Research On The Characteristics Of TSV Inductors In The Case Of Multi-physics Coupling

Inductance is one of the most widely used passive devices in integrated circuits.Through-Silicon Via(TSV)technology is the key technology of Three-Dimensional Interagted Circuit(3D IC).It provides a new option to meet the actual needs of inductor design,namely TSV inductors.In the actual manufacturing and application process,the interaction between the force field,temperature field and electric field in the TSV inductor is a nonlinear coupling process.Simply considering the changes in stress,heat,and electricity separately will underestimate the negative impact,which can lead to serious reliability problems.Moreover,TSV inductors have a wide range of application fields and complex application environments.In order to ensure the reliability of TSV inductors,it is necessary to conduct collaborative research on its multi-physics coupling characteristics.The article focuses on TSV 3D spiral inductors and TSV 3D toroidal spiral inductors.The main content of the multi-physics problem of TSV inductors is as follows:1.The mismatch of the thermal expansion coefficients between the materials will cause thermal stress around the inductor.It will affect the electrical performance of the inductor.The ANSYS workbench simulation software is used to study the thermal-mechanical-electrical coupling characteristics of the inductor.The obtained electrical parameters are compared with the electrical parameters without considering the multi-physics coupling.The results show that the largest change is in the case of P-type silicon substrate,and the change rates of inductance and quality factor of TSV 3D spiral inductor are 18.87%and 8.27%,respectively;TSV 3D toroidal spiral inductor inductance value and quality factor change rate were 15.81%and 6.81%.In order to further improve the research efficiency and shorten the simulation time,a two-dimensional planar circuit is used to replace the three-dimensional model simulation.The TSV 3D spiral inductor was selected to construct the inductor equivalent circuit model,and the ADS software was used to conduct the physical field coupling study at the circuit level.The results showed that the error between the simulation results and the three-dimensional model was about 2%,which can replace the three-dimensional model for research.2.There is electrical and thermal coupling during the actual energization of the inductor,and the COMSOL Multiphysics simulation software is used to study the temperature distribution of the device,which is coupled with the force field.Completed the research on the electrical-thermal-mechanical coupling characteristics of TSV inductors.Finally,the influence results are characterized by comparing the electrical parameters,and the largest change is in the case of the P-type silicon substrate.The change rate of TSV 3D spiral inductor inductance value and quality factor are 14.13%and 5.91%,respectively.Considering the influence of the operating temperature on the inductance,the TSV 3D toroidal spiral inductor was selected to study the change of its electrical parameters with the change of the operating temperature.The article conducts an in-depth analysis of the multi-physics coupling model of TSV inductors.The research results are helpful for designers to predict its reliability in 3D IC,and play a very significant role in structural design optimization and design cost reduction.