Optical communications have revolutionized remote data transmission, but the scale for microchips is more complex. Now, however, the new technology makes it possible to integrate optical components into general purpose chips using the production process and standard materials.
Light can carry data faster than electrical connections, which makes it very attractive to chip manufacturers who want to increase the speed of their devices. And, unlike cables, it also produces very little heat, which is significant, given the enormous server storage costs.
But you can not manipulate light like electricity, and technology companies have spent most of the century to improve their technology in the field of electronics. In order not to reinvent the wheel, interest in silicon has grown - an attempt to use the semiconductor industry's favorite materials to make optical circuits.
Some progress has been made, but despite the general materials, the processes required to make electronics and photonics are different. This means combining it into one and the same chip is difficult, therefore some such devices are usually relatively expensive.
That changed two and a half years ago, when researchers at the Massachusetts Institute of Technology, the University of California at Berkeley and Boston University have announced that they have successfully built a microprocessor that combines electronic and optical components using existing production processes.
They build their device on silicon wafers, where there is a layer of glass made of silicon dioxide beneath the top layer of silicon. This is a material commonly used for silicon photonics and for some high-performance electronic chips, but much more expensive than bulk silicon used for most microchips.
Now, the same researchers are presenting new techniques in the journal Nature, which allows combined electronics and photonics to use the same inexpensive source materials and processes as conventional microchips. They developed a method to add silicon fragments of silicon dioxide to bulk silicon and then store a thin film of polycrystalline silicon from above. Thereafter, the film can be made both in photonic components on top of broken glass, and in electronic components on top of bulk silicon.
In addition to using much cheaper source materials, the use of new technologies in standard manufacturing processes means that chipmakers interested in adding photonic components to their devices do not need to do more work. "We can imagine microprocessor manufacturers or manufacturers of GPUs, like Intel or Nvidia, saying:" Now we have photon and output inputs for our microprocessors and graphics processors.
"And they need not change much in the process to improve embedded optical performance" - says researcher from the research laboratory of the Massachusetts Institute of Technology's Amir Atabaki.When making both sets of components of the same material does not require compromise.
With polysilicon, there is a trade-off between optical and electrical efficiency, so it needs considerable optimization to find the right combination of silicon type, settling method and temperature as well as processing time. Goran Mashanovich, a professor at the University of Southampton, who works on Silicon Photonics, also notes that the microchips constructed by researchers use 65 nanometer transistor processes.
This technology emerged in 2006, and the semiconductor giant has now advanced to the 10-nanometer process, so the success of the approach will likely depend on whether it can be reduced even more. Ayar Labs aims at an intensive energy data center, where the introduction of new inexpensive methods can reduce energy use by 30-50 percent. They are also trying to increase the speed and efficiency of supercomputers.
There is still no sign of how fast a new approach to mass silicon research can be commercialized, but it can have a bigger effect, as it can use low cost and large supply chains of the existing semiconductor industry. Thus, silicon photonics can soon become integrated into our lives