A Compact Design and Fabrication of Optical Force Sensors Based on Integrated GaN Devices

In this work, we have designed and fabricated a miniature optical force sensor based on integrated GaN devices. The GaN device consisting of light-emitting and light-detecting units is fabricated on a GaN-on-sapphire platform through wafer-scale microfabrication, and its optical and electrical properties are thoroughly investigated. The novel integration of patterned flexible film and a 3D printing post endows the device with force-sensing capabilities. The proposed sensor adopting a compact and elegant design enables operation without external optical components, making it suitable for a wide range of portable applications.