A Study On The TSV Filter Design And Characteristic Analysis

As 5G technology continues to mature and become commercially available,ultra-fast network speeds and extremely short network delays have further promoted the development of driverless driving,artificial intelligence,and machine learning.The demand for high-frequency filters is further increased by 5G technology,so it is both an opportunity and a challenge for the development of filters.The traditional filter based on PCB technology cannot meet the future requirements because of its shortcomings such as large area,difficulty in integration and poor filtering effect at high frequency.At present,it is necessary to study new technologies that can make up for the shortcomings of traditional filters to a certain extent.The solution provided in this article is based on through-silicon via(TSV)filters.At first,TSV was a vertical interconnection in three-dimensional integrated circuits.As TSV technology and chip manufacture technology continued to merge,passive devices also began to use this technology.Capacitors,inductors and filters based on TSV have the advantages of small area,easy integration and good high frequency characteristics.This article proposes three TSV-based filters,including design,modeling,and characteristic analysis.First,low-pass filter(LPF)and high-pass filter(HPF)based on TSV are proposed.Using the constant K method to derive the lumped LPF and HPF(cut-off frequency 20GHz)component values,the LC circuit model is established.The spiral inductor based on the redistribution layer(RDL)and the capacitor based on the TSV array are designed,and then according to inductors and capacitors,build LC LPF and HPF based on TSV.Using ADS software and HFSS software to perform equivalent circuit model simulation and finite element method verification,the results show that the error of ADS and HFSS results is less than 2%,and the area of TSV LPF and HPF is only 1.085mm2 and 3.28mm2.At the same time,the quality factor and frequency characteristics of RDL spiral inductors and TSV array capacitors and the change curve of TSV LPF filtering characteristics with physical dimensions are studied.The difficulties in packaging and design attention of TSV LPF are further discussed.Then,using the same design method,two TSV-based band-pass filters(BPF)(bandwidths of 10 GHz,BPF1 center frequency of 20GHz,and BPF2 BPF1 center frequency of 20GHz,and BPF2 center frequency of 100GHz)are proposed.The results show that the TSV BPF1 finite element simulation results are in good agreement with the equivalent circuit model,but the TSV BPF2 finite element simulation results are very different from the equivalent circuit model results.This is because BPF structures of the same order are more complicated than LPF and HPF,and as the frequency increases,the minimum capacitance of BPF will be smaller.The parasitic capacitance of the interconnection accounts for 1.13%of the minimum capacitance of BPF1,and the parasitic capacitance of the interconnection accounts for 30%of the minimum capacitance of BPF2.Due to parasitic effects,TSV lumped filters cannot meet THz design requirements.In order to meet the design requirements of THz,a substrate integrated waveguide(SIW)filter based on TSV was proposed.The filter realized a center frequency of 3.1THz and a passband of 0.1THz and the S11 in the passband was not less than 10dB.The SIW BPF design makes up for the lack of TSV lumped BPF that cannot meet THz frequencies.In summary,with the requirements of filter miniaturization and integration this paper proposes an important solution of TSV-based filters,which realizes the miniaturization and integration of filter structures and provides theoretical support for the development of miniature RF systems and portable equipment.