UCLA researchers have developed a method to fabricate electrowetting microfluidic devices without assembly of their subcomponents.
Current microfluidic devices having a cavity configuration with multiple electrodes must have their components separately fabricated and subsequently assembled (e.g., bonded, clamped) in order to form a cavity. For example, fabrication of a "parallel-plate" electrowetting-on-dielectric (EWOD)-based device commonly involves photolithographic patterning of electrodes on one or both plates, followed by a coating of thin-film dielectric, manual alignment, and bonding of the plates using a spacer. The assembly step is not suitable for batch fabrication. Also, assembled devices require large tolerances in cavity dimensions leading to significant error in droplet volumes.
This invention enables scalable production of microfluidic devices without assembling the subcomponents. Also, the no-assembly process produces cavities of precise dimensions making it particularly suitable for designs requiring smaller fluid volumes (e.g., sub-nanoliter volumes) with high accuracy.
Researchers at UCLA have developed a method to fabricate microfluidic devices monolithically without assembly of subcomponents by using a surface micromachining process.
An EWOD-based digital microfluidic device has been experimentally validated by performing all core microfluidic droplet operations (i.e., creation, transport, division, and addition of droplets). The device has performed these core operations using aqueous droplets (~100 picoliters) in air and oil.
|United States Of America||Issued Patent||8,883,014||11/11/2014||2011-819|