A Novel and Robust Packaging Technology for Miniaturized FET-Based Biosensors with Microfluidic Channels

Abstract

FET devices are extensively used for sensors, including gas sensors and biosensors. In contrast to traditional resistive devices, FET has transconductance gain, which can significantly improve the S/N ratio. Recently, more applications in biosensors combine microfluidic channels and FET system. In FET-based biosensors, the wafer manufacturing process always requires a lot of cost, and it is used for metal lines as interconnects. Miniaturized chip plays a key role in reducing the manufacturing cost. However, simultaneously integrating the sensor and microfluidic channels on one chip is challenging. In this study, a novel and robust packaging method has been developed, to effectively reduce the size of the sensor chip and thereby the cost. 1 mm2 FET sensor chip has been fabricated and embedded in epoxy. Photolithography and metal deposition were done followed by lift-off process for metal interconnect. The FET-embedded chip was passivated and covered by the microfluidic channel made of PMMA.