High-Resolution Ultrasonic Inspection Images of Semiconductor Packages by Advanced High-Frequency Transducers

This paper describes a method for obtaining high-resolution ultrasonic inspection images of semiconductor packages. We evaluated the effect of the incident ultrasonic frequency on the resolution and defect detection. When the incident frequency of the ultrasonic transducers is changed from 300 MHz to 400 MHz, the capability to detect package defect improves from 2.5 µm to 1.0 µm. The observed images of semiconductor packages proves that a 400 MHz transducer can be applied to inspect sophisticated LSIs.