Study On Eletronmagnetic Characteristics Of Novel Interconnects And Power Distribution Networks(PDNs) For Three-dimentional Integrated Circuits(3D-ICs)

With the development of semiconductor industry,traditional integrated circuits face many serious challenges.As the chip is being scaled down,the sizes of CMOS transistors and interconnects are approaching their physical limits.Moreover,the delay,crosstalk and power consumption of interconnects become very serious with the operating frequency increasing.In order to solve these problems,three-dimensional(3-D)integration technology based on through-silicon via(TSV)has been born at the right moment.Although TSV can significantly reduce the power consumption,improve the integration and transmission rate of signals or power,it meets some new problems,such as signal integrity,power supply,and reliability ones.In order to improve the performance of TSV,the traditional interconnection technology has been improved in three aspects of substrate,insulator and filled part,respectively.Therefore,how to design new-type interconnects and power distribution network(PDN)to ensure their high performance,is the main target of this thesis.The main research work and academic contribution of this dissertation is summarized as follows.(1)Considering the MOS,skin and temperature effects,an equivalent circuit model of TSV array is built.Compared with the commercial software HFSS,the model is proved to be suitable for uniformly distributed TSV array with multi-ground TSVs up to 100 GHz.Then,the impacts of physical and material parameters on the electrical properties of TSVs are studied in detail.(2)To evaluate electro-thermo-mechanical characteristics of TSV array and channel with DC voltage and transient electromagnetic pulse(EMP)applied,hybrid time-domain finite-element method(TD-FEM)is adopted to co-solve current continuity,heat conduction and thermal stress equations,where the temperature-dependent material parameters are treated appropriately.Further,our algorithm is integrated into large scale parallel infrastructure(JAUMIN)developed by the Beijing Institute of Applied physics and Computational Mathematics,for fast simulating multiphysics coupling characteristics of large scale TSV channels.(3)The electrical properties of through glass vias(TGV)and polymer-liner TSVs are characterized and compared with conventional TSVs up to 100 GHz,with the improved equivalent circuit model of TSV array.Further,the influence of thickness of polymer liner is considered.(4)Using the in-house developed multiphysics fields coupling algorithm based on hybrid TD-FEM,the electro-thermo-mechanical responses of TGVs,polymer-liner TSVs and polymer-filled TSVs with DC voltage and periodic EMP applied are captured and studied in detail.In particular,the impacts of physical parameters(i.e.the thickness of polymer liner,the diameter of the filled polymer,the width of horizontal interconnects,etc.)on the reliability of these interconnects are examined.(5)The equivalent circuit model of carbon nanotube(CNT)TSV array is constructed with an extra contact resistance taken into account.Also,the impacts of CNT kinetic inductance,diameter,filling ratio and temperature on the effective complex conductivity and electrical properties are analyzed in detail.Moreover,combining CNT-TSV array with on-chip PDN,the circuit model of multi-stacked PDN is built.Further,the impacts of CNT physical parameters,the number of stacking layers and TSVs on the impedance characteristics of multi-stacked PDN are investigated comprehensively.