A SU-8-based compact implantable wireless pressure sensor for intraocular pressure sensing application.

Telemetric sensing has received a great deal of attention in noncontact human disease detection. To take advantage of this method, this paper presents a SU-8-based compact (1.52 mm × 3.23 mm × 0.2 mm) passive wireless pressure sensor, especially designed to measure the intraocular pressure. The sensor was microfabricated using biocompatible materials such as gold and SU-8 [1] to form the LC parallel circuit and the pressure sensitive diaphragm. The surface of the sensor is fully covered by SU-8, which isolates the working circuit from the biological tissue medium. The pressure signal can be detected by an external readout coil with up to 6 mm distance from the implanted sensor. The pressure sensitivity of the sensor was characterized in both air and saline environment. The microfabricated sensor has high sensitivity (>7,000 ppm/mmHg).