Stress measurements in microelectronic packaging through piezoresistive sensors take the advantage of both insitu and non-destructive. In this study, test chips with both p-type and n-type piezoresistive stress sensors as well as a heat source were first designed, then manufactured by a commercialized foundry so that the uniformity of the test chips were expected. Both temperature and stress calibrations were next performed through a special designed MQFP(Metal QFP) and four-point bending (4PB) structure, respectively. Measurements of stress which is produced due to both manufacturing process and thermal effects on the test chips were finally executed in this paper, and approximately linear relationships were observed between stress and temperature as well as stress and input power. It is concluded that n-type piezoresistive stress sensors are able to extract stress in microelectronic packaging with good accuracy.
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