Solution-Processed Stretchable Ag2S Semiconductor Thin Films for Wearable Self-Powered Nonvolatile Memory

Abstract

Compared with the large plastic deformation observed in ductile metals and organic materials, inorganic semiconductors have limited plasticity (<0.2%) due to their intrinsic bonding characters, restricting their widespread applications in stretchable electronics. Herein, the solution-processed synthesis of ductile alpha-Ag2S thin films and fabrication of all-inorganic, self-powered, and stretchable memory devices, is reported. Molecular Ag2S complex solution is synthesized by chemical reduction of Ag2S powder, fabricating wafer-scale highly crystalline Ag2S thin films. The thin films show stretchability due to the intrinsic ductility, sustaining the structural integrity at a tensile strain of 14.9%. Moreover, the fabricated Ag2S-based resistive random access memory presents outstanding bipolar switching characteristics (I-on/I-off ratio of approximate to 10(5), operational endurance of 100 cycles, and retention time >10(6) s) as well as excellent mechanical stretchability (no degradation of properties up to stretchability of 52%). Meanwhile, the device is highly durable under diverse chemical environments and temperatures from -196 to 300 degrees C, especially maintaining the properties for 168 h in 85% relative humidity and 85 degrees C. A self-powered memory combined with motion sensors for use as a wearable healthcare monitoring system is demonstrated, offering the potential for designing high-performance wearable electronics that are usable in daily life in a real-world setting.