Fabrication and packaging technologies of Love-wave-based microbalance for fluid analysis

Sensors able to operate with liquid phases are the key-point for the development of biochemical lab-on-chip devices. In this work, we present the design and manufacture of Love-wave sensors equipped with a liquid cell, at the wafer scale level, to allow operation with liquid media. Love-wave sensors are fabricated on AT-cut quartz plates (IEEE Std-176 notation (YXlt)/36/90) and passivated by a 2.5 μm thick silica overlay. The fabrication process using the celebrated SU-8 epoxy-based photoresist combined with silicon or quartz machined covers is presented, revealing robust enough for ensuring a reproducible sensor fabrication and packaging. Results are reported emphasizing the efficiency of the proposed approach.