Mission profile driven component design for adjusting product lifetime on system level
The design of power electronics modules has always been carried out with major focus on product reliability. As the chip sizes and module sizes shrink, but the power dissipation remains constant or even increases, the growing power densities create thermal problems which make designers explore new die attach, substrate and bonding technologies, bringing thermal design to its limits. On the other hand the requirements of the application, the final product which will make use of the power modules may give some additional margin to the designer. If the expected lifetime and the so-called `mission profile’, in other words operating requirements of the target application is known, the reliability requirements for the power modules can be more accurately defined.
The mission profile will directly result in a power profile, which will determine the top junction temperature and the junction temperature swings in the module. Having this information and the possibility to create accurate lifetime tests the requirements of the final application and the module design can be synchronized, giving more freedom, yet more responsibility to the designer to fine tune the power module’s reliability characteristics. In this article we would like to show the detailed steps of the above described process.