Pub Date : 2008-12-02DOI: 10.1109/ISAF.2008.4693909
N. Balke, P. Yu, L. Wang, R. Ramesh
Retention properties of written nanodots for Pb(Zr0.2Ti0.8)O3 have been investigated. The imaging voltage plays an important role when investigating small unstable domains. Even with an imaging voltage far below the coercive voltage the boundaries of the domains are switched during imaging by what the measured nanodomain stability is strongly influenced
{"title":"CH003: Stability of nanodots in ferroelectric thin films","authors":"N. Balke, P. Yu, L. Wang, R. Ramesh","doi":"10.1109/ISAF.2008.4693909","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693909","url":null,"abstract":"Retention properties of written nanodots for Pb(Zr0.2Ti0.8)O3 have been investigated. The imaging voltage plays an important role when investigating small unstable domains. Even with an imaging voltage far below the coercive voltage the boundaries of the domains are switched during imaging by what the measured nanodomain stability is strongly influenced","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131835587","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693963
S. Summerfelt, John Rodriguez, H. McAdams
Design of ferroelectric memories, F-RAMs, requires an accurate ferroelectric SPICE model. The goal of a good SPICE model is to predict the behavior of the ferroelectric capacitor in the circuit environment.
{"title":"Ferroelectric SPICE model, testing and fitting","authors":"S. Summerfelt, John Rodriguez, H. McAdams","doi":"10.1109/ISAF.2008.4693963","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693963","url":null,"abstract":"Design of ferroelectric memories, F-RAMs, requires an accurate ferroelectric SPICE model. The goal of a good SPICE model is to predict the behavior of the ferroelectric capacitor in the circuit environment.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"152 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133124727","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693873
M. Zipparo
Arrays optimized for conventional B-mode imaging applications are often limited in their ability to transmit power into the body, not by acoustic intensity limits but by face temperature maximums. Furthermore, new imaging modalities that use a long train of transmit pulses to remotely deposit a localized force on tissue are even more limited by array thermal considerations. Losses within the piezoceramic material are an important source of heat generation. Simply replacing the piezo material by one with lower losses will result in poorer imaging performance due to the physical properties and coarser microstructure of most low loss materials. This work describes the use of low loss piezoceramics exhibiting a microstructure that is ideal for forming into fine scale ultrasound arrays. Incorporating this material into multilayer ceramic and composite structures is shown to be an effective way to ameliorate the limitations of the base piezo and result in arrays with acoustic tank and imaging performance that is as good as or better than conventional imaging arrays made using a single layer of a conventional piezo. These arrays are also shown to exhibit reduced heating under equivalent electrical input power.
{"title":"Ultrasound imaging arrays with improved transmit power capability","authors":"M. Zipparo","doi":"10.1109/ISAF.2008.4693873","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693873","url":null,"abstract":"Arrays optimized for conventional B-mode imaging applications are often limited in their ability to transmit power into the body, not by acoustic intensity limits but by face temperature maximums. Furthermore, new imaging modalities that use a long train of transmit pulses to remotely deposit a localized force on tissue are even more limited by array thermal considerations. Losses within the piezoceramic material are an important source of heat generation. Simply replacing the piezo material by one with lower losses will result in poorer imaging performance due to the physical properties and coarser microstructure of most low loss materials. This work describes the use of low loss piezoceramics exhibiting a microstructure that is ideal for forming into fine scale ultrasound arrays. Incorporating this material into multilayer ceramic and composite structures is shown to be an effective way to ameliorate the limitations of the base piezo and result in arrays with acoustic tank and imaging performance that is as good as or better than conventional imaging arrays made using a single layer of a conventional piezo. These arrays are also shown to exhibit reduced heating under equivalent electrical input power.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117273087","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693906
P. Ketsuwan, C. C. Huang, S. Ananta, R. Yimnirun, D. Cann
The Ba(Zn1/3Nb2/3)0.75Ti0.25O3 ceramic was prepared by a conventional mixed oxide. The thermal analysis (TG-DTA) and x-ray diffraction were used for investigating of phases formation. A pure phase of BaZn1/3Nb2/3O3 was obtained and revealed microwave dielectric behavior.
{"title":"Phase formation and dielectric properties of Ba(Zn1/3Nb2/3)0.75Ti0.25O3 ceramic","authors":"P. Ketsuwan, C. C. Huang, S. Ananta, R. Yimnirun, D. Cann","doi":"10.1109/ISAF.2008.4693906","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693906","url":null,"abstract":"The Ba(Zn1/3Nb2/3)0.75Ti0.25O3 ceramic was prepared by a conventional mixed oxide. The thermal analysis (TG-DTA) and x-ray diffraction were used for investigating of phases formation. A pure phase of BaZn1/3Nb2/3O3 was obtained and revealed microwave dielectric behavior.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116842660","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693823
M. Adachi, K. Takeuchi, T. Karaki
(K,Li)NbO3 single crystals were successfully grown from a melt with potassium enriched composition under the condition of shallow temperature gradient using the TSSG technique. The growth was along the ¿100¿ direction in the pseudo-cubic phase. The crystal was allowed to grow laterally from around 10¿30h to obtain the cross section desired. The growing crystal was then lifted up above the melt surface or lifted intermittently at the rate of about 4mm/h, while the melt was cooled. Cracking occurred at the phase transition temperatures of 457 and 220°C for (K,Li)NbO3. Slow cooling fairly eliminated the cracking at the both phase transition points. The completeness of the poling was checked by the dielectric measurements. After poling, the dielectric constant reduced to be around 150.
{"title":"Growth of potassium lithium niobate-tantalate single crystal for piezoelectric applications","authors":"M. Adachi, K. Takeuchi, T. Karaki","doi":"10.1109/ISAF.2008.4693823","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693823","url":null,"abstract":"(K,Li)NbO3 single crystals were successfully grown from a melt with potassium enriched composition under the condition of shallow temperature gradient using the TSSG technique. The growth was along the ¿100¿ direction in the pseudo-cubic phase. The crystal was allowed to grow laterally from around 10¿30h to obtain the cross section desired. The growing crystal was then lifted up above the melt surface or lifted intermittently at the rate of about 4mm/h, while the melt was cooled. Cracking occurred at the phase transition temperatures of 457 and 220°C for (K,Li)NbO3. Slow cooling fairly eliminated the cracking at the both phase transition points. The completeness of the poling was checked by the dielectric measurements. After poling, the dielectric constant reduced to be around 150.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115641693","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693764
S. Alpay
Graded ferroelectrics and ferroelectric multilayers have received great interest as active elements in tunable microwave devices and piezoelectric actuators/sensors. There have been a number of experimental studies that show that these materials have many peculiar properties that cannot be described by a simple series connection of the individual layers that make up the heterostructures. A thermodynamic analysis is presented to demonstrate that ferroelectric multilayers interact through internal elastic, electrical, and electromechanical fields and the ¿strength¿ of the coupling can be quantitatively described using Landau theory of phase transformations, theory of elasticity, and principles of electrostatics. In addition to broken spatial inversion symmetry that can lead to asymmetric thermodynamic potentials, the modeling indicates that the electrostatic coupling between the layers leads to the suppression of ferroelectricity at a critical paraelectric layer thickness for ferroelectric-paraelectric bilayers. This bilayer is expected to have a colossal dielectric/piezoelectric response similar to the anomaly near Curie-Weiss temperature in homogeneous ferroelectrics at this critical thickness. This behavior has the characteristics of a ¿phase transformation.¿ The relative thicknesses of the layers can be used as a design parameter for bilayer, multilayers, and graded heterostructures. We present numerical results on the dielectric and piezoelectric response of BaTiO3/SrTiO3 bilayers, and graded BaTiO3-SrTiO3 (BST) and PbZrO3-PbTiO3 (PZT) compounds.
{"title":"Modeling of graded and multilayer ferroelectrics: Dielectric and piezoelectric response","authors":"S. Alpay","doi":"10.1109/ISAF.2008.4693764","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693764","url":null,"abstract":"Graded ferroelectrics and ferroelectric multilayers have received great interest as active elements in tunable microwave devices and piezoelectric actuators/sensors. There have been a number of experimental studies that show that these materials have many peculiar properties that cannot be described by a simple series connection of the individual layers that make up the heterostructures. A thermodynamic analysis is presented to demonstrate that ferroelectric multilayers interact through internal elastic, electrical, and electromechanical fields and the ¿strength¿ of the coupling can be quantitatively described using Landau theory of phase transformations, theory of elasticity, and principles of electrostatics. In addition to broken spatial inversion symmetry that can lead to asymmetric thermodynamic potentials, the modeling indicates that the electrostatic coupling between the layers leads to the suppression of ferroelectricity at a critical paraelectric layer thickness for ferroelectric-paraelectric bilayers. This bilayer is expected to have a colossal dielectric/piezoelectric response similar to the anomaly near Curie-Weiss temperature in homogeneous ferroelectrics at this critical thickness. This behavior has the characteristics of a ¿phase transformation.¿ The relative thicknesses of the layers can be used as a design parameter for bilayer, multilayers, and graded heterostructures. We present numerical results on the dielectric and piezoelectric response of BaTiO3/SrTiO3 bilayers, and graded BaTiO3-SrTiO3 (BST) and PbZrO3-PbTiO3 (PZT) compounds.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121761860","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693785
A. Sheikh, V. Mathe
Our studies comprise dielectric and magnetoelectric properties of CoFe2O4 and PMNPT ME composites. The individual phases were prepared by conventional ceramic method. The particulate composites of ferrite and ferroelectric phases were prepared in ferroelectric rich region. The presences of both the phases in the composites were characterized by using X-ray diffraction technique. The SEM images were used to study the microstructure of composites. The variation of dielectric constant was studied as a function of temperature at fixed frequencies viz. 1 kHz, 10 kHz, 100 kHz and 1MHz. The polarization vs. electric field (P-E) hysteresis loop for all the composites were also studied which shows their ferroelectric nature.
{"title":"Dielectric and ferroelectric properties of PMN-PT- CoFe2O4 composites","authors":"A. Sheikh, V. Mathe","doi":"10.1109/ISAF.2008.4693785","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693785","url":null,"abstract":"Our studies comprise dielectric and magnetoelectric properties of CoFe2O4 and PMNPT ME composites. The individual phases were prepared by conventional ceramic method. The particulate composites of ferrite and ferroelectric phases were prepared in ferroelectric rich region. The presences of both the phases in the composites were characterized by using X-ray diffraction technique. The SEM images were used to study the microstructure of composites. The variation of dielectric constant was studied as a function of temperature at fixed frequencies viz. 1 kHz, 10 kHz, 100 kHz and 1MHz. The polarization vs. electric field (P-E) hysteresis loop for all the composites were also studied which shows their ferroelectric nature.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122109315","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693739
M. Letz, M.J. Davis, B. Hoppe
Obtaining a glass ceramic via devitrification of a fully amorphous glass phase leads to a pore-free material, in which crystallites with their ferroelectric phase are embedded in a residual glass matrix. This matrix in turn forms a close-to-ideal dielectric. Such a structure offers, in principle, several advantages over conventional sintered ceramics, particularly with respect to ageing and fatigue. We show examples of ferroelectric glass ceramics in which the composition of the ferroelectric phase as well as the size of the crystallites are varied in a systematic way. The dielectric and structural properties are discussed in detail.
{"title":"Glass ceramics with ferroelectric crystalline phases","authors":"M. Letz, M.J. Davis, B. Hoppe","doi":"10.1109/ISAF.2008.4693739","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693739","url":null,"abstract":"Obtaining a glass ceramic via devitrification of a fully amorphous glass phase leads to a pore-free material, in which crystallites with their ferroelectric phase are embedded in a residual glass matrix. This matrix in turn forms a close-to-ideal dielectric. Such a structure offers, in principle, several advantages over conventional sintered ceramics, particularly with respect to ageing and fatigue. We show examples of ferroelectric glass ceramics in which the composition of the ferroelectric phase as well as the size of the crystallites are varied in a systematic way. The dielectric and structural properties are discussed in detail.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124413351","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693790
N. Ortega, Ashok Kumar, R. Katiyar
Structural, microscopic, magnetization, and dielectric properties of the multiferroic composite ceramics consisting of BiFeO3 (BTO)1¿x¿NiFe2O4 (NFO)x (x = 0.05, 0.1, 0.15, 0.2, 0.3, 0.4) prepared by conventional solid state route were investigated. The x-ray diffraction, Raman spectra, and SEM micrographs showed the presence of constituent phases in the composite. The variation of the dielectric constant with frequency in the range of 100 Hz to 1 MHz shows both, decrease in ¿¿ and significant frequency dispersion accompanied with an increase in the loss tangent, with increase in NFO concentration in the composites. The BTO-NFO composites exhibited well-defined magnetic hysteresis loops at room temperature. The temperature variation of the magnetization showed indirect converse magneto electric coupling for the critical value (x=0.40) of the composite near the BTO phase transition (orthorhombic-tetragonal).
{"title":"Structural, dielectric, electrical and magnetic properties of multiferroic BaTiO3-NiFe2O4 composite ceramic","authors":"N. Ortega, Ashok Kumar, R. Katiyar","doi":"10.1109/ISAF.2008.4693790","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693790","url":null,"abstract":"Structural, microscopic, magnetization, and dielectric properties of the multiferroic composite ceramics consisting of BiFeO3 (BTO)1¿x¿NiFe2O4 (NFO)x (x = 0.05, 0.1, 0.15, 0.2, 0.3, 0.4) prepared by conventional solid state route were investigated. The x-ray diffraction, Raman spectra, and SEM micrographs showed the presence of constituent phases in the composite. The variation of the dielectric constant with frequency in the range of 100 Hz to 1 MHz shows both, decrease in ¿¿ and significant frequency dispersion accompanied with an increase in the loss tangent, with increase in NFO concentration in the composites. The BTO-NFO composites exhibited well-defined magnetic hysteresis loops at room temperature. The temperature variation of the magnetization showed indirect converse magneto electric coupling for the critical value (x=0.40) of the composite near the BTO phase transition (orthorhombic-tetragonal).","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121538558","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 : 2008-12-02DOI: 10.1109/ISAF.2008.4693947
S. Anton, A. Erturk, D. Inman
Small, unmanned air vehicles (UAV) are used for reconnaissance by the military. Many of these are all electric with batteries as the primary source of energy. This talk explores the idea of extending the battery life (or flight time) of an electric radio controlled plane by using several harvesting concepts combined into one aircraft. Piezoceramic based harvesting using fiber based piezoceramic composites are in integrated into the wings. A cantilever type actuator is integrated into the fuselage and solar panels are integrated into the upper surfaces. Experimental flight information combined with theoretical analysis concerning the optimal integration of material will be presented.
{"title":"Energy harvesting from small unmmaned air vehicles","authors":"S. Anton, A. Erturk, D. Inman","doi":"10.1109/ISAF.2008.4693947","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693947","url":null,"abstract":"Small, unmanned air vehicles (UAV) are used for reconnaissance by the military. Many of these are all electric with batteries as the primary source of energy. This talk explores the idea of extending the battery life (or flight time) of an electric radio controlled plane by using several harvesting concepts combined into one aircraft. Piezoceramic based harvesting using fiber based piezoceramic composites are in integrated into the wings. A cantilever type actuator is integrated into the fuselage and solar panels are integrated into the upper surfaces. Experimental flight information combined with theoretical analysis concerning the optimal integration of material will be presented.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124021205","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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