Fig. 8From: Highly sensitive ultrasound detection using nanofabricated polymer micro-ring resonators(Reproduced with permission from [34])Nanofabrication of polymer MRRs by sNIL. a A schematic illustration of fabrication procedures of sNIL. SEM images of the Si hard mold (b), the PDMS soft mold (d), and the PS MRR (f) by sNIL. Scale bar 20 μm. Their corresponding magnified SEM images for the coupling region are shown as (c), (e), and (g). Scale bar 2 μmBack to article page