Supplementary Figure 1: Dimensioned scWB silicon wafer mold drawing.

Example wafer mold design for the scWB. The wafers are fabricated using standard photolithography techniques with SU-8 2025 photoresist. As SU-8 2025 is a negative photoresist, regions of the mask containing features to be polymerized (e.g. the micropillars) should be transparent. The photomasks are printed on mylar.