Fabrication of Tri-Axial MEMS Tactile Sensor for Minimally Invasive Medical Application using Wafer-Level Packaging

In this study, we successfully fabricated a minimum triaxial MEMS tactile sensor with a diameter of 320 µm for a medical catheter. The miniaturized sensor is expected to be installed onto the tip of the minimum guidewire to ensure a tactile sensor can be obtained to avoid an accident of breaking through blood vessel walls. After fabricating the detection unit and through-silicon via (TSV) unit, the two units were bonded using wafer-level gold-gold surface-activated bonding followed by clipping of the tactile sensor with a diameter of 320 µm. We confirmed that the proposed and optimized fabrication process realized an ultrasmall tactile sensor that can detect triaxial forces, which can be used in an advanced catheter system with a tactile-sensitive guidewire.