Microflotronics: A Flexible, Transparent, Pressure-Sensitive Microfluidic Film

There is an increasing demand for sensitive, flexible, and low-cost pressure sensing solutions for health monitoring, wearable sensing, robotic and prosthetic applications. Here, the first flexible and pressure-sensitive microfluidic film is reported, referred to as a microflotronic, with high transparency and seamless integratability with the state-of-the-art microelectronics. The microflotronic film represents the initial effort to utilize a continuous microfluidic layer as the sensing elements for large-area dynamic pressure mapping applications, and meanwhile an ultrahigh sensitivity of 0.45 kPa(-1) has been achieved in a compact, flexible, and transparent packaging. The response time of the device is in the millisecond range, which is at least an order of magnitude faster than that of its conventional flexible solid-state counterparts. In addition, the fabrication process of the device is fully compatible with the industrial-scale manufacturing of capacitive touchscreen devices and liquid-crystal displays. The overall device packaging can be as thin as 200 m with an optical transparency greater than 80%. Several practical applications were successfully demonstrated, including surface topology mapping and dynamic blood pressure monitoring. The microflotronic devices offer an alternative approach to the solid-state pressure sensors, by offering an unprecedented sensitivity and ultrafast response time in a completely transparent, flexible and adaptive platform.