Novel polymer multilayer CMOS compatible technology for multilevel microfludic devices

This work describes a novel fabrication process based on successive wafer level bonding and releasing steps, that allow us to stack several photopatterned SU-8 layers. Based on a low temperature bonding process, this work enhances it by the use of a Kaptontrade film as one of the substrates where the SU-8 is spun. The lack of adhesion between Kapton_TM and SU-8 offers the possibility to release the top substrate after the bonding and continue repeating the same steps to obtain multilayer stacks. Multilevel interconnected microfluidic channels with good sidewall profiles are achieved. In addition, the Kaptontrade releasing step leaves the fabricated structures in contact with the outside simplifying the packaging, which is described in this work