Solution‐Processed Flexible Threshold Switch Devices

Abstract Flexible threshold switch devices are essential for low‐power and high‐speed semiconductor devices. Especially, bidirectional threshold switch has been regarded as the ideal switching device for ultrahigh‐density crosspoint memory devices. Here, a flexible Pt/Ag‐doped ZnO/Pt switch on the flexible plastic substrate synthesized by electrochemical bottom‐up deposition is introduced. The flexible switch has bidirectional threshold switching behavior with ultralow off‐current, high selectivity (≈10⁷), and super‐steep threshold slope. The bidirectional threshold switching behavior is related to migration of silver ions to form Ag filament. This device shows stable electrical properties, endures constant voltage stress, and retains good reliability under mechanical stress. It is believed that this study would open up new possibilities for high‐density flexible memory devices by introducing flexible novel bidirectional, high‐performance switching devices for emerging flexible electronics.