Accelerated life time estimation of the MEMS devices in the thermal influence

Accelerated life time estimation of devices was investigated under the constant thermal influence. And by using Coffin-Manson model the accelerated factor which occurs due to thermal cycling and frequency cycling was calculated. At first, this equation was simplified to calculate life time. And the limitation of this equation was discussed. Secondly, the deformation and stress of the solder joint could also be significantly influenced by a thermal shock. The deformations and stresses of three types of the solder were calculated by using COMSOL - Multiphysics software. The temperature range was from T
_max
+85 °C to T
_min
-40 °C. For thermal shock loading the ramp rate was 100 °C /min. The higher the ramp rate, the higher stress and larger deformation of the solder joint is.