2007 IEEE Ultrasonics Symposium Proceedings最新文献

{"title":"P3I-3 Wafer Level Chip Size Packaging of SAW Devices Using Low Temperature Sacrifice Process","authors":"K. Koh, T. Yamazaki, K. Hohkawa","doi":"10.1109/ULTSYM.2007.475","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.475","url":null,"abstract":"In this paper, we report a basic study on wafer level chip size packaging (WL-CSP) process of SAW devices using low temperature sacrifice process. We used the dry film photoresist as sacrifice layer because it has advantage such as low treating temperature (<120 degree), easily coating on the surface of wafer and easily to removal by organic solution. We proposed several processes using dry film photoresist for different purpose. We investigated various processing conditions and successfully fabricated a cavity with small size as active area of the SAW device. The experimental results confirmed feasibility of the dry film photoresist used in WL-CSP technology of SAW device.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"26 1","pages":"1890-1893"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74769508","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":"7C-6 Motion Artifact Reduction by ECG Gating in Ultrasound Induced Thermal Strain Imaging","authors":"K. Kim, S.-W. Huang, R. Olafsson, C. Jia, R. Witte, M. O’Donnell","doi":"10.1109/ULTSYM.2007.151","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.151","url":null,"abstract":"Cardiac motion related artifact in ultrasound induced thermal strain imaging (TSI) was reduced in-vitro and in-vivo using ECG gating. Tissue motion due to the heart beat is a major challenge for in-vivo TSI application, especially for cardiovascular systems. Temporal variation of the relative position between the transducer and the artery will induce decorrelation in speckle tracking. Tissue deformation produces mechanical strains directly. Thermal strains are equivalent to their motion-induced mechanical counterparts and are typically an order of magnitude smaller. Consequently, effective reduction of motion artifacts is critical for clinical use of TSI. Using ECG signals to trigger array firing, cardiac periodicity can be fully utilized to minimize motion artifacts, allowing thermal strains to accumulate over multiple cardiac cycles with little distortion. TSI gated by the lumen pressure signal on an artery phantom (rubber) connected to a pulsatile pumping system compares well with TSI when the phantom was immobile for the same heating/imaging sequences. An in-vivo test was performed on a rabbit femoral artery under local animal protocol. The animal's ECG gated a similar pulse sequence used for the phantom. The in-vivo temperature rise in the femoral arterial wall was also estimated. This estimation is well above the background noise in TSI due to speckle tracking error or/and any possible residual vibration. Breathing motion artifacts can be minimized in the clinic through a breath hold.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"14 1","pages":"581-584"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73155185","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":"6C-6 Qualitative Properties of an Entropy-Based Signal Detector","authors":"Michael S. Hughes, J. Marsh, K. Wallace, L. J. Thomas, G. Lanza, S. Wickline, J. McCarthy, B. Maurizi","doi":"10.1109/ULTSYM.2007.126","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.126","url":null,"abstract":"Detection of molecular epitopes associated with neo- vasculature in a growing tumor presents a unique challenge for ultrasonic clinical imaging systems. In this study, we attempt to solve the problem of detection of site-specific contrast through the use of signal receivers (i.e., mathematical operations that reduce an entire radio frequency (RF) waveform or a portion of it to a single number) based on information-theoretic quantities, such as Shannon Entropy (H), or its counterpart for continuous signal (Hf). These receivers appear to be sensitive to diffuse, low amplitude features of the signal that often are obscured by noise, or else lost in large specular echoes and, hence, not usually perceivable by a human observer. Qualitative and quantitative properties of the finite part, Hf, of the Shannon entropy of a continuous waveform f(t) in the continuum limit are derived in order to illuminate its use for waveform characterization.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"38 1","pages":"468-471"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73255643","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":"P4M-3 Experimental Characterization of Capacitive Micromachined Ultrasonic Transducers","authors":"S. Oleum, A. Atalar, H. Koymen, K. Oguz, M. N. Senlik","doi":"10.1109/ULTSYM.2007.536","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.536","url":null,"abstract":"In this paper, capacitive micromachined ultrasonic transducers are fabricated using a sacrificial surface micro- machining process. A testing procedure has been established in order to measure the absolute transmit and receive sensitivity spectra of the fabricated devices. The experiments are performed in oil. Pulse-echo experiments are performed and the results are compared to the pitch-catch measurements using calibrated transducers.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"78 1","pages":"2131-2134"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74187370","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":"P5A-1 A Method for Improved Standardization of In Vivo Calcaneal Time-Domain Speed-of-Sound Measurements","authors":"K. Wear","doi":"10.1109/ULTSYM.2007.543","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.543","url":null,"abstract":"Clinical SOS measurements exhibit a high degree of inter-system variability. Calcaneal SOS is usually computed from time-of-flight measurements of broadband ultrasound pulses that propagate through the foot. In order to minimize the effects of multi-path interference, many investigators measure time-of-flight from markers near the leading edge of the pulse. The calcaneus is a highly attenuating, highly inhomogeneous bone that distorts propagating ultrasound pulses via frequency- dependent attenuation, reverberation, dispersion, multiple scattering, and refraction. This pulse distortion can produce errors in leading-edge transit-time marker based SOS measurements. In this paper, an equation to predict dependence of time-domain SOS measurements on system parameters (center frequency and bandwidth), transit-time marker location, and bone properties (attenuation coefficient and thickness) is validated with through-transmission measurements in a bone- mimicking phantom and in 73 women in vivo, using a clinical bone sonometer. In order to test the utility of the formula for suppressing system dependence of SOS measurements, a wideband laboratory data acquisition system was used to make a second set of through-transmission measurements on the phantom. The compensation formula reduced system-dependent leading-edge transit-time marker based SOS measurements in the phantom from 41 m/s to 5 m/s and reduced transit-time marker related SOS variability in 73 women from 40 m/s to 10 m/s. The compensation formula can be used to improve standardization in bone sonometry.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"84 1","pages":"2159-2162"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72744754","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":"6D-2 MEMS-Enabled Miniaturized Particulate Matter Monitor Employing 1.6 GHz Aluminum Nitride Thin-Film Bulk Acoustic Wave Resonator (FBAR) and Thermophoretic Precipitator","authors":"J. Black, A. Elium, R. White, M. Apte, L. Gundel, R. Cambie","doi":"10.1109/ULTSYM.2007.128","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.128","url":null,"abstract":"We describe a miniaturized MEMS particulate matter (PM) monitor that employs the deposition of particulates from a sample stream onto a 1.6 GHz piezoelectric thin-film bulk acoustic wave resonator (FBAR) by means of thermophoresis, and determination of the mass deposited by measuring the resonant frequency shift of a Pierce oscillator. Real-time measurements made in an environmental chamber over several weeks and during a week-long field study in a residence showed excellent correlation with the responses of other commercial aerosol instruments. An added mass of 1 pg could be resolved with the sensor, and the level of detection was 18 mug / m3. The monitor weighs 114 g, has a volume of approximately 245 cm3, consumes less than 100 mW, and would cost less than $100 USD in small quantities. Efforts to further miniaturize the sensor and integrate it with a cell-phone are described.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"42 1","pages":"476-479"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72781195","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":"P1J-1 Optimized Piezoelectric Sol-Gel Composite Films for High Frequency Ultrasonic Transducers","authors":"A. Bardaine, P. Boy, P. Belleville, O. Acher, F. Levassort","doi":"10.1109/ULTSYM.2007.364","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.364","url":null,"abstract":"High frequency piezoelectric films were prepared using the composite sol-gel technique, by mixing PZT sol and laboratory-made powders, free-cracked thick films were deposited by dip-coating on silicon, alumina and porous PZT substrates. Only 3 composite layers and few final infiltrations were used to prepare 40 mum thick films. Reproducible electromechanical properties, i.e. thickness coupling coefficients around 40%, were obtained after a poling at 15V mum in an oil bath at 170degC. A pulse echo response was measured with a 35 mum thick film deposited on a porous PZT substrate. The corresponding characteristics are an axial resolution of 45 mum (with a bandwidth at 80*%) at -6dB and a center frequency of 20 MHz. These results showed that the composite sol-gel process is a good candidate to produce piezoelectric films with a thickness of few tens of microns with a minimization of fabrication steps.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"25 1","pages":"1448-1451"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79122049","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":"8C-5 Full 3D Inversion of the Viscoelasticity Wave Propagation Problem for 3D Ultrasound Elastography in Breast Cancer Diagnosis","authors":"M. Muller, J. Gennisson, T. Deffieux, R. Sinkus, P. Annic, G. Montaldo, M. Tanter, M. Fink","doi":"10.1109/ULTSYM.2007.174","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.174","url":null,"abstract":"An experimental 3D ultrasound elastography setup has been designed for breast cancer diagnosis improvement. 3D elastography assessment is generally based on the combination of adjacent 2D elasticity maps, obtained through simple 2D inverse problem resolution. Meanwhile, 3D sonoelastography is based on simple inversion approaches to the viscoelasticity problem. The system presented here is based on the resolution of a full 3D inverse problem, from the complete ultrasound-based measurement of the three components of the 3D displacement field. The 3D information considerably improves the accuracy and reliability of the quantitative measurements and circumvents the operator-dependent aspects of 2D echography diagnosis. The combination of 3D echography and elastography could be a very promising tool for in vivo breast cancer diagnosis. The X-ray system of a commercial mammographic bed was replaced by an ultrasound device. Shear waves were generated using a low frequency vibrator. Resulting displacements in tissues were imaged using an echographic probe moving stepwise around the breast. Advanced techniques such as compounding echographic probe sub-apertures and 2D vector Doppler algorithms were used to assess the three components of the displacement. Shear elasticity, viscosity and anisotropy were quantified using a 3D elastic properties reconstruction algorithm. A 3D finite difference simulation algorithm based on the viscoelastic propagation equation was used to model the 3D forward problem, and validate the inverse reconstruction algorithm. Simulated displacements in a numerical phantom were used as inputs for the inverse problem resolution, allowing the reconstruction of elastic properties similar to that of the numerical phantom. Similarly to MR-elastography, the inverse problem was solved in the Fourier domain. However, overcoming the data acquisition limitations of MR-elastography, the ultrasound-based approach enables the implementation of frequency compound methods based on averaging the data at different shear frequencies, increasing the measurement accuracy. In the present study, the experimental setup was optimized using numerical simulations and validated in vitro. In vitro experiments were conducted on a calibrated phantom exhibiting harder inclusions. Its 3D elastic properties were reconstructed and found consistent with that given by the manufacturer. This study allowed the numerical and experimental validation of the complete 3D elastography protocol.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"6 1","pages":"672-675"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79277005","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":"3B-4 Therapeutic Potential Metric for Diagnostic Transducers","authors":"K. Frinkley, S. Rosenzweig, K. Nightingale","doi":"10.1109/ULTSYM.2007.42","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.42","url":null,"abstract":"The goal of this work is to develop a 'therapeutic potential' metric and experimental protocol to define the expected efficacy of commercial, diagnostic transducers for thermal therapy. Temperature rises at the transducer face were measured using thin-film thermocouples (TFTs) on a tissue mimicking phantom for sequences with moderate acoustic output as an indicator of the risk of damage to the transducer during therapeutic applications. Several measurements were then taken to evaluate the focal heating of the transducer and compared with thermocouple measurements. The acoustic power was measured near the surface of the transducer. Spatial peak and spatial average intensities were measured in the focal plane at low system voltages to avoid nonlinear effects. Finally, ARFI imaging displacements within plusmn25% of the focus in a tissue-mimicking phantom were evaluated. Four transducers were compared using these protocols (two curvilinear arrays, one phased array, and one two-dimensional array). Without focal gain considerations, acoustic power is an inaccurate predictor of focal heating. ARFI displacement cannot easily be used to estimate focal heating, primarily due to confounding mechanical phenomena. After normalizing each measurement by the ultrasound system input, measurement device properties, focal configuration, and temporal properties, the therapeutic potential metric can most efficiently and accurately be defined by maximizing the ratio of the spatial peak intensity at the focus to the heating at the transducer face. The ratio of spatial average intensity or temperature at the focus to surface temperature can be used as alternative or additional metrics. The ID, phased array was determined to have the highest therapeutic potential for focal depths near 3.75 cm.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"39 1","pages":"116-119"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84449890","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":"P6C-7 Ultrasound RF Time Series for Detection of Prostate Cancer: Feature Selection and Frame Rate Analysis","authors":"Mehdi Moradi, P. Abolmaesumi, R. Siemens, E. Sauerbrei, P. Isotalo, A. Boag, P. Mousavi","doi":"10.1109/ULTSYM.2007.627","DOIUrl":"https://doi.org/10.1109/ULTSYM.2007.627","url":null,"abstract":"This paper provides the recent results of in-vitro clinical studies to evaluate the performance of a tissue typing method, based on ultrasound RF time series, for detection of prostate cancer. In our approach, we continuously record RF echo signals backscattered from tissue, while the imaging probe and the tissue are stationary in position. The continuously recorded frames generate a time series of echo values for each spatial sample of RF signals. We extract the fractal dimension, and six spectral features from the RF time series and use them with neural networks for tissue typing. We analyze the performance of this method in detecting prostate cancer in 16 patients and demonstrate that a subset of five parameters selected from the proposed features is optimal for the diagnosis. We also study the performance of the extracted features at various frame rates and show that 22 frames per second is sufficient for efficient cancer detection with an area under ROC curve of 0.89.","PeriodicalId":6355,"journal":{"name":"2007 IEEE Ultrasonics Symposium Proceedings","volume":"59 Pt A 1","pages":"2493-2496"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84556948","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}