Exfoliated α-MoO3 Slab Patterning

Thin α-MoO₃ slabs were prepared by mechanically exfoliating bulk crystals^{45 (link)}. PoCs were fabricated in a large-area α-MoO₃ slab using a focused ion beam microscope (FEI Helios Nanolab 600) with an electron source that is capable of capturing high-resolution scanning electron microscopy images for device quality check right after patterning. A 28 pA patterning current (gallium ions) was selected with 30 kV accelerating voltage to minimize any potential damage to the functional areas in the α-MoO₃ slab with an optimized period of total milling time. Note that the PoCs were etched through α-MoO₃ slabs precisely to minimize overmilling and the redeposition effect by calibrating a test sample first.