Cost-effective and reliable sealing method for PDMS (PolyDiMethylSiloxane)-based microfluidic devices with various substrates

A cost-effective and simply handling bonding method using siloxane-based adhesion promoter is introduced to increase the adhesion strength between cured PDMS and various substrates. The working mechanism of adhesion promoters is based on post-cure reaction in PDMS curing and they have similar chemistry compositions with PDMS prepolymers. It is experimentally investigated and proved that the adhesion strength of the resulted interface depends on –SiH group and Pt catalyst in adhesion promoters and molecular structures and polarity of substrates surfaces. By modifying their compositions uniform and perfect adhesion can be obtained for different substrates and meet different markets requirements, e.g., PDMS and glass which could be applied for biology, chemistry and solar cell fields, FR4 for electronics field and copper for electronics and thermal cooling fields, etc. Also, considering the quality and reliability requirements from potential application markets of microfluidic devices an environmental test procedure is summarized and according to the defined procedure, the environmental stability of realized PDMS-based microfluidic devices with different substrates has been tested with the result that they exhibited excellent stabilities and suitability for mass production.