Study On Stretchable Flexible Interconnect Circuit Model

With the development of Bio Medical and wearable electronic devices,stretchable flexible electronic devices have become the focus of current research.At present,the research of stretchable flexible electronic mainly focuses on its preparation process and structure.The study of its electrical properties is rather weak.The research of stretchable flexible interconnect is still blank.Therefore,the research of scalable flexible interconnect circuit model is very important.In this thesis,the deformation characteristics and electrical properties of stretchable flexible serpentine wires are simulated by ANSYS and HFSS and verified by experiments.A circuit model suitable for stretchable flexible interconnection is built on the basis of traditional interconnection.The main research results are as follows:?1?Through the study of deformation characteristics,with the increase of deformation displacement,the phenomenon of stress concentration occurs at the top of the arc in the snake structure and the stress increases with the increase of deformation.At the same time,the warping deformation in the Z direction is generated and with the increase of the shape variables,warping deformation begins to spread from the top of the arc to the two sides.As a result,the points where the wires are most likely to fall or break during tension are the points of stress concentration.Therefore,the maximum elongation factor of snake wire is the maximum tensile rate at the top of the arc.The electrical parameters of the wires under different deformation are simulated by HFSS.With the increase of the shape variables,the most obvious parameters are parasitic inductance and coupling capacitance and the maximum growth rates are 25.42%and 36.55%respectively.The parasitic resistance of the interconnection wire is only slightly increased,and the maximum growth rate is 2.76%.With the increase of deformation displacement,the transmission characteristic parameter S₁₁ of the wire becomes larger,while the S₂₁ parameter becomes smaller.?2?The experimental results show that the transmission characteristics of the wire gradually change with the increase of the shape variables.The measured wire transmission performance is worse than the simulation result.The main reason is that the substrate is a flexible material,so when the probes insert and the contact is not uniform,resulting in the local virtual touch,and wire surface oxidation occurs,resulting in poor performance of wire transmission.The trends of simulation and experimental measurements are consistent.With the increase of deformation,the S₁₁ parameter of wire becomes larger,and the S₂₁ parameter becomes smaller.?3?The geometric model of V type wire and RLCM model suitable for stretchable flexible interconnect are established basis of RLC model of traditional interconnect circuit.When establishing the geometric model of V type conductor,it is found that the angle and shape variables of V type wire conform to the cosine law,and the thickness of the flexible dielectric layer is approximately linear with the shape variable.In the simulation research of HFSS,it is found that the inductance parameter varies with deformation obviously.Therefore,the mutual inductance factor M which represents the deformation is introduced when the analytical model is established.The RLCM two ports circuit model is established by ADS.The transmission characteristic parameters S₁₁ and S₂₁ are simulated.Compare the S parameters of the wire with HFSS.It is found that the maximum deviation of S₁₁ parameters is 0.0928dB and the maximum deviation of S₂₁ parameters is 0.0003dB.Thus,the correctness of the RLCM model is verified.Based on the study of the deformation characteristics and the circuit model of the stretchable flexible interconnect,the deformation characteristics and electrical properties are combined well.The stretchable flexible interconnect is an important part of stretchable flexible system.Through this thesis,we have mastered the change rule of the stretchable flexible interconnect,to provide theoretical support and help for the further research on stretchable flexible electronic system.