Publications – 2021

Chen Shi, Victoria Andino-Pavlovsky, Stephen A. Lee, Tiago Costa, Jeffrey Elloian, Elisa E. Konofagou, and Kenneth L. Shepard, “Application of a sub-0.1-mm3 implantable mote for in vivo real-time wireless temperature sensing,” Science Advances (to appear)

“Electron beam lithography (EBL) is the state-of-the-art technique for rapid prototyping of nanometer-scale devices. Even so, processing speeds remain limited for the highest resolution patterning. Here, we establish Mr-EBL as the highest throughput negative tone electron-beamsensitive resist. The 10 μC cm−2 dose requirement enables fabricating a 100 mm2 photonic diffraction grating in a ten minute EBL process. Optimized processing conditions achieve a critical resolution of 75 nm with 3× faster write speeds than SU-8 and 1–2 orders of magnitude faster write speeds than maN-2400 and hydrogen silsesquioxane. Notably, these conditions significantly differ from the manufacturers’ recommendations for the recently commercialized Mr-EBL resist. We demonstrate Mr-EBL to be a robust negative etch mask by etching silicon trenches with aspect ratios of 10 and near-vertical sidewalls. Furthermore, our optimized processing conditions are suitable to direct patterning on integrated circuits or delicate nanofabrication stacks, in contrast to other negative tone EBL resists. In conclusion, Mr-EBL is a highly attractive EBL resist for rapid prototyping in nanophotonics, MEMS, and fluidics.”

Sajjad Moazeni, Eric H. Pollmann, Vivek Boominathan, Filipe A.Cardoso,Jacob T. Robinson, Ashok Veeraraghavan, Kenneth L. Shepard, A Mechanically Flexible Implantable Neural Interface for Computational Imaging and Optogenetic Stimulation over 5.4×5.4mm2 FoV, International Solid-State Circuits Conference, 2021

Sajjad Moazeni, Kevin Renehan, Eric Pollmann, Kenneth Shepard, Integrated-Circuit Node for Time-Domain Near-infrared Diffuse Optical Tomography Imaging Arrays with On-chip Histogramming and Integrated VCSELs, IEEE Custom Integrated Circuits Conference (CICC), 2021 (to appear)