Electron-beam based nanoprobing for defect analysis of nanoelectronics

The rapid growth of digital applications and data processing, especially with the rise of artificial intelligence (AI), is driving an exponential increase in computing power needs. To manage this sustainably, high-performance semiconductor technology is required. To help realizing this, Imec has drawn a roadmap that will take the semiconductor industry to the 2 ångström (0.2 nm) node by 2036. In this roadmap, fundamental changes in chip architectures, materials, and transistor structures are proposed, including the stacking  n- and p-type transistors on top of each other in complementary FET circuits with a metal pitch of 16-12 nm, and incorporation of atomically thin 2D materials such as tungsten disulfide.

To facilitate the transition into the angstrom era, new failure analysis (FA) solutions must be developed, as detecting and visualizing defects in these devices will become increasingly more difficult. The FA community currently lacks clarity on how to achieve this efficiently and has identified several concerns. Nonetheless, it is evident that scanning electron microscope (SEM) based techniques, combined with in-situ electrical nanoprobing, configured in a so called nanoprober, will play a crucial role in this development due to their capability to enable analysis with sub-nanometer imaging resolution. A nanoprober utilizes ultra-sharp (≤5 nm) conductive probe tips that can be positioned with sub-nanometer accuracy, enabling precise characterization of individual transistors and interconnect structures.

This project aims to tackle several critical challenges associated with nanoprobing, including investigating the effects of electron beam irradiation on device characteristics and the complexities involved in probing individual transistors with backside power delivery. The research will focus on developing innovative solutions to these challenges, while also advancing the capability to isolate defects at the scale of individual nanosheets, nanowires, or transistors within a CFET configuration. Additionally, the PhD research will explore new methodologies by integrating electrical nanoprobing with atomic force microscopy (AFM)-based nanoprobing inside a SEM. This combined approach is expected to enhance the precision and scope of defect characterization and localization, enabling more detailed and accurate analysis of advanced semiconductor devices.