In general, solvent bonding is a longer process than thermal fusion bonding, but it does not require high temperatures, which could potentially reduce the fabrication cost. In solvent bonding, overexposure of the substrates to the solvent can result in deformation of the microfluidic channels and solvent residue could adversely affect the functionality of immobilized biomolecules. Therefore, the exposure time and concentration of the solvent are important factors in this method.