innovation for industry
Optics and photonics
1) What is photonics for?
Sylvie Menezo: Historically, optical data transmission has been used in telecommunications to send data over very long distances, from the hundreds to even the thousands of kilometers. Today, 80% of data transmission takes place over very short distances—less than two kilometers—inside data centers. For this type of application, cost and energy consumption are crucial factors. At the same time, the volumes of data transmitted are growing constantly, so performance improvements are also needed.
2) What are the current technological hurdles to better-performing solutions and how will they be addressed?
Sylvie Menezo:In the past, indium phosphide (InP) technology has generally been used in telecommunications. However, due to the fact that the components—the laser, modulator, and photodetector—must be fabricated separately and assembled by hand, this technology is expensive. Scintil Photonics is looking at a silicon technology initially developed by Leti as a way to leverage existing microelectronics production processes. The challenge is that we currently do not know how to fabricate lasers on silicon.
So, the idea is to have all of the components except for the laser fabricated by commercial foundries using silicon microelectronics processes. We will then use an automated pick-and-place molecular bonding process to deposit the indium phosphide on the circuits. The final step will be to mass-fabricate the lasers on the indium phosphide using conventional microelectronics processes.
All of the components required for optical communications will be integrated onto a single silicon circuit.
3) What did Leti contribute? What is the outlook moving forward?
Scintil Photonics is leveraging Leti developments that have made it possible to integrate lasers into InP semiconductor materials on silicon circuits. The mass fabrication of lasers on silicon enables us to reduce costs, size, and energy consumption. So, we can integrate several laser sources on a single circuit. And, because each laser transmits its own flow of data, this advance radically increases data transmission capacities.
In November 2018 I founded Scintil Photonics with Pascal Langlois, who had been the CEO of Tronics before it was acquired by TDK. We are currently still in our incubation phase. Now that we have completed our demonstrator systems, we are in talks with several foundries about prototyping and producing our first circuits, which will achieve data transmission speeds of 800 Gbit/s.
CEA is a French government-funded technological research organisation in four main areas: low-carbon energies, defense and security, information technologies and health technologies. A prominent player in the European Research Area, it is involved in setting up collaborative projects with many partners around the world.