Non-invasive high-resolution acoustic microscopy technique using embedded nanostructures

2007 ◽  
Vol 1019 ◽  
Author(s):  
Daniel Wulin ◽  
Shriram Ramanathan

AbstractAn opto-acoustic system capable of operating at frequencies greater than 1 GHz with novel biological applications is proposed for the first time. Metallic spheres with radii on the order of hundreds of nanometers dispersed inside a bio-matrix can be used to generate in-situ ultra-high frequency acoustic waves whose normal mode frequencies can be calculated using Lamb's theory for acoustic oscillations of elastic spheres. The frequency and amplitude of the resulting acoustic waves can be related to the physical properties of the metallic spheres and the surrounding bio-matrix: the acoustic waves produced by the metallic spheres are well-suited to high resolution acoustic imaging. We anticipate that our approach will open up new nanoscale techniques to study cells non-invasively.

2006 ◽  
Vol 21 (5) ◽  
pp. 1204-1208 ◽  
Author(s):  
Shriram Ramanathan ◽  
David G. Cahill

Non-destructive investigation of buried interfaces at high-resolution is critical for integrated circuit and advanced packaging research and development. In this letter, we present a novel non-contact microscopy technique using ultrahigh frequency (GHz range) longitudinal acoustic pulses to form images of interfaces and layers buried deep inside a silicon device. This method overcomes fundamental limitations of conventional scanning acoustic microscopy by directly generating and detecting the acoustic waves on the surface of the sample using an ultrafast pump-probe optical technique. We demonstrate our method by imaging copper lines buried beneath a 6-μm silicon wafer; the lateral spatial resolution of 3 μm is limited by the laser spot size. In addition to the high lateral spatial resolution, the technique has picosecond (ps) time resolution and therefore will enable imaging individual interconnect layers in multi-layer stacked devices.


2018 ◽  
Vol 78 (05) ◽  
pp. 493-498 ◽  
Author(s):  
Rüdiger Schulz-Wendtland ◽  
Caroline Preuss ◽  
Peter Fasching ◽  
Christian Loehberg ◽  
Michael Lux ◽  
...  

Abstract Introduction For decades, conventional galactography was the only imaging technique capable of showing the mammary ducts. Today, diagnosis is based on a multimodal concept which combines high-resolution ultrasound with magnetic resonance (MR) mammography and ductoscopy/galactoscopy and has a sensitivity and specificity of up to 95%. This study used tomosynthesis in galactography for the first time and compared the synthetic digital 2D full-field mammograms generated with this technique with the images created using the established method of ductal sonography. Both methods should be able to detect invasive breast cancers and their precursors such as ductal carcinoma in situ (DCIS) as well as being able to identify benign findings. Material and Methods Five patients with pathological nipple discharge were examined using ductal sonography, contrast-enhanced 3D galactography with tomosynthesis and the synthetic digital 2D full-field mammograms generated with the latter method. Evaluation of the images created with the different imaging modalities was done by three investigators with varying levels of experience with complementary breast diagnostics (1, 5 and 15 years), and their evaluations were compared with the histological findings. Results All 3 investigators independently evaluated the images created with ductal sonography, contrast-enhanced 3D galactography with tomosynthesis, and generated synthetic digital 2D full-field mammograms. Their evaluations were compared with the histopathological assessment of the surgical specimens resected from the 5 patients. There was 1 case of invasive breast cancer, 2 cases with ductal carcinoma in situ and 2 cases with benign findings. All 3 investigators made more mistakes when they used the standard imaging technique of ductal sonography to diagnose suspicious lesions than when they used contrast-enhanced galactography with tomosynthesis and the generated synthetic digital 2D full-field mammograms. Conclusion This is the first time breast tomosynthesis was used in galactography (galactomosynthesis) to create digital 3-dimensional images of suspicious findings. When used together with the generated synthetic digital 2D full-field mammograms, it could be a useful complementary procedure for the diagnosis of breast anomalies and could herald a renaissance of this method. Compared with high-resolution ductal ultrasound, the investigators achieved better results with contrast-enhanced galactography using tomosynthesis and the generated synthetic digital 2D full-field mammograms, as confirmed by histopathological findings.


2016 ◽  
Vol 140 (4) ◽  
pp. 3245-3245 ◽  
Author(s):  
Naohiro Hozumi ◽  
Kyoichi Takanashi ◽  
Mamoru Washiya ◽  
Sachiko Yoshida ◽  
Kazuto Kobayashi ◽  
...  

2004 ◽  
Vol 22 (6) ◽  
pp. 2033-2036
Author(s):  
S. P. Gupta ◽  
R. Sekar ◽  
Y. B. Acharya

Abstract. In situ probe measurements of plasma parameters were carried out on 18 and 20 November 1999 from Sriharikota, India, a low-latitude rocket launching station to investigate the effect of a Leonid meteor storm. Results obtained on plasma waves using a high frequency Langmuir probe are discussed. The characteristics of the sub-meter scale size plasma waves observed for the first time during Leonid meteor storm are presented. Based on the results obtained from both the rocket flights and comparison with the results obtained from previous rocket flights from the same location, it appears these sub-meter waves are associated with intense meteoric activity. A possible mechanism based on the dependence of the meteoric activity and its limitations are discussed.


2015 ◽  
Vol 70 ◽  
pp. 191-194 ◽  
Author(s):  
G. Zaz ◽  
A. Dekkious ◽  
P.A. Meignen ◽  
Y. Calzavara ◽  
E. Le Clézio ◽  
...  

2000 ◽  
Vol 6 (1) ◽  
pp. 59-67
Author(s):  
Theodore E. Matikas

Abstract A new acoustic microscopy method was developed for providing near-surface elastic property mapping of a material. This method has a number of advantages over the traditional V(z) technique. First, it enables one to perform measurements in an automated mode that only requires user intervention in the setup phase. This automated mode makes it feasible to obtain quantitative microscopy images of the elastic property over an area on the material being tested. Also, it only requires a conventional ultrasonic system operating in pulsed mode for collecting the data, rather than a specialized tone-burst system, which is needed in the traditional quantitative scanning acoustic microscopy technique. Finally, unlike the traditional method, the new experimental process does not require calibration of the systems electronics or additional reference data taken under hard-to-duplicate identical conditions from a material that does not exhibit surface acoustic waves.


1999 ◽  
Vol 81 (3) ◽  
pp. 520-527 ◽  
Author(s):  
G J Czarnota ◽  
M C Kolios ◽  
J Abraham ◽  
M Portnoy ◽  
F P Ottensmeyer ◽  
...  

2007 ◽  
Vol 26-28 ◽  
pp. 1199-1202
Author(s):  
Se Ahn Song ◽  
Wei Zhang ◽  
Hong Sik Jeong ◽  
Jin Gyu Kim ◽  
Youn Joong Kim

Phase transformation and crystal growth behavior of Ge2Sb2Te5 were investigated systematically by means of in situ heating (from room temperature to 500 oC) of amorphous Ge2Sb2Te5 alloy in a high voltage electron microscope with real-time monitoring. Large-scale crystallization occurred to amorphous Ge2Sb2Te5 around 200 oC. Large crystal growth developed on heating from 200 oC to 400 oC, and single crystalline grains grew up to 150 nm. Eventually the onset of partial melting of thin Ge2Sb2Te5 foil was at 500 oC and liquid Ge2Sb2Te5 was observed for the first time by high-resolution transmission electron microscopy. Hexagonal Ge2Sb2Te5 phase remains after a subsequent cooling.


Sign in / Sign up

Export Citation Format

Share Document