Development of customizable soft and wearable electronics based on thermoforming

Abstract

There are numerous emerging soft and wearable electronics technologies that can measure various essential information of human. Amongst properties of soft and wearable electronics, customizability is becoming an important key factor towards state-of-the art wearable electronics owing to the increasing demands for industry 4.0 that satisfy the user’s diverse design needs such as robotics, virtual reality, and health monitoring. Therefore, we present a thermoforming based three-dimensional (3D) electronics: 3D-structured electronics and 3D-shaped electronics. Firstly, we present a fabrication method of customizable tactile sensor based thermoformed 3D-structured electronics. Thermoforming process transforms patterned 2D film-based electronics to elastically deformable 3D-structured electronics, which have a planar top surface with supporting legs. The 3D-structured electronics have high modulus tunability and high mechanical properties (negligible hysteresis, high creep resistance). These unique properties can be utilized to high-performance and customizable tactile sensor. Secondly, we present a fabrication method of 3D-shaped electronics based on pre-distorted pattern generation and thermoforming. Through this method, custom-designed 3D-shaped electronics is fabricated through the thermoforming process. The fabricated 3D-shaped electronics has high 3D conformability because the thermoforming process enables the complete replication of both the overall shape and the surface texture of the 3D mold. Furthermore, the usage of thermoplastic elastomer and a liquid metal-based conductive electrode allows for high thermoformability during the device fabrication as well as high stretchability during the device operation.