A Switched Flexible Dual-Mode Bandpass Filter Tuned by Organic Electrochemical Transistor

A frequency tunable flexible bandpass filter (BPF) based on electrical tuning of organic electrochemical transistors (OECTs) is designed and fabricated. Microstrip BPF is prepared by screen printing technology. OECTs are integrated on the flexible filter by means of spin coating and pouring. The center frequency of the BPF can be dynamically offset from 3.48 to 3.75 GHz at a bias voltage of 1.2 V. In addition, the consistency of bending and flatness tests demonstrates the high reliability of the proposed method and the application potential in the field of wireless communication and wearable devices.