In Situ Device‐Level TEM Characterization Based on Ultra‐Flexible Multilayer MoS₂ Micro‐Cantilever

Abstract Current state‐of‐the‐art in situ transmission electron microscopy (TEM) characterization technology has been capable of statically or dynamically nanorobotic manipulating specimens, affording abundant atom‐level material attributes. However, an insurmountable barrier between material attributes investigations and device‐level application explorations exists due to immature in situ TEM manufacturing technology and sufficient external coupled stimulus. These limitations seriously prevent the development of in situ device‐level TEM characterization. Herein, a representative in situ opto‐electromechanical TEM characterization platform is put forward by integrating an ultra‐flexible micro‐cantilever chip with optical, mechanical, and electrical coupling fields for the first time. On this platform, static and dynamic in situ device‐level TEM characterizations are implemented by utilizing molybdenum disulfide (MoS₂) nanoflake as channel material. E‐beam modulation behavior in MoS₂ transistors is demonstrated at ultra‐high e‐beam acceleration voltage (300 kV), stemming from inelastic scattering electron doping into MoS₂ nanoflakes. Moreover, in situ dynamic bending MoS₂ nanodevices without/with laser irradiation reveals asymmetric piezoresistive properties based on electromechanical effects and secondary enhanced photocurrent based on opto‐electromechanical coupling effects, accompanied by real‐time monitoring atom‐level characterization. This approach provides a step toward advanced in situ device‐level TEM characterization technology with excellent perception ability and inspires in situ TEM characterization with ultra‐sensitive force feedback and light sensing.