Technique would allow the addition of optical communication components to existing chips with little modification of their designs.
Two and a half years ago, a team of researchers led by groups at MIT, the University of California at Berkeley, and Boston University announced a milestone: the fabrication of a working microprocessor, built using only existing manufacturing processes, that integrated electronic and optical components on the same chip.
The researchers’ approach, however, required that the chip’s electrical components be built from the same layer of silicon as its optical components. That meant relying on an older chip technology in which the silicon layers for the electronics were thick enough for optics.
In the latest issue of Nature, a team of 18 researchers, led by the same MIT, Berkeley, and BU groups, reports another breakthrough: a technique for assembling on-chip optics and electronics separately, which enables the use of more modern transistor technologies. Again, the technique requires only existing manufacturing processes.
“The most promising thing about this work is that you can optimize your photonics independently from your electronics,” says Amir Atabaki, a research scientist at MIT’s Research Laboratory of Electronics and one of three first authors on the new paper. “We have different silicon electronic technologies, and if we can just add photonics to them, it’d be a great capability for future communications and computing chips. For example, now we could imagine a microprocessor manufacturer or a GPU manufacturer like Intel or Nvidia saying, ‘This is very nice. We can now have photonic input and output for our microprocessor or GPU.’ And they don’t have to change much in their process to get the performance boost of on-chip optics.”
thumbnail courtesy of news.mit.edu