By Cameron Chai
Massachusetts Institute of Technology (MIT)’s multidisciplinary research group, the Center for Polymer Microfabrication is designing production processes for microfluidics from the scratch in order to mass produce microfluidic devices.
The Center for Polymer Microfabrication is designing processes for manufacturing microfluidic chips. Pictured here is a chip fabricated by the center's tailor-made production machines. (Credit: Photo: Melinda Hale)
David Hardt is the head of the research center funded by the Singapore-MIT Alliance. The center is studying the characteristics of polymers under plant conditions, developing advanced machines and tools to fabricate chips based on polymers at production levels, devising quality-control processes to monitor the integrity of a chip at submicron scales, and decreasing the production costs.
The research group concentrates on microembossing, an imprinting technique wherein a pattern of small channels is stamped subsequent to heating a polymer. During the tests, the team identified issues in the existing embossing technique. To stop embossing failures during a production setting, the team investigated the interactions and measured the mechanical forces between the embossing tool and the cooling polymer. Using these measurements, the team developed embossing tools specially designed to reduce polymer stickiness. These tools were able to fabricate chips precisely and rapidly at a lower cost, Hardt said.
Besides fabricating microfluidic devices, the research group is developing advanced quality-control techniques. Since microfluidic chips have small features, the process of checking the quality of every feature is time-consuming and can only be viewed under a high-resolution microscope. The research team developed a rapid and reliable method to assess the health of the production process of microfluidic chips by adding a small ‘X’ feature to the pattern of the chip, instead of checking whether all channels of a chip are imprinted. This ‘X’ feature is the most difficult of all to be embossed on a chip. Accurate embossing of the ‘X’ feature determines the quality measure of a chip’s production process.
The Center for Polymer Microfabrication is now seeking ways to engineer a ‘self-correcting factory’ that can test products automatically. Hardt envisages that the production process automatically adjusts the machine settings to rectify the process when the product malfunctions. The research group has designed algorithms to fine-tune the machines to rectify the production differences.