Pub Date : 2014-04-01DOI: 10.1109/DTIP.2014.7056687
Mengqing Liu, Dong F. Wang, Shouhei Shiga, T. Ishida, R. Maeda
A “crescent-shaped” binding alignment mark, more applicable to the self-alignment than reported “tear-drop/elliptical hole” pattern, was designed and comparatively studied with other possible alignment marks by introducing the overlap ratio analysis (DTIP 2011). Recently, in order to apply this novel design to micro-parts with positive and negative poles on the binding sites, a modified “crescent-shaped” pattern with an insulated space area, defined as “crescent-shaped/interval” for self-alignment of micro-parts with two poles was further proposed and discussed. In this report however, the self-alignment process has been in-situ observed and studied using a “square” binding alignment pattern with relatively higher energy barrier but four fully aligned orientations at four off-set angles. Sequential images reveal a slow translational motion in the early stage followed by a faster rotational alignment. The conductivity evaluation before and after the self-alignment of micro-parts has been also preliminarily considered.
{"title":"Crescent shaped patterns for self-alignment of micro-parts: Part II — Self-alignment demonstration and conductivity evaluation","authors":"Mengqing Liu, Dong F. Wang, Shouhei Shiga, T. Ishida, R. Maeda","doi":"10.1109/DTIP.2014.7056687","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056687","url":null,"abstract":"A “crescent-shaped” binding alignment mark, more applicable to the self-alignment than reported “tear-drop/elliptical hole” pattern, was designed and comparatively studied with other possible alignment marks by introducing the overlap ratio analysis (DTIP 2011). Recently, in order to apply this novel design to micro-parts with positive and negative poles on the binding sites, a modified “crescent-shaped” pattern with an insulated space area, defined as “crescent-shaped/interval” for self-alignment of micro-parts with two poles was further proposed and discussed. In this report however, the self-alignment process has been in-situ observed and studied using a “square” binding alignment pattern with relatively higher energy barrier but four fully aligned orientations at four off-set angles. Sequential images reveal a slow translational motion in the early stage followed by a faster rotational alignment. The conductivity evaluation before and after the self-alignment of micro-parts has been also preliminarily considered.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"67 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":"131536003","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.2014.7056688
Bin Sun, R. Sawada, Zhuo-qing Yang, Yi Zhang, T. Itoh, R. Maeda
This paper presents an electromagnetically-actuated single optical fiber scanner that utilizes its high-order resonance modal and tilt microcoil to realize a larger scanning angle. The device is fabricated on the surface of a thin polymer tube with 1mm diameter by our developed spray coating and cylindrical projection lithography systems, which could be used as ultra-thin medical endoscope. In order to realize the electromagnetically-driven scanning, a cylindrical magnet is fixed at the center of the polyimide pipe by an optical fiber. When an AC power is supplied to the microcoil, the fiber scanner is actuated under a certain frequency. The modal and dynamic response of the designed scanner under high-order vibration has been simulated and analyzed. The microcoil with 60° tilt angle is fabricated by wet etching and maskless electroplating processes. The electromagnetic property and maximum driven displacement of the fabricated device have been also evaluated, which is generally in accordance with that simulated. Finally, the electroplated microcoil of 60° tilt-angle, 40μm line width, 40μm line spacing and 15μm thickness has been obtained successfully.
{"title":"Design and fabrication of driving microcoil with large tilt-angle for medical scanner application","authors":"Bin Sun, R. Sawada, Zhuo-qing Yang, Yi Zhang, T. Itoh, R. Maeda","doi":"10.1109/DTIP.2014.7056688","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056688","url":null,"abstract":"This paper presents an electromagnetically-actuated single optical fiber scanner that utilizes its high-order resonance modal and tilt microcoil to realize a larger scanning angle. The device is fabricated on the surface of a thin polymer tube with 1mm diameter by our developed spray coating and cylindrical projection lithography systems, which could be used as ultra-thin medical endoscope. In order to realize the electromagnetically-driven scanning, a cylindrical magnet is fixed at the center of the polyimide pipe by an optical fiber. When an AC power is supplied to the microcoil, the fiber scanner is actuated under a certain frequency. The modal and dynamic response of the designed scanner under high-order vibration has been simulated and analyzed. The microcoil with 60° tilt angle is fabricated by wet etching and maskless electroplating processes. The electromagnetic property and maximum driven displacement of the fabricated device have been also evaluated, which is generally in accordance with that simulated. Finally, the electroplated microcoil of 60° tilt-angle, 40μm line width, 40μm line spacing and 15μm thickness has been obtained successfully.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"12 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":"131192109","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.2014.7056675
Regine Behielt, T. Kunzig, G. Schrag
We present an extensive study on dielectric charging effects, one of the major problems that limit the reliability of electrostatically actuated RF-MEMS switches and, thus, their way into a broad commercial application. For the first time, we are able to provide quantitative statements on the amount of charge injected into the dielectric layers. They result from monitoring the long-term evolution of the switching voltages of the device under test recorded by a novel, on-purpose developed measurement set-up, which enables temperature-dependent investigations. Furthermore, the origin of the parasitic charges, their impact on the switching operation and measures to remove them from the dielectric layers could be identified.
{"title":"Long-term investigations of RF-MEMS switches on failure mechanisms induced by dielectric charging","authors":"Regine Behielt, T. Kunzig, G. Schrag","doi":"10.1109/DTIP.2014.7056675","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056675","url":null,"abstract":"We present an extensive study on dielectric charging effects, one of the major problems that limit the reliability of electrostatically actuated RF-MEMS switches and, thus, their way into a broad commercial application. For the first time, we are able to provide quantitative statements on the amount of charge injected into the dielectric layers. They result from monitoring the long-term evolution of the switching voltages of the device under test recorded by a novel, on-purpose developed measurement set-up, which enables temperature-dependent investigations. Furthermore, the origin of the parasitic charges, their impact on the switching operation and measures to remove them from the dielectric layers could be identified.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"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":"114851275","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.2014.7056649
Bin Tang, Kazuo Sato, Shiwei Xi, Guofen Xie, Mingqiu Yao, W. Su, De Zhang, Yongsheng Cheng
This paper reports a capacitive accelerometer structure with highly symmetrical eight springs and a mass. The accelerometer structure is formed simply by multilayer oxidation and wet etching (MOWE) technique, avoiding the generally adopted deep-groove photolithography when fabricating the thin spring. TMAH+Triton is selected as the etchant because it not only provides the minimum undercutting at the mass corner, thus saving much space of the compensation parts, but also allows the good control of spring thickness at low etch rate. The advanced accelerometer performance could be expected due to the symmetrical structure, the large proof mass, controllable spring shape, the narrow uniform capacitive gap, and the IC-compatible process.
{"title":"Fabrication of a symmetrical accelerometer structure","authors":"Bin Tang, Kazuo Sato, Shiwei Xi, Guofen Xie, Mingqiu Yao, W. Su, De Zhang, Yongsheng Cheng","doi":"10.1109/DTIP.2014.7056649","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056649","url":null,"abstract":"This paper reports a capacitive accelerometer structure with highly symmetrical eight springs and a mass. The accelerometer structure is formed simply by multilayer oxidation and wet etching (MOWE) technique, avoiding the generally adopted deep-groove photolithography when fabricating the thin spring. TMAH+Triton is selected as the etchant because it not only provides the minimum undercutting at the mass corner, thus saving much space of the compensation parts, but also allows the good control of spring thickness at low etch rate. The advanced accelerometer performance could be expected due to the symmetrical structure, the large proof mass, controllable spring shape, the narrow uniform capacitive gap, and the IC-compatible process.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"44 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":"123215930","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.2014.7056681
M. M. Saleem, A. Somà, G. De Pasquale
This paper presents the design and modeling of the MEMS mechanical fatigue in the presence of stress raising notches. FEM models are realized to study the effect of notch geometric parameters on the stress concentration factor of the gold specimen subjected to tensile loading. Test structures with three different specimens, i.e. without notch, with single notch and with a double notch are modeled considering fabrication process constraints. Maximum axial stresses produced in the specimens and the corresponding stress concentration factors for the notched specimens are obtained using FEM modeling.
{"title":"Design and FEM modeling of notch effect in gold microbeams","authors":"M. M. Saleem, A. Somà, G. De Pasquale","doi":"10.1109/DTIP.2014.7056681","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056681","url":null,"abstract":"This paper presents the design and modeling of the MEMS mechanical fatigue in the presence of stress raising notches. FEM models are realized to study the effect of notch geometric parameters on the stress concentration factor of the gold specimen subjected to tensile loading. Test structures with three different specimens, i.e. without notch, with single notch and with a double notch are modeled considering fabrication process constraints. Maximum axial stresses produced in the specimens and the corresponding stress concentration factors for the notched specimens are obtained using FEM modeling.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"91 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":"122440448","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.2014.7056640
M. Malak, K. Jefimovs, Irène Philipoussis, J. di Francesco, B. Guldimann, T. Scharf
Spectral analysis can be achieved using various optical microsystems. Amongst, we can cite: Fabry-Pérot and Michelson interferometers, Array Waveguide Grating and Standing wave Fourier Transform spectrometer. Recently, a study aiming miniaturization has been conducted on focal Plane Array Spectrometers (FPAS). Up to the authors' knowledge, this is the first report about a realization of a compact Fourier Transform optical spectrometer based on micro-nano structures, combining a polymer-based integrated optical circuit with movable external mirror for increased sampling and high precision.
{"title":"Functional micro-nano structures for on-chip fourier transform spectrometers","authors":"M. Malak, K. Jefimovs, Irène Philipoussis, J. di Francesco, B. Guldimann, T. Scharf","doi":"10.1109/DTIP.2014.7056640","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056640","url":null,"abstract":"Spectral analysis can be achieved using various optical microsystems. Amongst, we can cite: Fabry-Pérot and Michelson interferometers, Array Waveguide Grating and Standing wave Fourier Transform spectrometer. Recently, a study aiming miniaturization has been conducted on focal Plane Array Spectrometers (FPAS). Up to the authors' knowledge, this is the first report about a realization of a compact Fourier Transform optical spectrometer based on micro-nano structures, combining a polymer-based integrated optical circuit with movable external mirror for increased sampling and high precision.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"45 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":"124127052","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.2014.7056654
S. Dhanekar, R. Tiwari, Bhagaban Behera, S. Chandra, R. Balasubramaniam
In the present work, we report the design, fabrication, packaging and testing of a micro-mixer microfluidic device in 2" diameter silicon substrate. For this purpose, long and deep (~ 80 μm) channels in silicon were formed employing modified reactive ion etching (RIE) process. The RIE process parameters were carefully optimised for obtaining fast etch rate for creating 80 μm deep channels. Silicon wafers were anodically bonded to a Corning® 7740 glass plate of identical sizes, for the purpose of fluid confinement. Through holes were made either in silicon substrate or in glass plate for formation of input/output ports. The channels were characterized using stylus and optical profilometers. The micromixer device was packaged in a polycarbonate housing and pressure drop versus flow rate measurements were carried out. The Reynolds Number and Friction Factor were calculated and it was concluded that the flow of gas was laminar at flow rates of oxygen ranging from 0.4 to 25 seem.
{"title":"Development of reactive ion etching process for deep etching of silicon for micro-mixer device fabrication","authors":"S. Dhanekar, R. Tiwari, Bhagaban Behera, S. Chandra, R. Balasubramaniam","doi":"10.1109/DTIP.2014.7056654","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056654","url":null,"abstract":"In the present work, we report the design, fabrication, packaging and testing of a micro-mixer microfluidic device in 2\" diameter silicon substrate. For this purpose, long and deep (~ 80 μm) channels in silicon were formed employing modified reactive ion etching (RIE) process. The RIE process parameters were carefully optimised for obtaining fast etch rate for creating 80 μm deep channels. Silicon wafers were anodically bonded to a Corning® 7740 glass plate of identical sizes, for the purpose of fluid confinement. Through holes were made either in silicon substrate or in glass plate for formation of input/output ports. The channels were characterized using stylus and optical profilometers. The micromixer device was packaged in a polycarbonate housing and pressure drop versus flow rate measurements were carried out. The Reynolds Number and Friction Factor were calculated and it was concluded that the flow of gas was laminar at flow rates of oxygen ranging from 0.4 to 25 seem.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"46 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":"127107330","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.2014.7056703
M. Nomura
There are some physical similarities in photonics and phononics; photon and phonon transports can be coherently controlled by micro/nanoscale artificial crystal structures. Similarities and non-similarities of two photon and phonon transports will be discussed and we focus on the coherent manipulation of phonon transport by phononic crystal nanostructures. We also discuss possibility of thermal conduction nanoengineering with some simulation results in silicon at room temperature. The multiple scale physics in phononic systems makes phonon transport control, which is heat transfer, more difficult, but some challenges to accomplish the goal will be shown.
{"title":"From photonic to phononic: Toward heat transfer control by MEMS nanostructures","authors":"M. Nomura","doi":"10.1109/DTIP.2014.7056703","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056703","url":null,"abstract":"There are some physical similarities in photonics and phononics; photon and phonon transports can be coherently controlled by micro/nanoscale artificial crystal structures. Similarities and non-similarities of two photon and phonon transports will be discussed and we focus on the coherent manipulation of phonon transport by phononic crystal nanostructures. We also discuss possibility of thermal conduction nanoengineering with some simulation results in silicon at room temperature. The multiple scale physics in phononic systems makes phonon transport control, which is heat transfer, more difficult, but some challenges to accomplish the goal will be shown.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"11 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":"132630217","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.2014.7056678
A. Lucibello, E. Proietti, R. Marcelli, G. Bartolucci, G. de Angelis
This paper presents the design of distributed MEMS phase shifters by means of the image-parameters method. The proposed analytic approach utilizes a more precise modeling of the MEMS device with respect to that one usually adopted in literature. The most important analytic aspects concerning the synthesis technique are presented. As a demonstration of the method a structure characterized by a differential phase shift value of 90° is designed and simulated, exhibiting very good electric performance.
{"title":"Analytic design method for distributed RF MEMS phase shifters","authors":"A. Lucibello, E. Proietti, R. Marcelli, G. Bartolucci, G. de Angelis","doi":"10.1109/DTIP.2014.7056678","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056678","url":null,"abstract":"This paper presents the design of distributed MEMS phase shifters by means of the image-parameters method. The proposed analytic approach utilizes a more precise modeling of the MEMS device with respect to that one usually adopted in literature. The most important analytic aspects concerning the synthesis technique are presented. As a demonstration of the method a structure characterized by a differential phase shift value of 90° is designed and simulated, exhibiting very good electric performance.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"23 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":"115975044","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.2014.7056664
R. Voicu, R. Gavrila, C. Obreja, R. Muller, A. Baracu, M. Michałowski, Z. Rymuza
Natural frequencies of an array of microcantilevers designed with different dimensions were analysed using computer simulations. Four different types of polysilicon were obtained in different processing conditions varying the deposition temperatures (580°C, 610°C, 630°C, 650°C). A topography scan, a comparative friction test and adhesive tests (pull off-force measurement) were carried out using Atomic Force Microscope (AFM) in order to characterize the material properties. Mechanical properties such as hardness and Young's modulus have been investigated using the nanoindenter technique. The microcantilevers have been manufactured using polysilicon as structural material and surface micromachining technique.
{"title":"Design and analysis of polysilicon thin layers and MEMS vibrating structures","authors":"R. Voicu, R. Gavrila, C. Obreja, R. Muller, A. Baracu, M. Michałowski, Z. Rymuza","doi":"10.1109/DTIP.2014.7056664","DOIUrl":"https://doi.org/10.1109/DTIP.2014.7056664","url":null,"abstract":"Natural frequencies of an array of microcantilevers designed with different dimensions were analysed using computer simulations. Four different types of polysilicon were obtained in different processing conditions varying the deposition temperatures (580°C, 610°C, 630°C, 650°C). A topography scan, a comparative friction test and adhesive tests (pull off-force measurement) were carried out using Atomic Force Microscope (AFM) in order to characterize the material properties. Mechanical properties such as hardness and Young's modulus have been investigated using the nanoindenter technique. The microcantilevers have been manufactured using polysilicon as structural material and surface micromachining technique.","PeriodicalId":268119,"journal":{"name":"2014 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP)","volume":"23 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":"123785459","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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