You are here : Home > AWARD – Congratulations to Jules Tillement for winning the best student paper prize!

News | Prizes and awards | Photonics

AWARD – Congratulations to Jules Tillement for winning the best student paper prize!

​​​​​​​​​​​​​​​​​​At the 2023 International Image Sensor Workshop!

Published on 26 March 2024

SWIR (short-wavelength infrared) sensors are sensitive to light in near-infrared light sources (between 1 and 2.5 µm). They are used in a multitude of applications, including for industrial imaging, medicine, security, and connected cars. They have a number of advantages over visible sensors, such as the capacity to detect photons at night or to see through fog or smoke. Improving SWIR sensor resolution while facilitating their industrial scale-up is a challenge. 

Indeed, making photosensitive elements smaller makes it possible to integrate a higher pixel density in the resulting sensor. This manufacturing process is compatible with a CMOS process, thereby allowing high-volume production. 

fter earning a Materials Engineering diploma from INSA Lyon, Jules Tillement did a final internship in a research laboratory specializing in image sensors. He was then recruited to pursue a doctorate at STMicroelectronics, in partnership with CEA-Leti.

​​As soon as a new sensor series is produced, a whole team is waiting in the wings, ready to test them.”

Jules offers a SWIR photodiode design that uses mesa architecture, whereby the active surface of a photodiode is protected by an InP integrated layer to mitigate deteriorations resulting from the manufacturing process. The structure makes it easier to reduce pixel/steps compared to traditional architectures found in scientific literature. Indium gallium arsenide (InGaAs) found in the sensor helps absorb wavelengths of interest at room temperature. The characterization of this design has shown promising results. For a 5 µm pixel/step, the measured quantum efficiency (QE) reaches 54%. With an antireflective coating, the QE could reach 77%. Cherry on the photonic pie, at 23 °C, it also has a very low dark current, reaching 5 nA/cm² at −0.1 V. Jules's work, at the junction between research and industry, contributes to advancing the state-of-the-art while taking into account the constraints of large-scale production.

​Not only was I proud of winning this award, but I was also pleased to have received a medal for the log toss game organized on the sidelines of the conference.

​Jules is considering integrating these photodiodes into a SWIR image sensor to improve the performance of current sensors. ​

Top page