Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8277047
Yarui Peng, D. Petranovic, S. Lim
In fan-out wafer-level-packaging, the package interconnection layers are fabricated similar to the back-end-of-line interconnect stack where multiple dies are tightly integrated with dense package routing for higher performance and lower power. However, electrical and magnetic field interactions may introduce significant uncertainties in system power and performance. For the first time, we provide two CAD flows for extracting coupling capacitance between the die and package. In particular, we first analyse the E-field interactions using field solvers and demonstrate their impacts on die-to-package coupling. We then propose a holistic extraction flow which integrates all layers from the chip and package and extracts all coupling elements for the maximum accuracy. We also propose an in-context extraction flow for chip designers, which only includes necessary regions of the redistribution layer and still captures the E-field impact from the package. Our in-context extraction requires less computing resources, allows heterogeneous integration, and is still highly accurate compared with the holistic extraction. Final, we demonstrate our flow using detailed package and multi-chip layout.
{"title":"Die-to-package coupling extraction for fan-out wafer-level-packaging","authors":"Yarui Peng, D. Petranovic, S. Lim","doi":"10.1109/EDAPS.2017.8277047","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8277047","url":null,"abstract":"In fan-out wafer-level-packaging, the package interconnection layers are fabricated similar to the back-end-of-line interconnect stack where multiple dies are tightly integrated with dense package routing for higher performance and lower power. However, electrical and magnetic field interactions may introduce significant uncertainties in system power and performance. For the first time, we provide two CAD flows for extracting coupling capacitance between the die and package. In particular, we first analyse the E-field interactions using field solvers and demonstrate their impacts on die-to-package coupling. We then propose a holistic extraction flow which integrates all layers from the chip and package and extracts all coupling elements for the maximum accuracy. We also propose an in-context extraction flow for chip designers, which only includes necessary regions of the redistribution layer and still captures the E-field impact from the package. Our in-context extraction requires less computing resources, allows heterogeneous integration, and is still highly accurate compared with the holistic extraction. Final, we demonstrate our flow using detailed package and multi-chip layout.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116576475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8276970
Chaofeng Li, Huapeng Zhao, Z. Chen, Jun Hu
The reconstruction of sparse radiation sources above a finite ground plane is important for the equivalent modeling of radiators such as slot antennas, printed circuit boards and slotted shields. Existing methods usually assume the infinitely large ground plane which is not realistically realizable and the results are not practically accurate since they ignore the edge diffraction effect of a realistic ground plane. In this paper, a finite ground plane is considered and its edge diffraction effect is modeled by the uniform theory of diffraction (UTD). A matrix equation relating sources with near fields is derived with the UTD and the half space Green's function approach. By solving the matrix equation, the radiation sources can be reconstructed from the near fields. In order to improve the efficiency and accuracy, the sparse source reconstruction is developed to solve the matrix equation. Different from existing methods, the proposed method considers the edge diffraction effect and applies the sparseness of the sources when solving the inverse problem. Therefore, it is more efficient and accurate than existing methods. Numerical results are presented to validate the effectiveness of the proposed method.
{"title":"Reconstruction of sparse radiation sources above a finite ground plane","authors":"Chaofeng Li, Huapeng Zhao, Z. Chen, Jun Hu","doi":"10.1109/EDAPS.2017.8276970","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8276970","url":null,"abstract":"The reconstruction of sparse radiation sources above a finite ground plane is important for the equivalent modeling of radiators such as slot antennas, printed circuit boards and slotted shields. Existing methods usually assume the infinitely large ground plane which is not realistically realizable and the results are not practically accurate since they ignore the edge diffraction effect of a realistic ground plane. In this paper, a finite ground plane is considered and its edge diffraction effect is modeled by the uniform theory of diffraction (UTD). A matrix equation relating sources with near fields is derived with the UTD and the half space Green's function approach. By solving the matrix equation, the radiation sources can be reconstructed from the near fields. In order to improve the efficiency and accuracy, the sparse source reconstruction is developed to solve the matrix equation. Different from existing methods, the proposed method considers the edge diffraction effect and applies the sparseness of the sources when solving the inverse problem. Therefore, it is more efficient and accurate than existing methods. Numerical results are presented to validate the effectiveness of the proposed method.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129033050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8277000
Na Li, J. Mao, Wensheng Zhao, M. Tang, W. Yin
In this paper, the electrothermal characteristics of a two-chip power delivery network (PDN) structure is investigated by using a frequency-domain co-simulation solver. The solver is developed based on finite element method (FEM) by circularly solving the wave equation for a full-wave electromagnetic analysis and the heat conduction function for the thermal analysis. A bandstop filter is used as an example to verify the accuracy and efficiency of the programs. Then the effect of metal and dielectric losses on the electrothermal characteristics of the PDN is emphatically studied. The electric field and temperature profiles on the resonance frequency are given out.
{"title":"Electrothermal co-simulation of a two-chip power delivery network in frequency domain","authors":"Na Li, J. Mao, Wensheng Zhao, M. Tang, W. Yin","doi":"10.1109/EDAPS.2017.8277000","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8277000","url":null,"abstract":"In this paper, the electrothermal characteristics of a two-chip power delivery network (PDN) structure is investigated by using a frequency-domain co-simulation solver. The solver is developed based on finite element method (FEM) by circularly solving the wave equation for a full-wave electromagnetic analysis and the heat conduction function for the thermal analysis. A bandstop filter is used as an example to verify the accuracy and efficiency of the programs. Then the effect of metal and dielectric losses on the electrothermal characteristics of the PDN is emphatically studied. The electric field and temperature profiles on the resonance frequency are given out.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129295697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8276966
Xinglong Wu, F. Grassi, S. Pignari, P. Manfredi, D. Vande Ginste
In this work, the mechanism of differential-to-common-mode (CM) conversion arising in differential interconnects due to bend discontinuities is investigated. A circuit interpretation of the phenomenon is provided in terms of lumped sources of interference included into the equivalent CM circuit. The obtained circuit model, assessed through full-wave simulation, allows inferring analogies and differences with respect to other sources of CM generation such as asymmetries and non-uniformities of the line cross-section, possibly occurring due to the manufacturing process. It is shown that the bent section can be interpreted as a local perturbation of an ideally uniform and symmetric microstrip cross-section and, as such, included into a more general simulation framework based on a perturbative approach aimed at the CM prediction in differential interconnects.
{"title":"Circuit interpretation and perturbative analysis of differential-to-common mode conversion due to bend discontinuities","authors":"Xinglong Wu, F. Grassi, S. Pignari, P. Manfredi, D. Vande Ginste","doi":"10.1109/EDAPS.2017.8276966","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8276966","url":null,"abstract":"In this work, the mechanism of differential-to-common-mode (CM) conversion arising in differential interconnects due to bend discontinuities is investigated. A circuit interpretation of the phenomenon is provided in terms of lumped sources of interference included into the equivalent CM circuit. The obtained circuit model, assessed through full-wave simulation, allows inferring analogies and differences with respect to other sources of CM generation such as asymmetries and non-uniformities of the line cross-section, possibly occurring due to the manufacturing process. It is shown that the bent section can be interpreted as a local perturbation of an ideally uniform and symmetric microstrip cross-section and, as such, included into a more general simulation framework based on a perturbative approach aimed at the CM prediction in differential interconnects.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121277081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8277059
Jingyi Du, Jinbao Guo, Dandan Xu, Qiong Huang
As the development of economic and technology, Internet of Things (IOT) has become an important part of strategic emerging industries, this paper takes into account, small equipment, large coverage area, network data security, low power consumption and so on, A remote monitoring system of temperature and humidity based on OneNet cloud service platform is proposed. The STM32F103RCT6 of ARM Cortex-M3 kernel is adopted as the main controller, SIM800C communication module based on authorized frequency band GSM/GPRS cellular communication technology is used, Combining digital temperature and humidity sensor SHT20, real-time and accurate data acquisition is achieved. At the same time, data is uploaded to the Internet of things OneNet cloud service platform through the EDP protocol. Equipped with WEB services and terminals APP can look at temperature, humidity and power voltage data at anytime, anywhere on the computer, mobile phones and other mobile devices. In order to make users obtain the threshold data information in time, the development adds the trigger function in the cloud server, it makes the product more convenient and intelligent.
{"title":"A remote monitoring system of temperature and humidity based on OneNet cloud service platform","authors":"Jingyi Du, Jinbao Guo, Dandan Xu, Qiong Huang","doi":"10.1109/EDAPS.2017.8277059","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8277059","url":null,"abstract":"As the development of economic and technology, Internet of Things (IOT) has become an important part of strategic emerging industries, this paper takes into account, small equipment, large coverage area, network data security, low power consumption and so on, A remote monitoring system of temperature and humidity based on OneNet cloud service platform is proposed. The STM32F103RCT6 of ARM Cortex-M3 kernel is adopted as the main controller, SIM800C communication module based on authorized frequency band GSM/GPRS cellular communication technology is used, Combining digital temperature and humidity sensor SHT20, real-time and accurate data acquisition is achieved. At the same time, data is uploaded to the Internet of things OneNet cloud service platform through the EDP protocol. Equipped with WEB services and terminals APP can look at temperature, humidity and power voltage data at anytime, anywhere on the computer, mobile phones and other mobile devices. In order to make users obtain the threshold data information in time, the development adds the trigger function in the cloud server, it makes the product more convenient and intelligent.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121616248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8276936
Wen-Wu Ruan, Cheng-rui Zhang, Liang Zhou, J. Mao
This paper established a general heat model of a multi-layer packaging. By using analytical solutions based on Fourier series, we were able to capture the temperature distributions of a realistic packages. We then fabricated photosensitive BCB based power MMICs packages and tested the temperature distributions. The fabrication process are given in detail. we were able to accurately calculate the temperature distributions of the power MMICs packages. Calculated, simulated and measured results show close correlations. This research will be useful in thermal management for further 3 dimensional packaging.
{"title":"Analytical solutions of temperature distributions based on fourier series for wafer level heterogeneous integrations","authors":"Wen-Wu Ruan, Cheng-rui Zhang, Liang Zhou, J. Mao","doi":"10.1109/EDAPS.2017.8276936","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8276936","url":null,"abstract":"This paper established a general heat model of a multi-layer packaging. By using analytical solutions based on Fourier series, we were able to capture the temperature distributions of a realistic packages. We then fabricated photosensitive BCB based power MMICs packages and tested the temperature distributions. The fabrication process are given in detail. we were able to accurately calculate the temperature distributions of the power MMICs packages. Calculated, simulated and measured results show close correlations. This research will be useful in thermal management for further 3 dimensional packaging.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121735104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8276948
Shuman Mao, Yuehang Xu, Xi Chen, R. Xu, Yongbo Chen, Nengwu Gao
This paper presents the investigation on the influence brought by trapping effects and gate leakage current in GaN HEMTs on the large signal performance as well as the DC characteristics. Kink effect is also taken into consideration in our model. The bias dependent threshold voltage Vds-kink has been studied. Results show that the leakage current will have a great effect on the DC performance while the trapping effects are the opposite case. In terms of large signal performance, the effects brought by gate leakage current will be distinct only when the input power is relatively high while the ones brought by substrate trapping is obvious regardless of the value of input power.
{"title":"Trapping and gate leakage currents effects in large signal modeling of microwave GaN HEMTs","authors":"Shuman Mao, Yuehang Xu, Xi Chen, R. Xu, Yongbo Chen, Nengwu Gao","doi":"10.1109/EDAPS.2017.8276948","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8276948","url":null,"abstract":"This paper presents the investigation on the influence brought by trapping effects and gate leakage current in GaN HEMTs on the large signal performance as well as the DC characteristics. Kink effect is also taken into consideration in our model. The bias dependent threshold voltage Vds-kink has been studied. Results show that the leakage current will have a great effect on the DC performance while the trapping effects are the opposite case. In terms of large signal performance, the effects brought by gate leakage current will be distinct only when the input power is relatively high while the ones brought by substrate trapping is obvious regardless of the value of input power.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126227100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8277015
Cheng-Yi Tian, Peng Wang, Yan Shi
In this proceeding, we propose a hybrid solver to model the electromagnetic-circuit problem. The EM subsystem is modeled by wave equation-based discontinuous Galerkin time domain (DGTD-WE) method while the circuit subsystem is computed with a SPICE-like circuit solver. Besides, a stable and general impedance transmission boundary condition (ITBC) is developed to couple the EM and circuit subsystems. Numerical example is presented to demonstrate the validity of the proposed method.
{"title":"Modeling hybrid EM-circuit system with wave equation-based discontinuous Galerkin time domain method","authors":"Cheng-Yi Tian, Peng Wang, Yan Shi","doi":"10.1109/EDAPS.2017.8277015","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8277015","url":null,"abstract":"In this proceeding, we propose a hybrid solver to model the electromagnetic-circuit problem. The EM subsystem is modeled by wave equation-based discontinuous Galerkin time domain (DGTD-WE) method while the circuit subsystem is computed with a SPICE-like circuit solver. Besides, a stable and general impedance transmission boundary condition (ITBC) is developed to couple the EM and circuit subsystems. Numerical example is presented to demonstrate the validity of the proposed method.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131063816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8276926
Yunqiu Wu, Shili Cong, Chenxi Zhao, Huihua Liu, K. Kang
A multi-bias transistor model is proposed in this paper. The nonlinear drain-source current, the output resistance, and the intrinsic capacitance are fully considered to characterize the transistor's bias-dependent performance. On this basis, the values of the model elements are extracted under different bias conditions. Furthermore, a 90 nm CMOS transistor is fabricated and measured to validate the proposed model. The model calculation results are compared with the measurement results, and the root-mean-square error of the model is below 0.007 up to 66 GHz.
{"title":"CMOS 90 nm multi-bias transistor model Up to 66 GHz","authors":"Yunqiu Wu, Shili Cong, Chenxi Zhao, Huihua Liu, K. Kang","doi":"10.1109/EDAPS.2017.8276926","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8276926","url":null,"abstract":"A multi-bias transistor model is proposed in this paper. The nonlinear drain-source current, the output resistance, and the intrinsic capacitance are fully considered to characterize the transistor's bias-dependent performance. On this basis, the values of the model elements are extracted under different bias conditions. Furthermore, a 90 nm CMOS transistor is fabricated and measured to validate the proposed model. The model calculation results are compared with the measurement results, and the root-mean-square error of the model is below 0.007 up to 66 GHz.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132884197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1109/EDAPS.2017.8277011
Xiaoxian Liu, Zhangming Zhu, Yintang Yang, Qijun Lu, Xiangkun Yin, Yang Liu
The polymer-cavity through-silicon vias (TSVs) on low resistivity silicon (LRSi) are proposed in this letter to reduce the conductive substrate losses for microwave applications, due to that the coupling loss of conventional LRSi is considerable in high speed three-dimensional integrated circuits (3-D ICs). The accurate wideband equivalent circuit model and simplified π-model are derived based on the physical design parameters, which are established by the ADS software. Well agreements between the proposed models and 3D full-wave EM field simulation of Ansoft's HFSS are shown with the operating frequencies up to 20 GHz.
{"title":"Electrical modeling and analysis of polymer-cavity through-silicon vias","authors":"Xiaoxian Liu, Zhangming Zhu, Yintang Yang, Qijun Lu, Xiangkun Yin, Yang Liu","doi":"10.1109/EDAPS.2017.8277011","DOIUrl":"https://doi.org/10.1109/EDAPS.2017.8277011","url":null,"abstract":"The polymer-cavity through-silicon vias (TSVs) on low resistivity silicon (LRSi) are proposed in this letter to reduce the conductive substrate losses for microwave applications, due to that the coupling loss of conventional LRSi is considerable in high speed three-dimensional integrated circuits (3-D ICs). The accurate wideband equivalent circuit model and simplified π-model are derived based on the physical design parameters, which are established by the ADS software. Well agreements between the proposed models and 3D full-wave EM field simulation of Ansoft's HFSS are shown with the operating frequencies up to 20 GHz.","PeriodicalId":329279,"journal":{"name":"2017 IEEE Electrical Design of Advanced Packaging and Systems Symposium (EDAPS)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133290505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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