A Si-based FPW sensor array system with polymer microfluidics integrated on a PCB

Many methods for fabricating structures for microfluidic-based sensors have been developed in recent years. However, little has been reported on effective methods for integrating these structures into electronic systems for analysis and fluidic delivery. This paper describes a straightforward and versatile fabrication platform for polymer microfluidics that readily accommodates integration with silicon-based sensors, printed circuit, and surface mount technologies. In particular, we have demonstrated a novel system for distributed fluid delivery to a flexural plate wave (FPW) chemical/biological sensor where micromachined fluidic components are combined in a single package with silicon die, multilayer printed circuit board, and surface mount electronics. In the same fabrication platform, we have demonstrated temperature control of the sensor with 0.1°C precision using integrated metal thin-film heater and sensor elements. This is an important capability for FPW sensors to compensate for temperature-induced drift. We present results for the on-board microfluidic system where the sensor is used to detect changes in the composition of the supplied fluid.