{"title":"Sputtering Highly C-axis-oriented AlN films on Langasite Substrate","authors":"S. Wu, Maw-Shung Lee, R. Ro, J. Tsai, D. Hwu","doi":"10.1109/ISAF.2007.4393197","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393197","url":null,"abstract":"Highly c-axis-oriented and fine structural AIN films were successfully prepared on Langasite substrate (LGS, La3Ga5SiO14) by RF magnetron sputtering. The crystalline structure of the films was determined by X-ray diffraction (XRD) and the surface microstructure of films was quantitatively investigated by using scanning electron microscope (SEM) and atomic force microscope (AFM). Different sputtering times (1 hr, 2 hr and 3 hr) were used to deposit the films, and the thickness of films were 0.77 mum, 1.89 mum and 2.86 mum respectively. The result exhibited the films with 0.77 mum were amorphous structures. The films with 1.89 mum were mixed-orientation AIN crystalline structures, including (002) and (103) planes. As the films thickness increased to 2.86 mum, the highly c-axis-oriented AIN crystalline structures were exhibited.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131237003","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}
J. Scott, F. Morrison, Y. K. Hoo, A. Milliken, H. Fan, S. Kawasaki, M. Miyake, T. Tatsuta, O. Tsuji
{"title":"Ferroelectric Thin-Film Devices: Failure Mechanisms and New Prototype Nano-Structures","authors":"J. Scott, F. Morrison, Y. K. Hoo, A. Milliken, H. Fan, S. Kawasaki, M. Miyake, T. Tatsuta, O. Tsuji","doi":"10.1109/ISAF.2007.4393150","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393150","url":null,"abstract":"Several fundamental physics problems concerning ferroelectric thin films are discussed with direct application to industry problems. The first is a model of dielectric breakdown under d.c. voltage stressing, extended from single capacitor films to multilayer capacitors (MLCs). The second is an analysis of flash-over (arcing) breakdown in MLCs, including those with base metal electrodes (Ni). The third is the demonstration that any equivalent circuit model for real ferroelectric memories (FRAMs) must include a constant phase element (CPE). We then consider novel new prototype devices with industry potential for commercialization: three-dimensional [3D] DRAM capacitor trenches; piezoelectric nanotubes; and carbon nano-wire arrays with ferroelectric tips.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132943554","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}
{"title":"Low Temperature Preparation of Bismuth-Related Ferroelectrics by Hydrothermal Synthesis","authors":"A. Inoue, Tho Truong Nguyen, M. Noda, M. Okuyama","doi":"10.1109/ISAF.2007.4393193","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393193","url":null,"abstract":"BIT powder is prepared by hydrothermal synthesis. It is found that the formation of BIT powder is affected by KOH concentration because the XRD intensity increases with increasing the KOH concentration less than 2.0 M. The products are yellowish gray and consist of microscopic lamellar platelets of 0.5 -1.5 mum. Treatment tempereatures are 160 -240 deg C and is decreased with increasing the holding time. The BIT thin films are prepared below 350 deg C by the sol-gel method and hydrothermal treatment for 3 h in Bi(OH)3 0.14 M and KOH 0.01 M mixture solution. The BIT thin film prepared under the optimized condition have hysteresis loops with a good squareness. When 5 V is applied to the BIT film, the polarization at zero electric field is 0.9 muC/cm2 and current density is 8.1x10-6 A/cm2.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132100974","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}
I. Levin, M. Stennett, G. C. Miles, D. I. Woodward, A. West, I. Reaney
{"title":"Octahedral Tilting and Ferroelectric Order in Tetragonal Tungsten Bronze-Like Dielectrics","authors":"I. Levin, M. Stennett, G. C. Miles, D. I. Woodward, A. West, I. Reaney","doi":"10.1109/ISAF.2007.4393236","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393236","url":null,"abstract":"The onset of classic ferroelectric behavior in tetragonal tungsten bronze-like dielectrics Ba2LaxNd1-xNb3Ti2O15 was attributed to a strong coupling between local polar displacements and a certain type of octahedral tilting. The ferroelectric phase transition in these systems is associated with a transformation of an incommensurate tilted structure to a distinct commensurate superstructure. The driving force for commensurate tilting increases as the average ionic radius of the rare-earth ion that reside in perovskite type channels decreases. No classical ferroelectric transition is observed (down to 100 K) for compositions with x>0.75, which remain incommensurate and exhibit only relaxor behavior below room temperature.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132183979","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}
{"title":"Determination of Lumped Element Package Model for Radio Frequency Surface Acoustic Wave Device Using Neural Network Techniques","authors":"S.T. Wang, Zhi-Feng Xie, Tzu-Te Liu, R. Hwang","doi":"10.1109/ISAF.2007.4393395","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393395","url":null,"abstract":"Electronic packaging has a significant influence on RF surface acoustic wave (SAW) device. Hence, how to incorporate packaging effects into SAW simulation is an important issue. In this paper, neural network was employed to determine the lumped element models of bonding pads. As an example, an RF SAW filter used in GPS system was examined. The result showed a good agreement with that obtained from full wave EM simulator.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134644892","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}
I. Mina, G.H. Kim, I. Kim, S. Park, K. Choi, T. Jackson, R. Tutwiler, S. Trolier-McKinstry
{"title":"High Frequency Piezoelectric MEMS Devices","authors":"I. Mina, G.H. Kim, I. Kim, S. Park, K. Choi, T. Jackson, R. Tutwiler, S. Trolier-McKinstry","doi":"10.1109/ISAF.2007.4393375","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393375","url":null,"abstract":"High frequency ultrasound array transducers are being explored for high resolution imaging systems. This increase in resolution is made possible by enabling a simultaneous increase in operating frequency (50 MHz to about 1 GHz) and close-coupling of the electrical circuitry. Several different processing methods are being explored to fabricate array transducers. In one implementation, the piezoelectric transducer is prepared by mist deposition of PbZr0.52Ti0.48O3 (PZT) films over Ni posts. In addition, a xylophone bar transducer has also been prototyped, again using thin film PZT as the active piezoelectric layer. Because the drive voltages of these transducers are low, close coupling of the electrical circuitry is possible. A CMOS transceiver for a 9 element-array has been fabricated in 0.35 mum process technology. The first generation CMOS transceiver chip contains beamforming electronics, receiver circuitry, and analog to digital converters with 27 Kbyte on-chip buffer memory.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"25 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133719899","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}
T. Kijima, T. Aoyama, H. Miyazawa, Y. Hamada, K. Ohashi, M. Nakayama, N. Furuya, A. Matsumoto, E. Natori, K. Tanaka, T. Shimoda
{"title":"Ferroelectric Random Access Memory Using Pb(Zr,Ti,Nb)O3 Films","authors":"T. Kijima, T. Aoyama, H. Miyazawa, Y. Hamada, K. Ohashi, M. Nakayama, N. Furuya, A. Matsumoto, E. Natori, K. Tanaka, T. Shimoda","doi":"10.1109/ISAF.2007.4393155","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393155","url":null,"abstract":"We have succeeded in fabricating Pb(Zr,Ti,Nb)O3 (PZTN) thin films with 20-atomic% Nb at B site in ABO3 structure, which was suitable for high density and reliable ferroelectric random access memory (FeRAM). A sol-gel spin-coating method was used to prepare the PZTN thin films. 1 mol% Si co-doping was applied to promote the solid-solution of Nb atom into the original Pb(Zr,Ti)O3 films. We suggested that in our PZTN the oxygen vacancies were well suppressed due to Nb substitution comparing with conventional Pb(Zr,Ti)O3 (PZT). We also succeeded in obtaining excellent electric properties in 1times1 mum2 capacitors with PZTN. In addition, we confirmed the no data degradation and the high reliability of our PZTN material has been demonstrated by 64 k-bits FeRAM chip operation.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115548770","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}
{"title":"Development of Multilayered SrTiO3 Thin-Film Capacitors For Embedded Passive Applications","authors":"Shuqiang Wang, A. Hattori, Y. Ozeki, H. Ogawa","doi":"10.1109/ISAF.2007.4393306","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393306","url":null,"abstract":"Multilayered thin-film capacitors (MLTFC) with SrTiO3 (STO) dielectric and Pt electrode thin layers were fabricated on polycrystalline alumina substrates, in which amorphous STO dielectric thin layers with thicknesses of 100-300 nm were formed using a cost-effective aerosol chemical vapor deposition (ASCVD) method. The MLTFC with up to ten-layer dielectric layers and total thickness of 0.2-0.25 mm, reached capacitance densities of 100-900 nF/cm2. Further increase in capacitance density of the MLTFC was tried by reduction in thickness and crystallization of STO dielectric thin layers. Three forms of MLTFC (chips, sheets and substrates) are being developed for embedded passive applications.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115921481","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}
{"title":"(Na0.475K0.475Li0.05)(Nb0.92Ta0.05Sb0.03)O3 lead-free ceramics with addition of CeO2","authors":"T. Lee, K. Kwok, H. Chan","doi":"10.1109/ISAF.2007.4393364","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393364","url":null,"abstract":"Lead-free piezoelectric ceramics (Na<sub>0.475</sub>K<sub>0.475</sub>Li<sub>0.05</sub>)(Nb<sub>0.92</sub>Ta<sub>0.05</sub>Sb<sub>0.03</sub>)O<sub>3</sub> added with different amounts of CeO<sub>2</sub> have been prepared by a conventional mixed-oxide method. After the addition of CeO<sub>2</sub>, the sintering performance of the ceramics is greatly improved. The ceramics can be well-sintered at a higher temperature, and hence have a higher density and better piezoelectric and dielectric properties. For the ceramic added with 0.4 wt% CeO<sub>2</sub>, the piezoelectric and dielectric properties become optimum, giving d<sub>33</sub>=246 pC/N, k<sub>p</sub>=0.50, epsiv<sub>r</sub>=1300 and tandelta=4%.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123479630","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}
{"title":"First Principles Calculations for Valence States of Mn in SrTiO3","authors":"Y. Iwazaki, T. Suzuki, H. Kishi, S. Tsuneyuki","doi":"10.1109/ISAF.2007.4393230","DOIUrl":"https://doi.org/10.1109/ISAF.2007.4393230","url":null,"abstract":"The valence change mechanism of doped Mn in SrTiO<sub>3</sub> has been discussed on the basis of the first-principles calculation results. These results show that the crystal with Mn<sup>2+</sup> is stabilized by a peculiar tilting deformation of the MnO<sub>6</sub> octahedron, whereas the crystal with Mn<sup>4+</sup> does not exhibit such tilting. The valence of Mn is closely related to the lattice deformation, and the experimentally observed change in the valence of Mn in SrTiO<sub>3</sub> can be well explained by the thermal excitations of the tilting modes of MnO<sub>6</sub>.","PeriodicalId":321007,"journal":{"name":"2007 Sixteenth IEEE International Symposium on the Applications of Ferroelectrics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122050022","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}