A Dynamic Precision Measurement Method For Flexible Devices Made Of Two-Dimensional Materials

Flexible electronic devices have sparked extensive research interest and achieved significant applications worldwide,such as flexible circuits,displays,and energy storage devices.With the emergence of two-dimensional nanomaterials and their heterostructures,the continued miniaturization of device dimensions has become an important trend in flexible electronics research.However,as device size continues to decrease,many challenges in fabrication,testing,and analysis have become increasingly prominent in the field of flexible devices.The most critical challenge is accurately measuring the dynamic response of these miniaturized electronic devices.Specifically,as the size of flexible electronic devices continues to shrink,it becomes increasingly difficult to distinguish the external response of electrical contacts/wires from the mechanical modulation of the device’s inherent response.Based on this,this thesis presents a new connection scheme that can effectively isolate and suppress external signal interference that does not belong to the device’s own response.This thesis uses a self-designed novel wiring structure,which closely"floats"above the device on a platform and moves synchronously with the flexible device to effectively minimize the mechanical deformation of connecting wires,greatly reducing crosstalk of the wire deformation response on the device’s intrinsic signal.Furthermore,this thesis uses finite element methods to simulate the strain of the wires under different connection schemes and theoretically analyze the influence of substrate bending on the wires.The thesis prepares graphene thin film materials using mechanical exfoliation and transfers them onto a PET flexible substrate using dry transfer methods to prepare a flexible pressure sensor based on graphene.Dynamic electrical tests of the sensor are then conducted using different wire connection schemes.Comparative studies clearly observe the complex mechanical response of electrical contact points in traditional connection schemes;this hinders the accurate testing of the device’s inherent response.The self-designed new connection scheme is proven to be highly efficient and reliable in suppressing external interference,and can improve the dynamic measurement accuracy of the device by several orders of magnitude.In addition,this thesis uses a self-designed new connection scheme to systematically test the flexible electrical properties of graphene and molybdenum disulfide（MoS₂）.Based on the successful fabrication of a flexible field-effect transistor based on MoS₂,changes in the device’s electrical properties during dynamic bending are further studied,and optimization schemes for performance improvement are proposed from the perspectives of structure design and fabrication methods.