14 DAY TRIAL // A group of scientists managed to achieve an important milestone in the attempt to develop a new generation of microprocessors, when expert succeeded in growing nanolasers on a silicon surface.
This brings new hope that the processors of the future will contain built-in nanoscale lasers, that will considerably augment their efficiency and speed. New optoelectronic chips for powerful biochemical sensors could also become a reality.
In charge of the new investigation were researchers from the University of California in Berkeley (UCB). They published a paper describing the details of their achievement in the February 6 advanced online issue of the esteemed scientific journal Nature Photonics.
The reason why this study is so important is because silicon is literally the foundation of modern electronics, the material on which all microchips are built. Its properties drive the world of today.
“Our results impact a broad spectrum of scientific fields, including materials science, transistor technology, laser science, optoelectronics and optical physics,” explains Connie Chang-Hasnain.
The expert, who holds an appointment as a professor of electrical engineering and computer sciences at UCB, was also the principal investigator of the new research, Science Blog reports.
She explains that research groups around the world are currently looking for methods to inscribe data on light particle, rather than on electrons. Light can carry information much more efficiently than electrical current can.
Silicon, for all its other values, is deficient at producing light. As such, for the new study, investigators used a class of materials called three-five (III-V). These semiconductors are widely used to create lasers and light-emitting diodes (LED), as well as other light-based components.
“Growing III-V semiconductor films on silicon is like forcing two incongruent puzzle pieces together” explains UCB graduate student in electrical engineering and computer sciences Roger Chen.
“It can be done, but the material gets damaged in the process,” adds Chen, who was also the lead author of the Nature Photonics paper.
“Today’s massive silicon electronics infrastructure is extremely difficult to change for both economic and technological reasons, so compatibility with silicon fabrication is critical,” Chang-Hasnain adds.
“One problem is that growth of III-V semiconductors has traditionally involved high temperatures, that would destroy the electronics. Meanwhile, other integration approaches have not been scalable,” she goes on to say.
The path the team used to circumvent this problem was fairly simple – the experts used nanopillars made of indium gallium arsenide. This allowed the process to be carried out at 400 degrees Celsius.
The new study was sponsored by a Department of Defense (DOD) National Security Science and Engineering Faculty Fellowship, and by the US Defense Advanced Research Projects Agency (DARPA).