New publication on optimising and controlling grayscale lithography

​We’re excited to share a new open‑access publication titled Standing waves induced surface roughness in grayscale lithography, released by SCARBOn partners at UGA, UGA‑LTM, and ONERA.

​This study brings fresh insight into the control of surface roughness when making by grayscale lithography ultra‑small silicon staircase structures – the micro‑optical features at the heart of Nanocarb compact imaging SWIR spectrometer, that is developed in SCARBOn project to detect greenhouse gases like CO₂ and CH₄ with high precision.

​The authors show that standing waves resulting from optical reflection at the Silicon/resist interface induces subtle light effects inside the photoresist and therefore small variations in surface smoothness, which remains visible after etching. Understanding this behavior helps us to improve the fabrication process and ensure long‑term stability of SCARBOn’s optical components.​

A big thank you to the author team for this excellent work: Melissa Hedir, Axel Picca, Nadine Gerges, Ayoub Rahali, Lou Denaix, Alexis Carcenac, Silvère Gousset, Yann Ferrec, Cécile Gourgon.