Scanning Acoustic Microscopy (SAM): A Robust Method for Defect Detection during the Manufacturing Process of...

Area of Science:

• Materials Science
• Biomedical Engineering
• Non-Destructive Testing

Background:

• Reliable non-destructive testing (NDT) is crucial for quality control in the competitive electronics and biomedical markets.
• Miniaturized electronic components, like ultrasonic transducer acoustic stacks, require robust NDT methods for failure analysis.
• Current NDT techniques face limitations with complex, multi-layered microstructures.

Purpose of the Study:

• To evaluate the feasibility of Scanning Acoustic Microscopy (SAM) for non-destructive damage detection in ultrasound (US) probes during manufacturing.
• To assess the internal integrity and quality compliance of US probe acoustic stacks.
• To identify advantages of SAM for manufacturers focused on process improvement and in-process inspection.

Main Methods:

• Industrial application of SAM was studied on 24 phased array probe samples.
• Internal integrity, damages, and quality requirements compliance were investigated.
• Defects detected by SAM were compared with electroacoustic characterization and pulse-echo tests.

Main Results:

• SAM effectively detected delamination, non-homogeneous micron-thick layers, and entrapped air bubbles (blisters) in US probe acoustic stacks.
• The method provided quantitative analysis and defect visualization through 2D images.
• SAM proved to be time-efficient for analyzing multi-layered structures with micron-level thickness.

Conclusions:

• SAM is a valuable non-destructive testing method for quality control in ultrasound probe manufacturing.
• The technique offers advantages in speed and quantitative analysis for micro-scale defects in complex structures.
• SAM supports manufacturers in enhancing process capability, product quality, and in-process inspection for ultrasound probes.