Temperature cycling and thermal shock correlation in DPAK & DSO packages

Short time to market is important in ensuring the competitiveness of a new semiconductor product. With the need to pass the listed qualification reliability stress test, temperature cycling (TC) is one of the stress tests that required the most time. Therefore, in order to speed up the stress test duration of TC, an initiative to assess the possibility of replacing TC with thermal shock (TS) in development stage was proposed. TS apply the similar failure mechanism model of Coffin Manson as TC. The main differences of both tests used in this study were the medium of the test environment (air-to-air in TC & liquid-to-liquid in TS), dwell time, time to reach specified temperature and load transfer time. With the conscious of the differences, a correlation study of TC to TS was carried out using DPAK and DSO packages as test vehicles. Positive results were reported in this correlation for the defined failure mode of the de-lamination percentage (%) at the interfaces of die pad to EMC, die-attach to lead frame/die pad. As a conclusion, TC H condition is correlated to 2x TS and TC C condition for die pad de-lamination in DPAK and DSO packages. These have been implemented in development stage of a project.