Mechanical properties of ceramic surfaces such as hard- ness, indentation fracture toughness, and wear resistance are largely influenced by the behavior of small flaws and defects, such as micro- cracks, delaminations, voids, and inclusion located beneath the sur- face. Acoustic microscopy is particularly suited to study this phenom- enon because it can image microscopic subsurface features without sectioning. Furthermore, it has been revealed that the velocity and at- tenuation of the leaky surface wave can be measured; these are ex- pected to have close correlation with the mechanical properties of ma- terials. New results on the nondestructive observation of subsurface cracks of Si,N, and ZrO, and delamination of TIN coatings introduced by Vickers indentation or sliding contacts are presented. The mecha- nism of delamination and wear of these materials is discussed. It is shown that the velocity and attenuation of the leaky surface wave of TIN coatings and sintered AlzOn actually have close correlation with the hardness and wear resistance of these materials. The reason for these correlations is also discussed.
{"title":"Acoustic Microscopy of Ceramic Surfaces","authors":"K. Yamanaka, Y. Enomoto, Y. Tsuya","doi":"10.1109/T-SU.1985.31597","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31597","url":null,"abstract":"Mechanical properties of ceramic surfaces such as hard- ness, indentation fracture toughness, and wear resistance are largely influenced by the behavior of small flaws and defects, such as micro- cracks, delaminations, voids, and inclusion located beneath the sur- face. Acoustic microscopy is particularly suited to study this phenom- enon because it can image microscopic subsurface features without sectioning. Furthermore, it has been revealed that the velocity and at- tenuation of the leaky surface wave can be measured; these are ex- pected to have close correlation with the mechanical properties of ma- terials. New results on the nondestructive observation of subsurface cracks of Si,N, and ZrO, and delamination of TIN coatings introduced by Vickers indentation or sliding contacts are presented. The mecha- nism of delamination and wear of these materials is discussed. It is shown that the velocity and attenuation of the leaky surface wave of TIN coatings and sintered AlzOn actually have close correlation with the hardness and wear resistance of these materials. The reason for these correlations is also discussed.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"377 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122049769","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}
Abstmct-The ability to measure elastic properties of materials and layered structures nondestructively on a microscopic scale gives rise to a new field of metrology via the reflection acoustic microscope. Acoustic micro-metrology accomplishes this task via the acoustic material signature (AMS), which is obtained from planar and curved surface specimens alike. The AMS constitutes a unique function that arises from interference of elastic propagating modes. These are simultaneously and coherently excited in the wide-angle lens ensembles that distinguish the acoustic microscope from other forms of ultrasonic pulse-echo systems. Several potential applications taken from diverse fields are described with experimental case studies. Examples of both materials and layered structures are described. Distinguishing features of different crystal orientations of single crystals may be readily detected. It is shown that the film thickness measurement of a wide variety of opaque materials is readily accomplished nondestructively and without a step. Machining damage in a Be surface may also be determined nondestructively. The AMS limitations imposed by frequency and material combinations, as presently viewed, are treated in the concluding section.
{"title":"Acoustic Micro-Metrology","authors":"R. D. Weglein","doi":"10.1109/T-SU.1985.31588","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31588","url":null,"abstract":"Abstmct-The ability to measure elastic properties of materials and layered structures nondestructively on a microscopic scale gives rise to a new field of metrology via the reflection acoustic microscope. Acoustic micro-metrology accomplishes this task via the acoustic material signature (AMS), which is obtained from planar and curved surface specimens alike. The AMS constitutes a unique function that arises from interference of elastic propagating modes. These are simultaneously and coherently excited in the wide-angle lens ensembles that distinguish the acoustic microscope from other forms of ultrasonic pulse-echo systems. Several potential applications taken from diverse fields are described with experimental case studies. Examples of both materials and layered structures are described. Distinguishing features of different crystal orientations of single crystals may be readily detected. It is shown that the film thickness measurement of a wide variety of opaque materials is readily accomplished nondestructively and without a step. Machining damage in a Be surface may also be determined nondestructively. The AMS limitations imposed by frequency and material combinations, as presently viewed, are treated in the concluding section.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127624975","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}
Abstmct-A scanning acoustic microscope operating in the frequency range 0.1 - L GHz has been developed. The acoustic micrographs obtained have clearly demonstrated that this device can be used nondestructively to observe spike defects at the edge of the local oxidation of silicon structures in semiconductor devices and hydrogenion-doped regions in silicon crystals. The acoustic data have been compared with results obtained through the scanning electron microscope and the optical microscope. ICROANALYSIS techniques used to measure and examine microscopic regions in materials with highfrequency ultrasound waves have recently received a great deal of attention as a new and highly promising means for measurement and observation. Typical of these new methods is the mechanical scanning acoustic microscope developed by Professor C. F. Quate at Stanford University in 1973 [l]. This device directs a narrow focused acoustic beam at a specimen being scanned two-dimensionally, and detects acoustic waves that are reflected from or transmitted through the specimen to obtain a two-dimensional image. The image contrast obtained reflects changes in the mechanical properties of materials in the specimen, such as elasticity, density, and viscosity. Applications of the acoustic microscope include, for example, fault detection in materials, the examination of semiconductor devices, and materials evaluation using surface acoustic waves [2]-161. In this paper we report the results of studies conducted on spike defects that arise in isolation regions between elements in semiconductor devices and regions bombarded by hydrogen ions on silicon substrates. 11. CONSTRUCTION OF THE ACOUSTIC MICROSCOPE The operating principles and construction of acoustic microscopes in general have already been described in a number of papers and will be omitted here. We intend to discuss here only several specific features particular to our reflection scanning acoustic microscope. The most important technical problems that had to solved during development of this device were the development of a process for forming high-performance piezoelectric film; a process for fabricating microspherical
摘要研制了一种工作频率为0.1 ~ L GHz的扫描声显微镜。所获得的声学显微照片清楚地表明，该装置可以无损地观察半导体器件中硅结构局部氧化边缘的尖峰缺陷和硅晶体中氢掺杂区域。并将声学数据与扫描电镜和光学显微镜所得结果进行了比较。使用高频超声波测量和检查材料微观区域的显微分析技术作为一种新的、极具前景的测量和观察手段，最近受到了广泛的关注。这些新方法的典型代表是1973年斯坦福大学C. F. Quate教授开发的机械扫描声学显微镜[1]。该装置将窄聚焦声束对准被二维扫描的样品，并检测从样品反射或透射的声波，以获得二维图像。获得的图像对比度反映了试样中材料力学性能的变化，如弹性、密度和粘度。声学显微镜的应用包括，例如，材料中的故障检测，半导体器件的检查，以及使用表面声波[2]-161对材料进行评估。在本文中，我们报告了对半导体器件中元件之间的隔离区域和硅衬底上氢离子轰击区域中产生的尖峰缺陷的研究结果。11. 声学显微镜的构造声学显微镜的工作原理和构造一般已经在许多论文中描述过，在这里略去。我们打算在这里只讨论我们的反射扫描声显微镜特有的几个特点。在研制过程中需要解决的最重要的技术问题是高性能压电薄膜的形成工艺的开发;一种制造微球面的方法
{"title":"An Acoustic Microscope for Subsurface Defect Characterization","authors":"I. Ishikawa, H. Kanda, K. Katakura","doi":"10.1109/T-SU.1985.31599","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31599","url":null,"abstract":"Abstmct-A scanning acoustic microscope operating in the frequency range 0.1 - L GHz has been developed. The acoustic micrographs obtained have clearly demonstrated that this device can be used nondestructively to observe spike defects at the edge of the local oxidation of silicon structures in semiconductor devices and hydrogenion-doped regions in silicon crystals. The acoustic data have been compared with results obtained through the scanning electron microscope and the optical microscope. ICROANALYSIS techniques used to measure and examine microscopic regions in materials with highfrequency ultrasound waves have recently received a great deal of attention as a new and highly promising means for measurement and observation. Typical of these new methods is the mechanical scanning acoustic microscope developed by Professor C. F. Quate at Stanford University in 1973 [l]. This device directs a narrow focused acoustic beam at a specimen being scanned two-dimensionally, and detects acoustic waves that are reflected from or transmitted through the specimen to obtain a two-dimensional image. The image contrast obtained reflects changes in the mechanical properties of materials in the specimen, such as elasticity, density, and viscosity. Applications of the acoustic microscope include, for example, fault detection in materials, the examination of semiconductor devices, and materials evaluation using surface acoustic waves [2]-161. In this paper we report the results of studies conducted on spike defects that arise in isolation regions between elements in semiconductor devices and regions bombarded by hydrogen ions on silicon substrates. 11. CONSTRUCTION OF THE ACOUSTIC MICROSCOPE The operating principles and construction of acoustic microscopes in general have already been described in a number of papers and will be omitted here. We intend to discuss here only several specific features particular to our reflection scanning acoustic microscope. The most important technical problems that had to solved during development of this device were the development of a process for forming high-performance piezoelectric film; a process for fabricating microspherical","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132574990","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}
Although the technique of scanning acoustic microscopy was introduced more than a decade ago, there still is a general lack of wide-spread applications research due to the limited number of instru- ments worldwide. To enlarge the spectrum of applications, this contri- bution presents selected results of work in materials science (ceramics, single crystals, polymers, thin ams, and integrated circuits) and biol- ogy (living cells, mucous coats, and cuticle structures). and an opening angle of 100" are used. The broadband design of the matching network and transducer and anti- reflection coating enables the frequency range to be cov- ered by two acoustic objectives, operating from 0.8 to 1.3 and 1.3 to 2.0 GHz, respectively. The x- and y-scanning is performed by electromagnetic coil systems driving the objective in a raster mode (x-scanning frequency locked
{"title":"Applications of Scanning Acoustic Microscopy - Survey and New Aspects","authors":"M. Hoppe, J. Bereiter-Hahn","doi":"10.1109/T-SU.1985.31595","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31595","url":null,"abstract":"Although the technique of scanning acoustic microscopy was introduced more than a decade ago, there still is a general lack of wide-spread applications research due to the limited number of instru- ments worldwide. To enlarge the spectrum of applications, this contri- bution presents selected results of work in materials science (ceramics, single crystals, polymers, thin ams, and integrated circuits) and biol- ogy (living cells, mucous coats, and cuticle structures). and an opening angle of 100\" are used. The broadband design of the matching network and transducer and anti- reflection coating enables the frequency range to be cov- ered by two acoustic objectives, operating from 0.8 to 1.3 and 1.3 to 2.0 GHz, respectively. The x- and y-scanning is performed by electromagnetic coil systems driving the objective in a raster mode (x-scanning frequency locked","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131661809","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}
Abstmcl-Acoustic microscopy has now made it possible to characterize biological materials on the microscopic level ultrasonically. The importance of the environmental conditions of the material being examined on its acoustic properties is demonstrated. Mammalian tendon threads (on the order of 150 pm in diameter) were examined with the scanning laser acoustic microscope while varying the media in which they were bathed. A relation between the osmolarity of the reference solution in which the tendon is bathed and the speed of sound of the thread under examination is suggested.
{"title":"Speed of Sound in Mammalian Tendon Threads Using Various Reference Media","authors":"C. A. Edwards, W. O’Brien","doi":"10.1109/T-SU.1985.31602","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31602","url":null,"abstract":"Abstmcl-Acoustic microscopy has now made it possible to characterize biological materials on the microscopic level ultrasonically. The importance of the environmental conditions of the material being examined on its acoustic properties is demonstrated. Mammalian tendon threads (on the order of 150 pm in diameter) were examined with the scanning laser acoustic microscope while varying the media in which they were bathed. A relation between the osmolarity of the reference solution in which the tendon is bathed and the speed of sound of the thread under examination is suggested.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"141 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125022299","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}
Abstmt-The resolution of the acoustic microscope is presently limited by the sound wavelength in the coupling fluid between the lens and sample. Cryogenic fluids offers two advantages over room temperature fluids for use in acoustic microscopy: low sound speed and low acoustic attenuation. Liquid nitrogen, argon, and helium have been used for microscopy, and they are all described. In liquid nitrogen and liquid argon, images have been obtained at frequencies as high as 2.8 GHz with a corresponding wavelength of 3000 A . A nonlinear effect was discovered in these liquids (as well as water) that improves the resolution of the microscope beyond the linear diffraction limit. Liquid helium emerges as the “ultimate” fluid for high-resolution acoustic microscopy because of its near zero acoustic attenuation at very low temperatures. Operating at temperatures less than 0.2 K, imaging with 300-A wavelength sound has been achieved. Applications include detection of thermal phonon emission from surfaces and general purpose high-resolution imaging with excellent sensitivity to slight topographical features.
{"title":"Low-Temperature Acoustic Microscopy","authors":"J. Foster, D. Rugar","doi":"10.1109/T-SU.1985.31581","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31581","url":null,"abstract":"Abstmt-The resolution of the acoustic microscope is presently limited by the sound wavelength in the coupling fluid between the lens and sample. Cryogenic fluids offers two advantages over room temperature fluids for use in acoustic microscopy: low sound speed and low acoustic attenuation. Liquid nitrogen, argon, and helium have been used for microscopy, and they are all described. In liquid nitrogen and liquid argon, images have been obtained at frequencies as high as 2.8 GHz with a corresponding wavelength of 3000 A . A nonlinear effect was discovered in these liquids (as well as water) that improves the resolution of the microscope beyond the linear diffraction limit. Liquid helium emerges as the “ultimate” fluid for high-resolution acoustic microscopy because of its near zero acoustic attenuation at very low temperatures. Operating at temperatures less than 0.2 K, imaging with 300-A wavelength sound has been achieved. Applications include detection of thermal phonon emission from surfaces and general purpose high-resolution imaging with excellent sensitivity to slight topographical features.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127984603","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}
By absorption of modulated optical power, a thermal wave is generated that interacts with thermal discontinuities. Imaging with scanned local thermal-wave probing is suited for non-contacting and non-destructive inspection of thermal structures in solids.
{"title":"Imaging with Optically Generated Thermal Waves","authors":"G. Busse","doi":"10.1098/rsta.1986.0109","DOIUrl":"https://doi.org/10.1098/rsta.1986.0109","url":null,"abstract":"By absorption of modulated optical power, a thermal wave is generated that interacts with thermal discontinuities. Imaging with scanned local thermal-wave probing is suited for non-contacting and non-destructive inspection of thermal structures in solids.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130417495","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 basic principles of surface-acoustic.,wave pulse compression acoustic microscopy is described and demonstrated by re- sults obtained at 60 and 750 MHz. A theoretical analysis discusses the behavior of such a system in terms of the required signal processing and the attainable imaging resolution. advantageous. At sufficiently high intensities, the imaging of the microscope will be affected by harmonic genera- tion, sometimes beneficially (g) but more usually in the sense of a large increase in effective attenuation loss (lo). It is clear that we can choose to use extended coded pulses to reduce the intensity at a constant illumination energy and hence the incidence of harmonic effects. We will describe the principles of operation of a pulse- compression microscope, based on surface acoustic wave (SAW) generated chirp pulses and illustrate the advan- tages of such a system by means of results from test sam- ples. A range of micrographs obtained at 60 MHz from metal-metal and metal-ceramic bonds with a processing gain of 17 dB is presented. At higher frequencies, the fre- quency-dependent attenuation in the coupling liquid im- poses two fundamental limitations on the performance of the pulse compression microscope: 1) reduction in the processing gain and 2) reduction in the imaging resolu- tion. Analysis shows, however, that even at high frequen- cies there can be a considerable advantage in using pulse compression. Experimental results at 750 MHz with a chirp bandwidth of 150 MHz have been obtained. We will show that the effective attainable resolution with such a coherent broadband system is in accord with a simple in- tuitive concept, based on monochromatic excitation, at a suitable averaged frequency. The reduction in processing gain due to loss dispersion, which we will calculate, is of course related to the partic- ular choice of coded pulse. However, the loss of resolution is a phenomenon that depends primarily on the spectrum of the pulse; for a pulse of a given spectral width one would not expect any significant differences between the effective resolution using a chirp or a rectangular RF pulse.
{"title":"Pulse Compression Acoustic Microscopy Using SAW Filters","authors":"M. Nikoonahad, Guang-Qi Yue, E. Ash","doi":"10.1109/T-SU.1985.31582","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31582","url":null,"abstract":"The basic principles of surface-acoustic.,wave pulse compression acoustic microscopy is described and demonstrated by re- sults obtained at 60 and 750 MHz. A theoretical analysis discusses the behavior of such a system in terms of the required signal processing and the attainable imaging resolution. advantageous. At sufficiently high intensities, the imaging of the microscope will be affected by harmonic genera- tion, sometimes beneficially (g) but more usually in the sense of a large increase in effective attenuation loss (lo). It is clear that we can choose to use extended coded pulses to reduce the intensity at a constant illumination energy and hence the incidence of harmonic effects. We will describe the principles of operation of a pulse- compression microscope, based on surface acoustic wave (SAW) generated chirp pulses and illustrate the advan- tages of such a system by means of results from test sam- ples. A range of micrographs obtained at 60 MHz from metal-metal and metal-ceramic bonds with a processing gain of 17 dB is presented. At higher frequencies, the fre- quency-dependent attenuation in the coupling liquid im- poses two fundamental limitations on the performance of the pulse compression microscope: 1) reduction in the processing gain and 2) reduction in the imaging resolu- tion. Analysis shows, however, that even at high frequen- cies there can be a considerable advantage in using pulse compression. Experimental results at 750 MHz with a chirp bandwidth of 150 MHz have been obtained. We will show that the effective attainable resolution with such a coherent broadband system is in accord with a simple in- tuitive concept, based on monochromatic excitation, at a suitable averaged frequency. The reduction in processing gain due to loss dispersion, which we will calculate, is of course related to the partic- ular choice of coded pulse. However, the loss of resolution is a phenomenon that depends primarily on the spectrum of the pulse; for a pulse of a given spectral width one would not expect any significant differences between the effective resolution using a chirp or a rectangular RF pulse.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127435944","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}
Absrmcf-There has been a lack of an accurate procedure for the measurement of an attenuation coefficient for biological tissues at 100 MHz with the scanning laser acoustic microscope (SLAM). The solution to this problem has been approached with two general schemes. One involved a calibrated look-up table, and the other utilized the measurement of insertion loss. For the latter a procedure has been developed and verified using known biological solutions. The insertion loss procedure yields an attenuation coefficient uncertainty to within five percent, a dynamic range from 4 to 28 dB/mm. and an insertion loss sensitivity of 0.2 dB. N IMPORTANT tissue characterization property is the ultrasonic attenuation coefficient, which is the decrease in energy of the sound wave when it propagates through a material. The attenuation includes absorption and scattering. Absorption represents the loss of energy into heat within the specimen. Scattering is a redirection of the energy due to the inhomogeneities of the specimen and includes reflection, refraction, and diffraction. The scanning laser acoustic microscope (SLAM) is a useful tool for providing at 100 MHz, the ultrasonic attenuation coefficient of tissue. A number of techniques have been developed to perform this measurement with the SLAM, and this report details and evaluates these techniques. Details of ultrasonic velocity measurements are found in companion papers [l], [2].
{"title":"Attenuation Coefficient Measurement Technique at 100 MHz with the Scanning Laser Acoustic Microscope","authors":"K. Tervola, S. Foster, W. O’Brien","doi":"10.1109/T-SU.1985.31592","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31592","url":null,"abstract":"Absrmcf-There has been a lack of an accurate procedure for the measurement of an attenuation coefficient for biological tissues at 100 MHz with the scanning laser acoustic microscope (SLAM). The solution to this problem has been approached with two general schemes. One involved a calibrated look-up table, and the other utilized the measurement of insertion loss. For the latter a procedure has been developed and verified using known biological solutions. The insertion loss procedure yields an attenuation coefficient uncertainty to within five percent, a dynamic range from 4 to 28 dB/mm. and an insertion loss sensitivity of 0.2 dB. N IMPORTANT tissue characterization property is the ultrasonic attenuation coefficient, which is the decrease in energy of the sound wave when it propagates through a material. The attenuation includes absorption and scattering. Absorption represents the loss of energy into heat within the specimen. Scattering is a redirection of the energy due to the inhomogeneities of the specimen and includes reflection, refraction, and diffraction. The scanning laser acoustic microscope (SLAM) is a useful tool for providing at 100 MHz, the ultrasonic attenuation coefficient of tissue. A number of techniques have been developed to perform this measurement with the SLAM, and this report details and evaluates these techniques. Details of ultrasonic velocity measurements are found in companion papers [l], [2].","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132149999","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}
Absfmct-The design and industrial applications of a Quate-Lemons scanning acoustic microscope are described. The microscope is based on a conventional optical microscope, and so comparisons between the two modes are easily made; the instrument is simple to set up and operates routinely in an industrial environment. The basis of the instrument is a miniature lens scanner, little larger than an optical objective lens, which mounts on the turret of an optical microscope. Selection between modes is simply achieved by turret rotation, ensuring good registration between images. An integrated computer system is used to control the instrument, recording images and V(z) curves into a 512point square digital frame store, and this is also used for image processing. The design of the microwave electronics is explained, and emphasis is put on the low frequency performance of the system. This is illustrated with interior images of production components.
{"title":"An Acoustic Microscope for Industrial Applications","authors":"I. R. Smith, R. Harvey, D. Fathers","doi":"10.1109/T-SU.1985.31594","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31594","url":null,"abstract":"Absfmct-The design and industrial applications of a Quate-Lemons scanning acoustic microscope are described. The microscope is based on a conventional optical microscope, and so comparisons between the two modes are easily made; the instrument is simple to set up and operates routinely in an industrial environment. The basis of the instrument is a miniature lens scanner, little larger than an optical objective lens, which mounts on the turret of an optical microscope. Selection between modes is simply achieved by turret rotation, ensuring good registration between images. An integrated computer system is used to control the instrument, recording images and V(z) curves into a 512point square digital frame store, and this is also used for image processing. The design of the microwave electronics is explained, and emphasis is put on the low frequency performance of the system. This is illustrated with interior images of production components.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129006524","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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