Speed of sound evaluation considering spatial resolution in a scanning acoustic microscopy system capable of observing wide spatial area

Abstract The electronics supply chain is being increasingly infiltrated by non-authentic, counterfeit electronic parts, whose use poses a great risk to the integrity and quality of critical hardware. There is a wide range of counterfeit parts such as leads and body molds. The failure analyst has many tools that can be used to investigate counterfeit parts. The key is to follow an investigative path that makes sense for each scenario. External visual inspection is called for whenever the source of supply is questionable. Other methods include use of solvents, 3D measurement, X-ray fluorescence, C-mode scanning acoustic microscopy, thermal cycle testing, burn-in technique, and electrical testing. Awareness, vigilance, and effective investigations are the best defense against the threat of counterfeit parts.

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Failure Analysis of Broken Stitch Bonds in TSSOP Packages Using Scanning Acoustic Microscopy (SAM) and Time Domain Reflectometry (TDR)

ISTFA 2004: Conference Proceedings from the 30th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2004p0623 ◽

2004 ◽

Author(s):

Bilal Abd-AlRahman ◽

Corey Lewis ◽

Todd Simons

Keyword(s):

Failure Analysis ◽

Mechanical Stress ◽

Time Domain ◽

Open Circuit ◽

Time Domain Reflectometry ◽

Acoustic Microscopy ◽

Scanning Acoustic Microscopy ◽

Root Cause ◽

Analysis Application

Abstract A failure analysis application utilizing scanning acoustic microscopy (SAM) and time domain reflectometry (TDR) for failure analysis has been developed to isolate broken stitch bonds in thin shrink small outline package (TSSOP) devices. Open circuit failures have occurred in this package due to excessive bending of the leads during assembly. The tools and their specific application to this technique as well as the limitations of C-SAM, TDR and radiographic analyses are discussed. By coupling C-SAM and TDR, a failure analyst can confidently determine whether the cause of an open circuit in a TSSOP package is located at the stitch bond. The root cause of the failure was determined to be abnormal mechanical stress placed on the pins during the lead forming operation. While C-SAM and TDR had proven useful in the analysis of TSSOP packages, it can potentially be expanded to other wire-bonded packages.

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Stacked Die Analysis Using C-mode Scanning Acoustic Microscope

ISTFA 2005: Conference Proceedings from the 31st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2005p0189 ◽

2005 ◽

Author(s):

Li Na ◽

Jawed Khan ◽

Lonnie Adams

Keyword(s):

Data Acquisition ◽

Image Interpretation ◽

Acoustic Microscopy ◽

Scanning Acoustic Microscopy ◽

Acoustic Microscope ◽

Analysis Mode ◽

Scanning Acoustic Microscope

Abstract For stacked die package delamination inspection using C-mode acoustic microscope, traditional interface and thorough scan techniques cannot give enough of information when the delamination occurs in multi-interfaces, and echoes from adjacent interfaces are not sufficiently separated from each other. A thinner thickness in the stacked-die package could complicate C-mode scanning acoustic microscopy (CSAM) analysis and sometimes may lead to false interpretations. The first objective of this paper is to briefly explain the CSAM mechanism. Based on that, some of the drawbacks of current settings in detecting the delamination for stacked-die packages are presented. The last objective is to introduce quantitative B-scan analysis mode (Q-BAM) and Zip-Slice technologies in order to better understand and improve the reliability of detecting the delamination in stacked-die packages. Therefore, a large portion of this paper focuses on the Q-BAM and Zip-Slice data acquisition and image interpretation.

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