SUCCESS STORY at EPFL in Lausanne, Switzerland, one of Europe’s most active science and technology institutions.

Interview with Dr. Marta Divall – Laboratory Manager

Tell us about your role at EPFL. Which field are you specialized in?

I am Dr. Marta Divall, Laboratory Manager in the Laboratory of Photonic integrated circuits and Quantum Measurements (LPQM) at EPFL, led by Professor Kippenberg.

Our research is focused on cutting edge technologies in integrated photonics, on chip lasers, amplifiers and frequency combs as well as on superconducting circuits. I am part of the group specializing in integrated photonics, exploring new material platforms based on Lithium niobate and Lithium tantalate and other active crystals.

The SET ACCµRA OPTO Flip-Chip Bonder was purchased as a platform tool that is accessible to all users in the Center of Micro and Nanotechnology (CMi) at EPFL cleanroom. As a result, after more than a year of use, we have trained several researchers from labs across a wide range of disciplines, including integrated circuits, microfluidics, and heterogeneous material integration. They all benefit from the capability of the tool to develop In or Sn bump bonding, dielectric bonding or epoxy bonding separately.

What type of applications do you develop with the SET ACCµRA OPTO Flip-Chip Bonder?

In our laboratory, we use the SET ACCµRA OPTO Flip-Chip Bonder primarily for advanced photonic and electronic packaging. We have successfully developed a high-speed electrical packaging process using flip-chip gold-to-gold bonding, achieving bandwidths up to 110 GHz without introducing significant additional loss.

Currently, we are working on developing electro-optic co-packaging technology. This involves creating a high-efficiency optical transition between the bonded chip and the substrate while preserving the excellent electrical performance we have already demonstrated.

Due to the small mode field diameter in our optical devices, precise alignment is critical and has to happen on sub-wavelength scale. The high alignment accuracy of the SET ACCµRA OPTO Flip-Chip Bonder allows us to reproducibly and reliably test various design iterations with confidence. We are still exploring the compatible technique for both electrical and optical devices.