Fig. 2

SEM images after a the RIE process, b 3 min of Au deposition, c 5 min of ion milling, and d 10 min of piranha cleaning. The bilayer polymer was imprinted by UV-NIL with a 400 nm square pattern. The thicknesses of the bending zone and undercut after RIE were around 53 and 17 nm, respectively. The insets represent 60°-tilted SEM images [48]