Post-hydrophilic treatment free plastic biochip fabrication method using polyurea film

A novel low temperature bonding method was developed by using polyurea film as intermediate layers. A microchip having microchannel which has highly hydrophilic surface was realized by the pretreatment of VUV (vacuum ultraviolet) light irradiation. The bonding temperature was low enough to use thermo plastic channel plates such as PMMA (poly-methyl methacrylate) with negligible deformation of the channel structure. The results of contact angle measurements indicate that the highly hydrophilic surface of the microchannel was kept after the bonding process. For actual micro biochip fabrication, the post-hydrophilic treatment after bonding process can be skipped.