Due to the presence of paraffin patterns on one of the COC
wafers, polymer fusion bonding could not be used because of
the low melting temperature of paraffin (55–57 ◦C). Further, conventional
adhesive bonding by spin coating could not be used.
Thus, stamping was used to selectively deposit UV-cured adhesive
to the bonding surface of COC wafer and prevent contact
with the paraffin islands or channel structures.