Bonding-friendly pcPDMS: Depositing Parylene C into PDMS matrix at an elevated temperature

This paper reported a simple and effective process of bonding-friendly Parylene C-caulked PDMS (pcPDMS) for low-permeability required microfluidics. Parylene C was deposited into PDMS matrix at an elevated temperature (higher than 135°C) to caulk the permeable sites. The so-prepared pcPDMS can be directly bonded with oxygen plasma treatment just as pristine PDMS. SEM EDAX and Laser scanning confocal microscopy (LSCM) were introduced to characterize the Parylene C caulked status in the PDMS matrix based on the specific Cl element component and the firstly-found temperature-sensitive autofluorescence of Parylene C. The preliminary results indicated that the present bonding-friendly pcPDMS can successfully suppress the diffusion of small molecules into the PDMS matrix.