Research On Interface Damage Of Power Module Packaged Devices

In today's world,the upgrading of electronic products has promoted the development of electronic information technology,greatly improved people's level of living development,and changed the way people live and work.The power module packaged device is an internal core device of the electronic product,and its reliability is the key to ensure the overall reliability of the electronic product.Overload failure and aging failure are two types of failure mechanisms of devices in microelectronics packages,including brittle fracture,plastic deformation,interface delamination in overload failure,fatigue damage in aging failure,creep,stress cavity,etc.The power module's interface damage will appear at the same time in overload failure and aging failure.It is of great significance to study the interface damage of the power module to reveal the failure of the packaged device.For the interface damage of the power module packaged device,in the past research,mainly focused on device solder joints,solder layers and bonding leads using thermal cycling,power cycle,temperature and humidity cycles and other accelerated failure methods.With the development of electronic devices,the failure and connection of packaged devices have different characteristics.Among them,a series of dynamical excitations such as vibration and shock cause the power module to produce damage at the interface.Adhesion,as a new bond form,is a new research point for interface damage of the power module.In this paper,through the theoretical research,simulation and experimental verification,the two components of the dynamic response damage evolution and the failure prediction of the bonded interface of the power module packaged device are studied.The results of this paper are summarized as follows:(1)Discusses the research status of power modules,and confirms the use of fracture mechanics as a predictive model from a variety of life prediction failure models in the past decades.The cohesion force model is used as the basic predictive model,combined with the existing irreversible degradation cohesion force model obtained through the damage evolution theory,through the cyclic tensile test of DCB specimens,supplemented by the determination of the physical properties of the material,the inversion of cohesion force parameters,and calculations,etc.The damage and degradation of the interface of the material in the cyclic loading and unloading of the specimen were studied to prove the feasibility of the interface damage calculation.(2)Secondary development of Abaqus user unit subroutine interface VUEL.Set up a cohesion unit calculation program applied to the Abaqus explicit calculation module,read and output the calculation parameters of the integration points in all cohesion units through a prefabricated external file,and visualize the interface damage of the data of the integration points of the cohesive unit quantitatively.Characterization.(3)The "alternative method" is proposed as a new calculation method to study the interface damage evolution of power module under dynamic response with lower computational cost and relatively higher computational credibility.Abaqus software and its interface subroutines were used to characterize the entire process of copper-weld interface damage.The calculation method was then verified by the cyclic shear test of solder joints.The comparison of the experimental results verified the power consumption of the power module.The feasibility of the forecast.(4)For the "glued" form of the packaged device,DCB specimens with or without holes in the adhesive layer were prefabricated for tensile failure.Different cohesion models were used to predict the initiation and propagation of cracks.The load-displacement curve was used as a data function.The comparison between the experimental results and the simulation analysis was used as a criterion to compare the traditional Bilinear Cohesion Model with the interpolating model.The final preference determines the more applicable cohesion model.