Reliability of multilayer ceramic capacitors after thermal shock

It is shown that critical-stress intensity factor K/sub 1C/, thermal diffusivity, Young´s modulus and the chip geometry are important factors in understanding the thermal-shock-behavior of chips. Examples of changes in thermal-shock behavior with changes in K/sub 1C/ and chip thickness are shown. Multilayer ceramic capacitors were tested for degradation of insulation resistance after being boiled in a 1.3 N NaCl solution for an hour as well as during life testing and 85 degrees C/85% RH testing. Results show that chips made with optimized parameters exhibit negligible low-thermal-shock failures and very low failure rates during life and 85 degrees C/85% RH testing. Similar results are shown for laser-marked parts where laser-marked surfaces could be expected to act as crack initiation and propagation sites. Results clearly show that laser marking does not create any flaws that are detrimental to the reliability of these devices.<>