This is our third episode of the chip series. In this episode, I will give you a review of the latest development of chip research and development from the perspective of processing technology.
Let me first ask you, what is the most valuable asset recognized globally in the 21st century?
It is data. At present, the data exchange between man-machine and machine-machine channels consumes about 9% of the world’s energy, and it is increasing at a rate of 20–30% every year. Moreover, the deployment of faster data networks and the Internet of Things (IoT) is increasing.
In this continuously connected world, data traffic has approached the bandwidth limit of communication networks, and high-speed optical communication is urgently needed.
Researchers at the Swiss Federal Institute of Technology Zurich have been working on a chip for nearly 20 years. On this chip, fast electronic signals can be directly converted into ultra-fast optical signals, with almost no signal quality loss.
By the way, this project is part of the European Horizon 2020 research project. This chip will greatly improve the efficiency of optical communication infrastructures (such as optical fiber networks) that use light to transmit data.
In the past, researchers have tried a method called “overall collaborative integration”. Simply put, it is to put the electronic chip and the photonic chip in layers and press them as tightly as possible to shorten the path and reduce the loss of signal quality. However, the monolithic method failed because the size of the photonic chip is much larger than that of the electronic chip, and it is impossible to combine them on the same chip.
In 2019, researchers at ETH Zurich overcame the size difference between photonics and electronics by replacing photonics with plasma. Since plasma chips are smaller than electronic chips, they can actually be manufactured more compactly.
Has this chip been commercialized? Here I introduce a startup company-Versics. It is led by Marc Reig Escalé, a physicist at the Institute of Quantum Electronics at ETH Zurich. Versics is his innovative project as an ETH Pioneer Fellowship. Versics is the abbreviation of “multifunctional optics”. The technology has many applications and can also be used for satellite communications in the future.
The first marketable prototype is expected to be launched at the end of this year, 2021.
We know that fiber optic cables are only half of the world of data traffic. The information needs to be encoded and decoded. This means that it must be “written” into the optical signal and then “read” again at the end.
Marc Reig Escalé and his colleagues found a way to “write” this information more efficiently than before. They chose the best materials in the fields of optics and microelectronics to manufacture microchips.
The first is silicon, which is the most important material in the computer industry. As a semiconductor, it is very suitable for building circuits, such as circuits on computer and mobile phone chips. In crystalline form, silicon is also used in optical chips to transmit light waves. This has practical advantages because the manufacture of micro-formats is already very mature in the field of microelectronics.
However, for optical purposes, silicon is far from the best choice. Lithium niobate offers more advantageous properties: for example, it can work in a wider range of optical frequencies. An important attribute of data processing is that this crystalline material can change the intensity of incident light according to an externally applied voltage. This allows electrical signals to be converted into optical signals.
This chip consumes less energy and processes signals at least twice as fast as commercial alternatives currently in existence.