Solvent assisted bonding of polymethylmethacrylate: Characterization using the response surface methodology

This work presents the investigation of a novel solvent assisted bonding process developed for the fabrication of closed microchannels made from polymethylmethacrylate (PMMA). The effects of four process parameters on the deformation and the bond strength of the microchannel have been investigated using the response surface methodology (RSM). High bond strengths (3.5 ± 0.8 MPa) at low deformations (1.6 ± 0.3%) have been achieved at the center point of the design of experiment. The limits of the developed bonding process have been investigated by the fabrication of microchannels with low aspect ratios. Microchannels with a width of 130 μm and a depth of 4 μm have been fabricated. This is equivalent to an aspect ratio of 0.03. Further, the integration of the bonding process into the fabrication process of the wireless implantable strain sensor (WIPSS) has been verified and excellent bonding of the microchannel has been confirmed by ultrasound measurements.