Challenges of High-Resolution Electron Detection ASICs for SEM Microscopy

This paper presents a thorough investigation and evaluation of readout Application-Specific Integrated Circuits (ASICs) tailored for Backscattered Electron (BSE) detection in electron microscopy. The study explores the architecture, operational principles, and performance assessment of integrating and electron counting systems utilized for signal processing in BSE detection. Evaluation of the count rate capability of the readout ASICs is undertaken under diverse conditions, considering variables such as BSE energy, discriminator threshold levels, and preamplifier characteristics. Detailed methodologies for experimental qualification, including test setups, trigger mechanisms, and count rate capability assessments, are outlined to ensure precise evaluation of the ASIC performance. The novel readout ASICs are compared by assessing their maximum output count rate capabilities. Furthermore, we propose strategies to enhance the output count rate by preventing preamplifier saturation, providing insights into the challenges and methods for achieving high-flux rate BSE detection. Experimental verifications validate the effectiveness of the proposed strategies and assessment methodologies in achieving high detection accuracy.