Pub Date : 2014-04-01DOI: 10.1109/DTIP.2014.7056677
G. De Pasquale, A. Somà, M. Barbato, G. Meneghesso
Within reliability issues in the MEMS field, the contact problem is one of the most complex to model and validate. In fact, it is influenced by many electro-thermo-mechanical parameters that make extremely difficult to predict the damaging effects on the involved surfaces and its implications on the device performances and reliability. The goal of this paper is to analyze the impact wear and the other effects of contact on the electromechanical properties of MEMS by means of dedicated experiments. Long term tests of repetitive impact loading are reported with the goal of relating the excitation parameters to the electrical RF performances degradation of the devices due to impact effects on electrode surfaces.
{"title":"Impact wear and other contact effects on the electro-mechanical reliability of MEMS","authors":"G. De Pasquale, A. Somà, M. Barbato, G. Meneghesso","doi":"10.1109/DTIP.2014.7056677","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056677","url":null,"abstract":"Within reliability issues in the MEMS field, the contact problem is one of the most complex to model and validate. In fact, it is influenced by many electro-thermo-mechanical parameters that make extremely difficult to predict the damaging effects on the involved surfaces and its implications on the device performances and reliability. The goal of this paper is to analyze the impact wear and the other effects of contact on the electromechanical properties of MEMS by means of dedicated experiments. Long term tests of repetitive impact loading are reported with the goal of relating the excitation parameters to the electrical RF performances degradation of the devices due to impact effects on electrode surfaces.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116523299","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056636
A. Bonvilain, Mathilde Gangneron
Further to the first fabrication of strain microgauges on cylindrical metal substrates [1], that we cannot experiment because of problems of wire bonding, we have reviewed the bonding process. These microgauges enable the real-time measurement of the medical needle strain distribution from which its deflection status can be deduced. So this paper deals with the new bonding process of the microgauges and the detailed experimentations. These experimentations consist in constrain the needle and verify that we can measure the strain. They allow also the calculations and the comparison of the theoretical and experimental gauge factor. Finally we discuss about the improvement of the prototype in terms of optimization of the process. And some material questions must find solution.
{"title":"First experimentations of microsensors microfabricated on a long and thin medical needle","authors":"A. Bonvilain, Mathilde Gangneron","doi":"10.1109/DTIP.2014.7056636","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056636","url":null,"abstract":"Further to the first fabrication of strain microgauges on cylindrical metal substrates [1], that we cannot experiment because of problems of wire bonding, we have reviewed the bonding process. These microgauges enable the real-time measurement of the medical needle strain distribution from which its deflection status can be deduced. So this paper deals with the new bonding process of the microgauges and the detailed experimentations. These experimentations consist in constrain the needle and verify that we can measure the strain. They allow also the calculations and the comparison of the theoretical and experimental gauge factor. Finally we discuss about the improvement of the prototype in terms of optimization of the process. And some material questions must find solution.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121477381","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056638
K. Schjølberg-Henriksen, L. Tvedt, S. Moe, E. Poppe, D. Wang, Stein Are Gjelstad, Christopher Mørk, K. Imenes
High temperature silicon direct (fusion) wafer bonding is a process with many application areas. Depending on the application, perfect insulation or zero resistance across the bonded interface is desired, but high bond strength is needed in both cases. Recently, we have presented a hydrophilic bonding process which resulted in ohmic behaviour and negligible electrical resistance of the bonding interface. This paper is an investigation of the bond strength of conductive hydrophilic high-temperature silicon direct wafer bonds. Dicing yield and pull test measurements have been performed. Bonding frames of widths of 100, 200, and 400 μm were fabricated. The measured resistance of chips from boron implanted wafers was 0.35-0.38 Ω, and the resistance of chips from three non-implanted wafers was below 0.68 Ω. The dicing yield was above 89 % for frame widths of 200 μm or wider. Bond strengths of 10.5-13.5 MPa were measured on frames of 400 μm width. There was no significant difference in bond strength between implanted wafers, non-implanted wafers, and wafers with an intentional 60 nm thick SiO2 at the bond interface. The results show that directly bonded silicon bond frames of 200 and 400 μm widths can be conductive and show ohmic behavior while they also have sufficient yield and bond strength for application as device seals in industrial products.
{"title":"Bond strength of conductive Si-Si fusion bonded seals","authors":"K. Schjølberg-Henriksen, L. Tvedt, S. Moe, E. Poppe, D. Wang, Stein Are Gjelstad, Christopher Mørk, K. Imenes","doi":"10.1109/DTIP.2014.7056638","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056638","url":null,"abstract":"High temperature silicon direct (fusion) wafer bonding is a process with many application areas. Depending on the application, perfect insulation or zero resistance across the bonded interface is desired, but high bond strength is needed in both cases. Recently, we have presented a hydrophilic bonding process which resulted in ohmic behaviour and negligible electrical resistance of the bonding interface. This paper is an investigation of the bond strength of conductive hydrophilic high-temperature silicon direct wafer bonds. Dicing yield and pull test measurements have been performed. Bonding frames of widths of 100, 200, and 400 μm were fabricated. The measured resistance of chips from boron implanted wafers was 0.35-0.38 Ω, and the resistance of chips from three non-implanted wafers was below 0.68 Ω. The dicing yield was above 89 % for frame widths of 200 μm or wider. Bond strengths of 10.5-13.5 MPa were measured on frames of 400 μm width. There was no significant difference in bond strength between implanted wafers, non-implanted wafers, and wafers with an intentional 60 nm thick SiO2 at the bond interface. The results show that directly bonded silicon bond frames of 200 and 400 μm widths can be conductive and show ohmic behavior while they also have sufficient yield and bond strength for application as device seals in industrial products.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128528700","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056685
F. Torres, G. Vidal-Álvarez, A. Uranga, N. Barniol
In this work we present a signature of frequency stabilization in a nonlinear regime for a clamped-clamped beam nanoresonator which would be a way to solve the problems of degradation of the resonance frequency in nanoresonators due to their nonlinear response.
{"title":"Enhancement of higher harmonics detectability in a nonlinear nanoresonator","authors":"F. Torres, G. Vidal-Álvarez, A. Uranga, N. Barniol","doi":"10.1109/DTIP.2014.7056685","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056685","url":null,"abstract":"In this work we present a signature of frequency stabilization in a nonlinear regime for a clamped-clamped beam nanoresonator which would be a way to solve the problems of degradation of the resonance frequency in nanoresonators due to their nonlinear response.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126958846","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056647
Ryan Grixti, I. Grech, O. Casha, Jean Marie Darmanin, E. Gatt, J. Micallef
The scope of this paper is to underline the design issues of MEMS microphones and presents a test case designed using the PolyMUMPs process with an additional back-etch processing step. Both circular and square (simply supported and clamped) diaphragm designs are considered. The effect of the back chamber volume on the microphone sensitivity is also investigated. The finalized design is based on the clamped square diaphragm with a bottom sound port. The bias voltage is 6 V and the diaphragm has a side-length of 675 μm. The back-plate includes several holes which amount to a perforation ratio of 0.33. The maximum allowable input pressure before pull-in is 139 dB SPL. The microphone with a back-chamber volume of 6 mm3 has a sensitivity of 8.4 mV/Pa at 94 dB SPL at 1 kHz. The complete package size with the ASIC included is targeted to be 3×2.5×1 mm, assuming that the ASIC is of a comparable size to that of the MEMS sensor.
本文的范围是强调MEMS麦克风的设计问题，并提出了一个使用PolyMUMPs工艺设计的测试用例，该工艺具有额外的背蚀刻处理步骤。考虑圆形和方形(简单支撑和夹紧)隔膜设计。研究了后腔体积对传声器灵敏度的影响。最终的设计是基于带底部声音端口的夹持方形膜片。偏置电压为6v，隔膜边长为675 μm。背板包括几个孔，穿孔比为0.33。拉入前的最大允许输入压力为139 dB SPL。后腔体积为6 mm3的麦克风在94 dB SPL、1 kHz时的灵敏度为8.4 mV/Pa。包含ASIC的完整封装尺寸目标为3×2.5×1 mm，假设ASIC与MEMS传感器的尺寸相当。
{"title":"Feasibility study of a MEMS microphone design using the PolyMUMPs process","authors":"Ryan Grixti, I. Grech, O. Casha, Jean Marie Darmanin, E. Gatt, J. Micallef","doi":"10.1109/DTIP.2014.7056647","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056647","url":null,"abstract":"The scope of this paper is to underline the design issues of MEMS microphones and presents a test case designed using the PolyMUMPs process with an additional back-etch processing step. Both circular and square (simply supported and clamped) diaphragm designs are considered. The effect of the back chamber volume on the microphone sensitivity is also investigated. The finalized design is based on the clamped square diaphragm with a bottom sound port. The bias voltage is 6 V and the diaphragm has a side-length of 675 μm. The back-plate includes several holes which amount to a perforation ratio of 0.33. The maximum allowable input pressure before pull-in is 139 dB SPL. The microphone with a back-chamber volume of 6 mm3 has a sensitivity of 8.4 mV/Pa at 94 dB SPL at 1 kHz. The complete package size with the ASIC included is targeted to be 3×2.5×1 mm, assuming that the ASIC is of a comparable size to that of the MEMS sensor.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132395606","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056673
B. Chariot, N. Sanchez, P. Roux, S. Teixeira
This article describes the first developments of a microfluidic circuit for the continuous generation of monodisperse polymersomes. The generation of these vesicles is made in a consecutive flow focusing cross-junctions structure from non miscible fluids. The device allows generating a stream of polymersomes in two steps. The breaking of a focused water flow creates first water droplets in a solution of diblock polymer and then the double emulsion is generated at the second constriction. This paper will describe microflabrication of the device and a study of the dynamics of droplets formation by high frame rate videomicroscopy. The work has been done on liposome in first steps and them with Pb-b-PEO block polymer in a second time. Finally the paper will decribe the addition of a separation structure for sorting generated vesicles by their size.
{"title":"Double emulsion generation and separation by microfluidic consecutive flow focusing","authors":"B. Chariot, N. Sanchez, P. Roux, S. Teixeira","doi":"10.1109/DTIP.2014.7056673","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056673","url":null,"abstract":"This article describes the first developments of a microfluidic circuit for the continuous generation of monodisperse polymersomes. The generation of these vesicles is made in a consecutive flow focusing cross-junctions structure from non miscible fluids. The device allows generating a stream of polymersomes in two steps. The breaking of a focused water flow creates first water droplets in a solution of diblock polymer and then the double emulsion is generated at the second constriction. This paper will describe microflabrication of the device and a study of the dynamics of droplets formation by high frame rate videomicroscopy. The work has been done on liposome in first steps and them with Pb-b-PEO block polymer in a second time. Finally the paper will decribe the addition of a separation structure for sorting generated vesicles by their size.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131920913","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056637
Liao Kai-Wei, Amarendra Kumar, M. T. Hou, J. Yeh
This paper presents a novel sensing array with tunable sensing ranges for dynamic tactile sensing. Each element in the array contains a droplet with variable shape. By controlling the dielectric force applying on the droplet, the shape of the droplet can be controlled. The sensing range was tuned due to the variation of the droplet shape. This sensing array can be not only used in static tactile sensing but also in dynamic tactile sensing. The experiment result shows the sensing range, from 0.6 N to 1.05 N, can be tuned in 100 ms.
{"title":"Dielectric liquid-based tactile sensing array with tunable sensing range using dielectric force for dynamic tactile sensing","authors":"Liao Kai-Wei, Amarendra Kumar, M. T. Hou, J. Yeh","doi":"10.1109/DTIP.2014.7056637","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056637","url":null,"abstract":"This paper presents a novel sensing array with tunable sensing ranges for dynamic tactile sensing. Each element in the array contains a droplet with variable shape. By controlling the dielectric force applying on the droplet, the shape of the droplet can be controlled. The sensing range was tuned due to the variation of the droplet shape. This sensing array can be not only used in static tactile sensing but also in dynamic tactile sensing. The experiment result shows the sensing range, from 0.6 N to 1.05 N, can be tuned in 100 ms.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133845069","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056655
Wei Xu, A. Bosseboeuf, F. Parrain, E. Martincic
Mirau interferometers are two beam interferometers with coaxial optical beams that are widely used in full-field optical surface profilers. An integrated Mirau interferometer with a MEMS mirror scanner is proposed in this paper. The novelty of the scanner design is the use of self-aligned vertical electrostatic combs made in double SOI wafer technology which allows a large range, bidirectional, and symmetric vertical translation of the reference mirror. Electrostatic and mechanical analytical calculations and Finite Element Modeling simulations were carried out to design and optimize the MEMS scanner. A large bidirectional range (+/-20 μm) motion under 60V applied voltage is achievable. Good flatness of the reference mirror is preserved during motion, what is essential for interferometrie measurements. A fabrication process which minimizes the number of mask levels is proposed. It is based on front and back side Deep Reactive Ion Etching and dry film photoresist lithographic steps.
{"title":"Design of a long range bidirectional MEMS scanner for a tunable 3D integrated Mirau interferometer","authors":"Wei Xu, A. Bosseboeuf, F. Parrain, E. Martincic","doi":"10.1109/DTIP.2014.7056655","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056655","url":null,"abstract":"Mirau interferometers are two beam interferometers with coaxial optical beams that are widely used in full-field optical surface profilers. An integrated Mirau interferometer with a MEMS mirror scanner is proposed in this paper. The novelty of the scanner design is the use of self-aligned vertical electrostatic combs made in double SOI wafer technology which allows a large range, bidirectional, and symmetric vertical translation of the reference mirror. Electrostatic and mechanical analytical calculations and Finite Element Modeling simulations were carried out to design and optimize the MEMS scanner. A large bidirectional range (+/-20 μm) motion under 60V applied voltage is achievable. Good flatness of the reference mirror is preserved during motion, what is essential for interferometrie measurements. A fabrication process which minimizes the number of mask levels is proposed. It is based on front and back side Deep Reactive Ion Etching and dry film photoresist lithographic steps.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"33 1-2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116724932","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056659
A. Brenes, J. Juillard, Filipe Vinci, Santos, Thales Chair
The aim of this paper is to introduce an explanation for the amplitude saturation and inhibition phenomena in resonant MEMS pressure sensors, via the electrostatic coupling of two resonance modes. Our analysis and experimental results reveal that these phenomena may be ubiquitous in electrostatic resonant MEMS sensors.
{"title":"Electrostatically-induced modal crosstalk phenomena in resonant MEMS sensors","authors":"A. Brenes, J. Juillard, Filipe Vinci, Santos, Thales Chair","doi":"10.1109/DTIP.2014.7056659","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056659","url":null,"abstract":"The aim of this paper is to introduce an explanation for the amplitude saturation and inhibition phenomena in resonant MEMS pressure sensors, via the electrostatic coupling of two resonance modes. Our analysis and experimental results reveal that these phenomena may be ubiquitous in electrostatic resonant MEMS sensors.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116056625","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 : 2014-04-01DOI: 10.1109/DTIP.2014.7056666
J. Pons-Nin, S. Gorreta, M. Domínguez, E. Blokhina, D. O'Connell, O. Feely
This paper presents preliminary results obtained with devices fabricated with the new PiezoMUMPS process. Since these devices will be used as resonators in applications based on Pulsed Digital Oscillators, we analyze, both with simulations and measurements, the mechanical vibration modes that can be excited and detected. We also introduce a specific version of PDO for piezoelectric MEMS.
{"title":"Design and test of resonators using PiezoMUMPS technology","authors":"J. Pons-Nin, S. Gorreta, M. Domínguez, E. Blokhina, D. O'Connell, O. Feely","doi":"10.1109/DTIP.2014.7056666","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056666","url":null,"abstract":"This paper presents preliminary results obtained with devices fabricated with the new PiezoMUMPS process. Since these devices will be used as resonators in applications based on Pulsed Digital Oscillators, we analyze, both with simulations and measurements, the mechanical vibration modes that can be excited and detected. We also introduce a specific version of PDO for piezoelectric MEMS.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"92 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124795800","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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