Scanning Acoustic Microscopy SAM

This technique is also known as scanning acoustic tomography. This is a powerful tool for spotting delaminations, cracks, and other anomalies non-destructively. Not only does acoustic microscopy detect the failures but it can also provide the specific location of the problem. SAM high-resolution images and advanced diagnostic tools are used to  

The extent of process and quality control used in weldbonding (Chapter 8) must be based on the end use of the hardware being bonded. Methods in current use should be selected to fit a specific application. Consistent joint strength can be assured by evaluating cured weldbond tensile-shear specimens, cleaned with each batch of parts, for strength and bond quality. Consistent weld quality can be assured by hourly evaluation of uncured tensile shear and macro specimens for strength and weld quality. Even higher assurance can be obtained from the use of an in-process weld monitor that 

De Lollis, N.J., Adhesives, Adherends, Adhesion, Robert E. Kileger Publishing Company, Huntington, NY, 1985. 

A quality-control system for adhesive bonding utilizing ultrasonic testing. Applied Polymer Symposia No. 3 (M J. Bodnar, ed.), pp. 411-434, 1966. 

Society of Manufacturing Engineers, Adhesives in Modem Manufacturing (E.J. Bruno, ed.), 1970. 

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Scanning acoustic microscopy (SAM) is a relatively new technique which broke through in the mid-seventies and was commercialized recently. The SAM uses sound to create visual images of variations in the mechanical properties of samples. The ability of acoustic waves to penetrate optically opaque materials makes it possible to provide surface or subsurface stmctural images nondestmctively, which might... 

Revay, L., Lindblad, G., and Lind, L. (1990). IC package defects revealed by scanning acoustic microscopy (SAM). CERT 90 Components engineering, Reliability and Test Conference (Electron. Components Inst.), pp. 115-22. [199]... 

Fourier transform infrared spectroscopy (FTIR) ASTM E1421 Elongation tests Scanning electronic microscopy (SEM) Differential scanning calorimetry (DSC) ASTM D3417 Scanning acoustic microscopy (SAM)... 

A nondestructive thermoacoustic material signature (TAMS) imaging method in scanning acoustic microscopy (SAM) was recently utilized to study the matrix and tempers signatures of ancient ceramics (90). 

After RGA data are collected and analyzed, the package is delidded to examine the inside components, interconnections, materials, and surfaces. Because removing the lid is a destructive process, it should be done in a lid-down position with special equipment to vacuum off any debris. After delidding, the components, surfaces, and connections are optically examined followed by analytical testing such surface analysis for contaminants, especially chloride and sodium ions. Scanning acoustical microscopy (SAM) is very useful in detecting voids, cracks or delamination within the adhesive or at the adhesive bond line. An excellent overview of SAM and its variations may be found in Ardebili and Pecht. ... 

Scanning acoustic microscopy (SAM) is an ideal nondestructive method for revealing internal flaws within materials or between material interfaces. SAM is extensively used in detecting voids, delamination, and other separations that can occur in adhesive-attached parts, especially after thermal cycling. SAM is particularly useful in the analysis or evaluation of many types of electronic parts, including ceramic and plastic-encapsulated ICs, plastic-encapsulated microcircuits (PEMs), hybrid micro-circuits, CSPs, PBGAs, and printed-wiring boards. 

Chemical homogeneity can be evaluated using OM, SEM in the backscatter mode or with EDS dot maps, and scanning acoustic microscopy (SAM). Phase distribution and chemical homogeneity can also be assessed with micrographs and quantitative... 

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