Fabrication of a Piezoelectric ZnO/ZnMgO Coaxial Nanorod Force Sensor on Ti‐Wire for Intravascular Intervention Monitoring

Abstract The fabrication of force sensors is reported using ZnO/ZnMgO coaxial nanorod arrays grown on a titanium (Ti) wire and their application for force monitoring inside a blood vessel during catheterization procedures. The core‐shell nanorod arrays are grown using catalyst‐free metal–organic chemical vapor deposition (MOCVD), enabling precise control over the growth and morphology of the nanorod arrays. The ZnO/ZnMgO heterostructures grown on Ti‐wires are characterized using various techniques and confirmed for suitability for force sensing applications. The force sensor is fabricated by creating Schottky metal contacts at the nanorod tips, while an insulating polyimide layer fills the gaps between the nanorod arrays, electrically separating the top metal contact from the bottom Ti‐wire. The sensor's performance is evaluated under various force conditions using a voice coil motor with a soft polydimethylsiloxane (PDMS) pressure stamp to mimic the contact force between the sensor and the blood vessel. The sensor demonstrated high sensitivity, stable, and fast force responses under periodic applied forces. Furthermore, the force sensor is integrated with catheter for contact force monitoring inside an artificial blood vessel. The fabrication of force sensor on a Ti‐wire substrate creates a flexible, biocompatible sensing element suitable for implantation and real‐time force monitoring in vascular environment.