Microfluidics-based electronics have shown great potential in numerous applications, such as energy harvesters, bio-inspired devices, and wearable healthcare sensors. Fabrication challenges and material incompatibilities pose barriers to achieving the full potential of this emerging field. Elastomeric flexible microfluidic channels are conventionally fabricated by casting on a micro-machined mold, followed by a bonding step. Difficulty fabricating multilayers, and weak bonding to many substrates limit device capabilities and scalability. Integration of transducers within microfluidic channels is also challenging, especially for materials requiring high temperature annealing.
Novel processing techniques for the realization of scalable and flexible microfluidic electronics have been developed to suit a wide range of substrates. Biocompatible Polyethylene-glycol (PEG) is Inkjet-printed as a sacrificial layer. Elastomers, the channels’ structural material, are cast on PEG and cured. PEG can then be removed through heating above its phase-change temperature. This process allows easy modulation of the shape and dimensions of the channels on any substrate, and eliminates the need of manual realization of multilayers interconnection. Integration of ferroelectric and magnetic sensors is demonstrated with a photonic annealing process that enables film heating to over 900°C with insignificant substrate heating. Combined, these techniques enable realization of a new generation of wearable, flexible microfluidic electronics.
Traumatic brain Injury (TBI) has emerged as the signature injury of modern war, impacting over 300,000 Servicemembers since 2000. While 82% of these injuries are classified mild, there is significant concern with the potential for long-lasting neurocognitive and neuro degenerative effects. Diagnosis of mild TBI is difficult, with symptoms that are wide-ranging, non-specific, and often delayed in onset. The Blast Gauge® System was created to provide an objective measure of blast overpressure and acceleration exposure, providing triage data to assist in identifying soldiers at risk of TBI and detailed waveforms to enable correlation of singular and repetitive exposure to acute and chronic injury. From concept to deployment in 11 months and company formation to first product shipment in 4 months, this MEMS-based soldier-borne blast dosimeter has rapidly provided a new capability to track exposure in training and operations for the US DoD, law enforcement, and international militaries. Widespread deployment of the technology has yielded new insight into previously unrecognized dangers of heavy weapons training and captured valuable information about lED exposures in theater.