General linearized model use for High Power Reliability Assessment test results: Conditions, procedure and case study
Abstract In semiconductor manufacturing for automotive, AECQ_100 standard requires test of load drivers in continuous short circuit conditions: this test is called High Power Reliability Assessment (HPRA). It is about a robustness test in which a sample of parts is led to breakages on a cycled overload or short circuit current. The test is stopped when a sufficient number of parts to conduct a statistical analysis failed. The expected result from this statistical analysis is failure cycle modeling according to the test temperature. But this is a complex modeling that has to proceed in several steps, the final step being use of a general linearized model. This paper presents the main features of modeling, but it shows their implementation on a real HPRA test in Load Short Circuit (LSC) condition. Modeling allows result prediction at a temperature for which a test has not been performed, but it allows also a full explanation of the phenomena: for example, it enables to estimate activation energy of acceleration factor in the test, but also the failure mechanisms at the breakage origin. This paper highlights the necessary conditions for the tests so that interpretation may be complete and significant.