The change process of the amplifier gain of bipolar transistors encapsulated in small outline J-leaded packages (SOJ-type packages) during temperature cycling test is discussed. The amplifier gain changes almost linearly with the applied uni-axial stress. The residual stress of the LSI chip is found to change during the temperature cycling test by applying stress-sensing test chips. It is found by applying a finite element analysis and ultrasonic inspection that the stress change is due to delamination at interface between the LSI chip and the encapsulant resin. The predicted amplifier gain change due to this delamination agrees well with the measured result.
|Number of pages||6|
|Publication status||Published - 1995|
|Event||Proceedings of the 1995 ASME International Mechanical Engineering Congress and Exposition - San Francisco, CA, USA|
Duration: 1995 Nov 12 → 1995 Nov 17
|Conference||Proceedings of the 1995 ASME International Mechanical Engineering Congress and Exposition|
|City||San Francisco, CA, USA|
|Period||95/11/12 → 95/11/17|