Microfluidic material for wafer-scale lab-on-chip production

November 04, 2013 // By EDN
Imec, the Belgium-based nanoelectronics research centre and JSR, a Japanese materials company, have used JSR’s PA (Photo-patternable Adhesive) material for wafer-scale processing of lab-on-chip devices. With PA as a key enabling material, imec has processed microfluidic cell-sorter devices, merging microheaters and sensors with wafer-scale polymer microfluidics. PA has the characteristics of good microfluidic channel material and an adhesive, at the same time, suitable for wafer-scale processes and mass production.

Lab-on-chip technology is expected to advance medical technology with powerful point-of-care diagnosis and treatment through on-chip molecular synthesis, separation, sensing, and detection. Key will be the ability to integrate microfluidics with heterogeneous components such as electronics, sensors, microheaters, and photonics in a cost-effective manner. To merge these elements successfully, new bonding and surface treatment materials are needed.

“PA solves a number of issues that we have with other materials, such as the widely-used PDMS (polydimethylsiloxane, a silicon-based organic polymer)”, says Liesbet Lagae, imec R&D manager of life science technologies. It has all the characteristics we are looking for in a photopatternable material to create microfluidic channels on silicon wafers, including a good channel definition and biocompatibility. But at the same time, it is an adhesive that allows direct thermal bonding with the cover glass. And unlike PDMS, it allows for wafer-scale processing, which is a prerequisite for industrial mass production.”

Imec used PA to process the next generation of its cell sorter lab-on-chip. Integrating on-chip imaging, in-flow cell tomography to identify cells, and bubble jet-flow technology to guide and sort individual cells, the prototype lab-on-chip can process up to 2,000 cells per second. One application envisaged for these ultrafast cell-sorters is the detection of circulating tumor cells in human blood.

Imec, www.imec.be