical attention wherever you go,” said Cho.
Even though Cho has long since left the Urbana-Champaign area, he remains tied to the Fighting Illini. He met his wife, Mona Willoughby, while a student. Cho has also added several branches to his orange and blue family tree. Three of his four children also graduated from Illinois.
It gives new meaning to the phrase, “Illinois Loyalty.”