Mixed Multi-physics Simulation Method And Its Application In Reliability Studies Of Package

The development of semiconductor technology has made a greatimprovement in electronic devices, leading to the chip features more rich,the amount of chip pins and chip signal transmission increased rapidly. Atpresent, electronic technology has turned into a new stage from singledevice development to multiple integration, along with this direction,System in package technology has developed gradually and become a hottopic. SIP packaging technology can make the various active or passivedevices or mutual chips which have different function and type into asingle device, leading to a system or a sub system. SIP technology has anadvantage of good process compatibility, low cost and short developmentcycle, currently it is a hot research.However, there are enormous challenges SIP is facing to, some of thekey fundamental problems need to be solved and improved, such asreliability. SIP usually works at high frequencies, it consists lots of variouschip and devices. The high integration density and power density makesthe system’s temperature increase gradually especially underthree-dimensional integration technology. Since the material properties aredepending on temperature, it will cause thermal-mechanical problems.When the yield strength is less than thermal stress, the electronic devicewill fail in fracture mode structure leading to damages in the package.Therefore, the thermal-mechanical analysis makes great contributions forchecking the quality of package structure, it makes a very importantsignificance for studying the reliability of system-level packaging.In this paper, a new wafer level package structure of the system-level reliability has been studied. At the same, we’ve made theelectro-thermal-mechanical analysis of interconnects and wire bonding inLDMOS, explained the experimental phenomena and related quantitativelycalculate the displacement arising due to thermal expansion. This paperuses the mixed-physics simulation methods to solve the coupled problemof electricity, heat and stress. In this paper, we write the program ofmixed-physics method by using hybrid time-domain FEM method andMPI/OPENMP method. The program has improved above50%in solutionefficiency compared to the original program. This paper has implementedthe electro-thermal-stress analysis of interconnect and wire bonding. Thispaper also made a compare between simulation and experiment results. Atthe same time, this paper studied the reliability of a new system-levelpackage, which has a great value for studying the reliability of package.