Imaging Techniques for Acoustic Microscopy of Microelectronic Circuits
Following the work of Lemons and Quate1, an 800 MHz acoustic microscope has been constructed, operating in the reflection mode for examination of microelectronic materials and devices. To aid in the interpretation of the acoustic images, a method has been developed which produces false color acoustic micrographs of high quality. This technique, along with derivative and logarithmic processing is applied to the acoustic examination of plated structures on organic/ceramic substrates. A standard optical microscope is operated in tandem with the acoustic microscope to allow convenient and absolute comparison between the optical and acoustic images.
KeywordsMicrowave Expense Gallium Polyimide Acoustics
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