| Summary: | 碩士 === 國立虎尾科技大學 === 材料科學與綠色能源工程研究所 === 101 === In this study, straight beam immersion type of ultrasonic detector was used to detect the structural defect(s) inside IC package, where the reflected wave and overlapping effects were discussed through the echo signal ratio in front of and back of the thickness gauge, further incorporated by ANOVA analysis to have further analysis of the reflected wave signals inside IC package and explore the existence of structural defects. In the experiment, the reflected wave peak ratio was measured from the high carbon steel thickness gauge; in the measurement through the brass thickness gauge, due to the grain with thickness of 0.95mm was smaller than that with thickness of 0.75mm, resulting in scattering and further increment of the signal peak ratio; in the experiment, the variation analysis used the critical value of 0.4 to determine the echo signal or noise signal.
In this study, the ultrasonic test results went through authentication process with those in the X-RAY detections, wherein the inner portion of IC package, due to the peeling status generated between the conductive adhesive and the IC chip, formed defects thereon; the results through the Ultrasonic C-SCAN mode were used to authenticate the size of internal defect inside the IC VIA-VT82C486A and location where it was distributed through overlapping signal analysis method; in addition, the package for other North and South bridge IC packages and CPU package were found none of defects through ultrasound and comparison with the X-RAY test results.
Thereafter, the defects generated in the partial VIA-VT82C486A package IC were cut off and placed in metallographic observation to authenticate the results through ultrasound and X-RAY test.
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