Figure 2.

Physical characterization of frame-supported membranes. A) Water-facilitated release of a free-standing membrane with SU-8 support (scale bar=1 cm). B) Pore size fidelity (measured diameter divided by mask diameter) in fabricated membranes. Ideal pore size fidelity was generally observed in all samples. C) Top view and D) 60° tilted representative SEM images of a UPP membrane with 3 μm pore size and 300 nm thickness. White arrows demonstrate the ultrathin thickness of the membrane (~300 nm) (scale bar=10 & 4 μm, respectively).