A wafer-level assembled SAW filter on 36Y-X LiTaO3 with a size of 1.6x0.8 mm is presented. The SAW filter has six solder balls with a size of 0.25 mm diameters. The reason of the use of the 0.25 mm balls is that it is easy to mount the devices onto a printed circuit board using a conventional placement machine. The SAW filter is designed for a GPS RF stage application and has a center frequency of 1.5 GHz. The frequency characteristics of the SAW filter are almost the same as the ceramic packaged SAW filter. An insertion loss of 1.1 dB was obtained. Furthermore, a smaller SAW filter with 1.0x0.8 mm in size is demonstrated.
{"title":"10E-3 GPS SAW Filter Using A Wafer Level Technique","authors":"F. Shiba, M. Yamazaki, O. Iijima, H. Yatsuda","doi":"10.1109/ULTSYM.2007.239","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.239","url":null,"abstract":"A wafer-level assembled SAW filter on 36Y-X LiTaO3 with a size of 1.6x0.8 mm is presented. The SAW filter has six solder balls with a size of 0.25 mm diameters. The reason of the use of the 0.25 mm balls is that it is easy to mount the devices onto a printed circuit board using a conventional placement machine. The SAW filter is designed for a GPS RF stage application and has a center frequency of 1.5 GHz. The frequency characteristics of the SAW filter are almost the same as the ceramic packaged SAW filter. An insertion loss of 1.1 dB was obtained. Furthermore, a smaller SAW filter with 1.0x0.8 mm in size is demonstrated.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"12 1","pages":"937-940"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74604305","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}
We have investigated controlling the phase velocity of a surface acoustic wave (SAW) by a microelectromechanical switch fabricated on a high coupling piezoelectric substrate. The principle is based on the interaction of the evanescent surface potential of the SAW with the conductive switch. In theory tuning of the velocity in the range given by v0 and vm, i.e. the velocity for a SAW on a free and metallized substrate, is possible. We have achieved up to 17.6 m/s (0.44 %) velocity tuning on 128degYX LiNbO3. A maximum velocity sensitivity of Deltav/v of 15times10-3/V and phase sensitivity of 700deg/V was measured. This is five orders of magnitude larger than values obtained for electrical field tuning.
{"title":"P0-13 Phase Velocity Control of Surface Acoustic Waves Based on Surface Shorting and Electrical Field Application Using MEMS Switches","authors":"J. Kuypers, M. Schmidt, S. Tanaka, M. Esashi","doi":"10.1109/ULTSYM.2007.310","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.310","url":null,"abstract":"We have investigated controlling the phase velocity of a surface acoustic wave (SAW) by a microelectromechanical switch fabricated on a high coupling piezoelectric substrate. The principle is based on the interaction of the evanescent surface potential of the SAW with the conductive switch. In theory tuning of the velocity in the range given by v0 and vm, i.e. the velocity for a SAW on a free and metallized substrate, is possible. We have achieved up to 17.6 m/s (0.44 %) velocity tuning on 128degYX LiNbO3. A maximum velocity sensitivity of Deltav/v of 15times10-3/V and phase sensitivity of 700deg/V was measured. This is five orders of magnitude larger than values obtained for electrical field tuning.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"19 1","pages":"1233-1238"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74876714","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}
Frequency spectra of multi-layer Al-AlN FBAR resonator are calculated. It is shown, that plurality of frequency spectra can be obtained by various combinations of quantities of layers and their thickness. Each spectrum is individual and can be used for remote identification similar to SAW tags.
{"title":"P1I-3 FBAR Multi-Layer Resonator for Remote Identification","authors":"V. I. Cherednick","doi":"10.1109/ULTSYM.2007.362","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.362","url":null,"abstract":"Frequency spectra of multi-layer Al-AlN FBAR resonator are calculated. It is shown, that plurality of frequency spectra can be obtained by various combinations of quantities of layers and their thickness. Each spectrum is individual and can be used for remote identification similar to SAW tags.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"56 1","pages":"1441-1443"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73033898","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}
Traditional focused transducers use multiple elements with individual delays, or a single element and lens to achieve focusing. These approaches involve significant cost, or acoustic losses respectively, and are not well suited to low-cost applications, for example disposable transducers. In contrast, zone plate transducers use the diffraction pattern formed by a variable excitation over the surface of a single element to achieve focusing. Although this results in an inexpensive focused transducer, the focusing performance degrades with broadband excitation, and contrast is limited. Additionally it is difficult to produce diffraction patterns with an extended focal zone. We have developed a successive projection algorithm to optimize the transducer pattern to overcome these limitations and meet desired focusing properties at several frequencies and ranges simultaneously. Within diffraction limits, this technique is shown to significantly outperform conventional zone plate transducers, in some cases reducing sidelobes by as much as 20 dB. Furthermore we show that the necessary transducer patterns can be produced using off-the-shelf PCB technology, and that within the limitations of our fabrication process, we are able to experimentally validate our algorithm.
{"title":"9C-4 Novel Method for Design and Fabrication of Single Piston Transducers for Extended Depth of Field","authors":"K. Owen, W. Walker","doi":"10.1109/ULTSYM.2007.203","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.203","url":null,"abstract":"Traditional focused transducers use multiple elements with individual delays, or a single element and lens to achieve focusing. These approaches involve significant cost, or acoustic losses respectively, and are not well suited to low-cost applications, for example disposable transducers. In contrast, zone plate transducers use the diffraction pattern formed by a variable excitation over the surface of a single element to achieve focusing. Although this results in an inexpensive focused transducer, the focusing performance degrades with broadband excitation, and contrast is limited. Additionally it is difficult to produce diffraction patterns with an extended focal zone. We have developed a successive projection algorithm to optimize the transducer pattern to overcome these limitations and meet desired focusing properties at several frequencies and ranges simultaneously. Within diffraction limits, this technique is shown to significantly outperform conventional zone plate transducers, in some cases reducing sidelobes by as much as 20 dB. Furthermore we show that the necessary transducer patterns can be produced using off-the-shelf PCB technology, and that within the limitations of our fabrication process, we are able to experimentally validate our algorithm.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"1 1","pages":"793-796"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73184547","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}
The operation of surface acoustic wave (SAW) tags at harmonic modes can relax lithography restriction from the frequency raise and archive a good power handling. In this paper a simulation tool for analyzing SAW tags operating at harmonic frequencies is developed. We extended a coupling of modes (COM) model to calculate their harmonic responses by integrating the quasi-static approximation. The considered SAW tags were decimal and had reflectors of single-electrode IDT, three-finger IDT and split-electrode IDT. Finally, some related experiments were implemented: the SAW tags were by micro-electro-mechanical system processes and measured via Network analyzer and a probe station. Experimental results, showing a good agreement with simulation results, prove the feasibility of the proposed simulation tool. Based on all results, we found that the 2nd harmonic of three-finger IDT and 3rd harmonic of split-electrode IDT are effective to achieve a higher operating frequency for SAW tags.
{"title":"P5H-3 A COM Analysis of SAW Tags Operating at Harmonic Frequencies","authors":"Yung-Yu Chen, Tsung-Tsong Wu, Kai-Ti Chang","doi":"10.1109/ULTSYM.2007.590","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.590","url":null,"abstract":"The operation of surface acoustic wave (SAW) tags at harmonic modes can relax lithography restriction from the frequency raise and archive a good power handling. In this paper a simulation tool for analyzing SAW tags operating at harmonic frequencies is developed. We extended a coupling of modes (COM) model to calculate their harmonic responses by integrating the quasi-static approximation. The considered SAW tags were decimal and had reflectors of single-electrode IDT, three-finger IDT and split-electrode IDT. Finally, some related experiments were implemented: the SAW tags were by micro-electro-mechanical system processes and measured via Network analyzer and a probe station. Experimental results, showing a good agreement with simulation results, prove the feasibility of the proposed simulation tool. Based on all results, we found that the 2nd harmonic of three-finger IDT and 3rd harmonic of split-electrode IDT are effective to achieve a higher operating frequency for SAW tags.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"1 1","pages":"2347-2350"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75301350","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}
A filter with aluminum nitride thin-film bulk acoustic resonators (FBAR) for the X-band was developed. The FBAR has an air gap beneath the resonator to isolate acoustically from a substrate, and is extremely thin to operate in the X-band. The FBAR has two structural features - a sacrificial layer to make the air gap was very thin in order to prevent the resonator from cracking on the edge of the air gap, and a resonator was deformed to dome shape by stresses of the films to keep the air gap. The fabricated FBAR operated successfully with a keff 2 of 6.40%, a resonance Q of 246, and anti-resonance Q of 462. The fabricated filter had a center frequency of 9.07 GHz, a fractional bandwidth of 3.1%, a minimum insertion loss of -1.7 dB, and an out-of-band rejection of -21 dB.
{"title":"12E-2 X-Band Filters Utilizing AlN Thin Film Bulk Acoustic Resonators","authors":"M. Hara, T. Yokoyama, M. Ueda, Y. Satoh","doi":"10.1109/ULTSYM.2007.291","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.291","url":null,"abstract":"A filter with aluminum nitride thin-film bulk acoustic resonators (FBAR) for the X-band was developed. The FBAR has an air gap beneath the resonator to isolate acoustically from a substrate, and is extremely thin to operate in the X-band. The FBAR has two structural features - a sacrificial layer to make the air gap was very thin in order to prevent the resonator from cracking on the edge of the air gap, and a resonator was deformed to dome shape by stresses of the films to keep the air gap. The fabricated FBAR operated successfully with a keff 2 of 6.40%, a resonance Q of 246, and anti-resonance Q of 462. The fabricated filter had a center frequency of 9.07 GHz, a fractional bandwidth of 3.1%, a minimum insertion loss of -1.7 dB, and an out-of-band rejection of -21 dB.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"67 1","pages":"1152-1155"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74325156","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}
C. Chandrana, N.A. Kharin, A. Nair, K. Waters, D. Vince, B. Kuban, G. Lockwood, S. Roy, A. Fleischman
Intravascular ultrasound (IVUS) imaging is increasingly employed to assist in selecting and evaluating therapeutic intervention. Recent work in IVUS backscatter analysis demonstrates the capability of IVUS to characterize specific lesions and identify plaques that lead to various clinical syndromes. Correct identification of plaque types depends on their structure, composition and sufficient image resolution (< 30 mum axially). Tissue harmonic imaging (THI) has shown promise to increase quality of IVUS. However, Current IVUS catheters, with unfocused transducers and narrow bandwidths, might not benefit from advantages due to harmonic imaging. Hence, we are developing miniature focused large bandwidth ultrasonic transducers with high resolutions and harmonic imaging capabilities.We made spherically focused broad bandwidth (120%) PVDF- TrFE transducers using MEMS techniques. We characterized the transducers. We also developed a method for multiple ultrasonic modalities using existing hardware and employing pulse-inversion techniques where a single transducer can be used to produce four modes of images. In this study, we obtained images of the coronary ostium in four imaging modes (Fundamental 20 MHz, Fundamental 40 MHz, Harmonic 40 MHz and Harmonic 80 MHz). We also excited our transducer with 40 MHz monocycle pulse for maximal axial resolution to generate standard mode images. Our standard mode images were compared to histology and commercial IVUS Systems. Axial resolutions with a monocycle pulse were typically less than 19 mum with a bandwidth of ~ 120 %. The lateral resolution characterization was done using a 1 mm transducer with an f-number 2.6. Harmonic signals showed better resolution compared to the fundamental signals. Ex vivo circumferential images of the human coronary ostium at F20, F40, H40 and H80 were acquired. The standard mode ultrasonic image of the human aorta using the MEMS transducer clearly displayed better delineation of the media compared to the existing commercial IVUS systems. When comparing the standard mode 40 MHz ultrasonic image to its histology, our ultrasonic image showed near histological resolution and identified various features in the histology. Such promising results suggest that the high resolution transducers with multi modality imaging capabilities can improve the clinical use of IVUS for cardiovascular diseases.
{"title":"P0-1 High Resolution Fundamental and Harmonic Imaging Using a MEMS Fabricated Ultrasonic Transducer","authors":"C. Chandrana, N.A. Kharin, A. Nair, K. Waters, D. Vince, B. Kuban, G. Lockwood, S. Roy, A. Fleischman","doi":"10.1109/ULTSYM.2007.298","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.298","url":null,"abstract":"Intravascular ultrasound (IVUS) imaging is increasingly employed to assist in selecting and evaluating therapeutic intervention. Recent work in IVUS backscatter analysis demonstrates the capability of IVUS to characterize specific lesions and identify plaques that lead to various clinical syndromes. Correct identification of plaque types depends on their structure, composition and sufficient image resolution (< 30 mum axially). Tissue harmonic imaging (THI) has shown promise to increase quality of IVUS. However, Current IVUS catheters, with unfocused transducers and narrow bandwidths, might not benefit from advantages due to harmonic imaging. Hence, we are developing miniature focused large bandwidth ultrasonic transducers with high resolutions and harmonic imaging capabilities.We made spherically focused broad bandwidth (120%) PVDF- TrFE transducers using MEMS techniques. We characterized the transducers. We also developed a method for multiple ultrasonic modalities using existing hardware and employing pulse-inversion techniques where a single transducer can be used to produce four modes of images. In this study, we obtained images of the coronary ostium in four imaging modes (Fundamental 20 MHz, Fundamental 40 MHz, Harmonic 40 MHz and Harmonic 80 MHz). We also excited our transducer with 40 MHz monocycle pulse for maximal axial resolution to generate standard mode images. Our standard mode images were compared to histology and commercial IVUS Systems. Axial resolutions with a monocycle pulse were typically less than 19 mum with a bandwidth of ~ 120 %. The lateral resolution characterization was done using a 1 mm transducer with an f-number 2.6. Harmonic signals showed better resolution compared to the fundamental signals. Ex vivo circumferential images of the human coronary ostium at F20, F40, H40 and H80 were acquired. The standard mode ultrasonic image of the human aorta using the MEMS transducer clearly displayed better delineation of the media compared to the existing commercial IVUS systems. When comparing the standard mode 40 MHz ultrasonic image to its histology, our ultrasonic image showed near histological resolution and identified various features in the histology. Such promising results suggest that the high resolution transducers with multi modality imaging capabilities can improve the clinical use of IVUS for cardiovascular diseases.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"28 1","pages":"1183-1187"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74332244","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}
We have previously described guidance of several interventional devices using a real time 3D (RT3D) ultrasound system with 3D color Doppler combined with the ColorMark technology. We then developed an analytical model for a vibrating needle to maximize the tip vibrations and improve the reliability and sensitivity of our technique. In this work, we use the analytical model and improved radiofrequency (RF) and color Doppler filters to detect two different vibrating devices in water tank experiments as well as in an in vivo canine experiment. An atrial septal puncture needle and an endomyocardial biopsy forceps, each vibrating at 1.3 kHz, were inserted into the vascular graft and were tracked using 3D color Doppler. Improved RF and wall filters increased the detected color Doppler sensitivity by 14 dB. In three simultaneous planes from the in vivo 3D scan, we identified both the septal puncture needle and the biopsy forceps within the right atrium using the 2.5 MHz probe. A display filter was used to suppress the unwanted flash artifact associated with physiological motion.
{"title":"10B-3 Vibrating Interventional Device Detection Using Real-Time 3D Color Doppler","authors":"M. Fronheiser, S. Idriss, P. Wolf, S.W. Smith","doi":"10.1109/ULTSYM.2007.222","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.222","url":null,"abstract":"We have previously described guidance of several interventional devices using a real time 3D (RT3D) ultrasound system with 3D color Doppler combined with the ColorMark technology. We then developed an analytical model for a vibrating needle to maximize the tip vibrations and improve the reliability and sensitivity of our technique. In this work, we use the analytical model and improved radiofrequency (RF) and color Doppler filters to detect two different vibrating devices in water tank experiments as well as in an in vivo canine experiment. An atrial septal puncture needle and an endomyocardial biopsy forceps, each vibrating at 1.3 kHz, were inserted into the vascular graft and were tracked using 3D color Doppler. Improved RF and wall filters increased the detected color Doppler sensitivity by 14 dB. In three simultaneous planes from the in vivo 3D scan, we identified both the septal puncture needle and the biopsy forceps within the right atrium using the 2.5 MHz probe. A display filter was used to suppress the unwanted flash artifact associated with physiological motion.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"1 1","pages":"868-871"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72551875","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}
C. Zuo, N. Sinha, M. Pisani, C.R. Perez, R. Mahameed, G. Piazza
This paper reports experimental results on a new class of single-chip multi-frequency channel-select filters based on self-coupled aluminum nitride (AlN) contour-mode piezoelectric resonators. For the first time, two-port AlN contour- mode resonators are connected in series and electrically coupled using their intrinsic capacitance to form multi-frequency (94 -271 MHz), narrow bandwidth (~ .3%), low insertion loss (~4 dB), high off-band rejection (~60 dB) and extremely linear (IIP3-110 dBm) channel-select filters. This novel technology enables multi-frequency, high-performance and small form factor filter arrays and makes a single-chip multi-band RF solution possible in the near future.
{"title":"12E-3 Channel-Select RF MEMS Filters Based on Self-Coupled AlN Contour-Mode Piezoelectric Resonators","authors":"C. Zuo, N. Sinha, M. Pisani, C.R. Perez, R. Mahameed, G. Piazza","doi":"10.1109/ULTSYM.2007.292","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.292","url":null,"abstract":"This paper reports experimental results on a new class of single-chip multi-frequency channel-select filters based on self-coupled aluminum nitride (AlN) contour-mode piezoelectric resonators. For the first time, two-port AlN contour- mode resonators are connected in series and electrically coupled using their intrinsic capacitance to form multi-frequency (94 -271 MHz), narrow bandwidth (~ .3%), low insertion loss (~4 dB), high off-band rejection (~60 dB) and extremely linear (IIP3-110 dBm) channel-select filters. This novel technology enables multi-frequency, high-performance and small form factor filter arrays and makes a single-chip multi-band RF solution possible in the near future.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"42 1","pages":"1156-1159"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72724791","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}
Very small SAW filters of the size 0.8 mm x 0.6 mm based on wafer-level packaging technology are fabricated and tested. Excellent electrical performance as well as robustness against humidity and mechanical stress are demonstrated. Complete devices are fabricated on a wafer, instead of bonding with a ceramic substrate or another wafer. A structure with a hollow space is built on the piezoelectric substrate by semiconductor processes in order to allow the surface acoustic waves to freely propagate without any loss. Either LGA or BGA type of terminals are available with the filter. It is demonstrated that the developed WLP SAW filters are suitable for use in high-performance RF front-end modules.
基于晶圆级封装技术,制造和测试了尺寸为0.8 mm x 0.6 mm的非常小的SAW滤波器。优异的电气性能以及抗湿度和机械应力的稳健性被证明。完整的器件是在晶圆上制造的,而不是与陶瓷衬底或另一个晶圆结合。为了使表面声波能无损耗地自由传播,采用半导体工艺在压电基板上建立了一个具有中空空间的结构。LGA或BGA类型的端子可与滤波器一起使用。实验结果表明,所开发的WLP SAW滤波器适用于高性能射频前端模块。
{"title":"2E-2 0806 SAW Filters Using Wafer Level Packaging Technology","authors":"T. Fukano, Y. Okubo, J. Nishii, I. Obara","doi":"10.1109/ULTSYM.2007.30","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.30","url":null,"abstract":"Very small SAW filters of the size 0.8 mm x 0.6 mm based on wafer-level packaging technology are fabricated and tested. Excellent electrical performance as well as robustness against humidity and mechanical stress are demonstrated. Complete devices are fabricated on a wafer, instead of bonding with a ceramic substrate or another wafer. A structure with a hollow space is built on the piezoelectric substrate by semiconductor processes in order to allow the surface acoustic waves to freely propagate without any loss. Either LGA or BGA type of terminals are available with the filter. It is demonstrated that the developed WLP SAW filters are suitable for use in high-performance RF front-end modules.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"10 1","pages":"68-71"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74402413","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}