A low-cost method of fabricating Parylene-SU-8 micro-nanofluidic chip by thermal nanoimprint and multilayer compositing

A new fabrication of micro-nano fluidic chips by thermal nanoimprint and multilayer compositing is proposed. The nano-channels with different aspect ratios were first manufactured by thermal nanoimprinting and Parylene layer coating, and the effect of parylene layer thickness on aspect ratio is studied. Then SU-8 layers with the micro channels and liquid reservoirs were superposed by ultraviolet exposure and secondary bonding to form a multilayer micro-nano fluidic chip. By optimizing the bonding parameters, a Parylene-SU-8 micro-nano fluidic chip with 200 μm wide and 8 μm deep micro-channels, cross-linked with 78 nm wide and 288 nm deep nano-channels was constructed, of which the maximum bonding strength is 0.92 MPa. This method has the advantages of simple process and low cost, which is suitable for mass manufacturing of micro-nano fluidic chips.