Acoustic Microscopy Imaging Research Articles

特集 はんだ接合部の評価，検査技術 レーザー走査型超音波顕微鏡によるマルチチップモジュールの視覚化とその接合評価

特集 はんだ接合部の評価，検査技術 レーザー走査型超音波顕微鏡によるマルチチップモジュールの視覚化とその接合評価

A study of the mechanical property of materials using acoustic microscopy

The interpretation of the general features of acoustic microscopy images is discussed in conjunction with its application to materials science under the following topics. (1) Interference fringes have been discovered around surface breaking cracks, and a model based on the leaky Rayleigh wave has been proposed. It has attracted a considerable amount of interest because these fringes might give new information on the elastic properties of microscopic discontinuity such as cracks, grain boundaries, and steps that are almost normal in sample surfaces. (2) When subsurface cracks are close to parallel to the sample surface, they can be analyzed by a simple plate model with water or air below. Either the V(z) curve measurement or the resonance method is useful depending on whether the frequency-depth product is much smaller or close to the first cutoff of the higher-order modes of the leaky Lamb waves. This analysis was successfully applied to a study of indentation fractures of steel ball bearings in use. (3) Image observation and the leaky SSCW velocity measurement at 775 MHz have been applied to individual spherulites in semicrystalline polypropylene. Through the signal processing of the V(x,z) image, it has been found that the difference in velocity between spherulites with different thermal histories can be larger than 30%.

Review of scanning laser acoustic microscopy—Imaging applications

The scanning laser acoustic microscope (SLAM) was first developed in the early 1970s as a laboratory curiosity to make high-resolution images of materials in the expectation that microstructure could be studied in a new way. Since that time the techniques have developed into practical and commercially available instruments that have found their way into industry by solving very important problems in quality control. Stimulated by the evolution of new materials and processes, for example, fine ceramics, composites, and the ever-changing field of microelectronics, SLAM has often played an important role as an analytical tool, alongside other analytical instruments to “see inside” products nondestructively, in true real-time and with higher resolution than had been possible with conventional ultrasonic imaging.

Excimer Laser Thin Metallic Film Patterning on Polyvinyledene Difluoridea)

ABSTRACTTactile sensors and ultrasonic transducers based on the piezoelectric properties of polyvinyledene difluoride, PVF2, usually take the form of thin 10 - 110 μm polymer films coated on one or both sides with a metallic film. Electrode patterns are usually fabricated by photolithography that requires a 90 °C baking process which may harm the piezoelectric properties of the PVF2 film. We have developed an alternate method, based on direct patterning with a XeCl laser, yielding complex patterns of lines as narrow as 20 μm which are better than those fabricated by photolithography. The metallic film is ablated on both sides of the polymer while maintaining the intrinsic properties of the PVF2. The ablation mechanism is investigated using transmission optical, scanning electron, and scanning acoustic microscope images. The performance of an ultrasonic transducer fabricated with this technique is described.

Measurement of cellular elastic properties by acoustic microscopy

The acoustic microscope is used to investigate the elastic properties of living biological cells. A quantitative model is developed relating acoustic microscope image contrast to cellular elastic properties. Cytoplasmic acoustic attenuation is measured by focusing the acoustic microscope on the surface of the underlying substrate. Cytoplasmic acoustic impedance is measured by focusing the acoustic microscope on the top surface of the cell. The model allows the acoustic microscope to give quantitative information about cellular elasticity on a subcellular scale.

Acoustic microscope images of rock samples : Danburg, J S; Yuhas, D E Geophys Res Lett, V5, N10, Oct 1978, P885–888

Acoustic microscope images of rock samples : Danburg, J S; Yuhas, D E Geophys Res Lett, V5, N10, Oct 1978, P885–888

Review of acousto-optic interactions

This paper reviews the theory of acousto-optic interactions. From a qualitative approach the acousto-optic interactions can be explained from the scattering of the phonons. By examining the conservation of momentum and energy in the particle interactions, the basic relations of the acousto-optic interaction can be obtained. From the rigorous wave theory approach, the details of the acousto-optic interactions are obtained. Acousto-optic interactions are generally divided into two dominant regions, the Raman-Nath and the Bragg regions and their differences will be discussed. Acousto-optic interactions with a sound beam generated by a transducer array will also be discussed. The basic theory of acousto-optic interactions presented in this paper is the basis for applications in acoustic microscopy and acoustic imaging.

Acoustic microscope images of rock samples

We have used an acoustic microscope to examine polished sections of sedimentary rock samples, producing elastic‐wave images with a resolution of about 25 μ. We have observed variations of rock elastic properties on a granular scale and compared them with optical features in the same field of view.