Detection Resolution of Acoustic Microscopy in Micro-Scale

Abstract

Scanning acoustic microscopy (SAM) is a powerful non-destructive testing tool used in the field of electronic package, micro-and nanomaterial and medication. The capability to distinct how minimum of defect is very important to detect the flaw in electronic packages. The detection resolution of SAM depends on the frequency of ultrasonic focus transducers. In this paper, the Multi-Gaussian Beam model to simulate the sound field of the focused transducers is discussed. Mainly the frequency domain imaging algorithm and 2D-Deconvolution method for better image quality and high resolution is analyzed. Finally, the calibration experiments for the detection resolution of 100MHZ transducer is carried out. In addition, the micro flaws with different dimensions are observed at different defocusing location. It is concluded that the detection resolution decreases with the deviating from focus plane, so the flaws should be sensitive on the focus area by precisely controlling the vertical position for better detection resolution.

Detection Resolution Analysis of Scanning Acoustic Microscopy Used in Electronic Packaging

“…However, with the increasing of frequency, the attenuation of ultrasound energy becomes more serious which means that the amplitude of reflected ultrasonic signal decreases. In other words, higher resolution results in lower penetration depth [4]. So, different test objects require different frequency ultrasonic transducer.…”