  Aberration-corrected scanning transmission electron microscopy (STEM) is
widely used for atomic-level imaging of materials. To accelerate the discovery
of new materials based on atomic-level investigations, the throughput of
aberration-corrected STEM experiments becomes more and more important. However,
the throughput of the full workflow of aberration-corrected STEM is still quite
low. A fundamental problem is that the preparation of high-quality thin STEM
samples (lamellae) depends on manual operation. Here, inspired by the recent
successes of "robot scientists", we demonstrate robotic fabrication of
high-quality lamellae by focused-ion-beam (FIB) with full automation software.
First, we show that robotic FIB can prepare lamellae with a high success rate,
where the robotic FIB controls rough-milling, lift-out, and final-thinning
processes. Then, we optimize the FIB parameters of the final-thinning process
for single crystal Si. Aberration-corrected STEM imaging of these Si lamellae
shows atomic-level images with 55 pm resolution. We also demonstrate robotic
fabrication of high-quality lamellae of SrTiO3 and sapphire. The robotic FIB
system will resolve the current bottleneck of the full workflow of
aberration-corrected STEM analysis and accelerate materials discovery based on
atomic-level imaging.
