Packaging Structure Design And Process Implementation Of Novel Power Rectifier Module

As the core component of industrial high-power power supply,the main function of power rectifier module is to realize AC-DC conversion and provide stable and high-quality voltage for industrial equipment.Existing power rectifier modules(or rectifier stacks)have complex packaging structures and unsatisfactory electrical and thermal properties,and it is urgent to try to design a new power rectifier module packaging structure by combining new process methods.This topic designs a new packaging structure for the typical failure forms and pain points of traditional power rectifier modules,analyses the electro-thermal performance of the new packaging structure through finite element simulation technology,and designs its process flow to realize the manufacturing,testing and verification analysis of the new power rectifier module.The research content and main findings of the project are as follows:(1)Study the typical failure forms of traditional power rectifier modules;establish a multi-physical field coupling model of electric-thermal-force of traditional power rectifier modules;analyse typical failure locations,failure forms and failure causes;then analyse the pain points of traditional packaging structures in terms of process flow and manufacturing costs.The results show that the traditional packaging structure has poor heat dissipation capability,the chip is subject to complex forces,the edge of the solder layer is prone to cracking and delamination under thermal stress,and the chip is prone to tearing under the combined effects of thermal stress,terminal torque and axial force of the positioning screw.Finally,it is concluded that the traditional packaging structure has complex process flow,low automation and high manufacturing cost.(2)Design and performance simulation analysis of the new packaging structure.In view of the typical failure forms and pain points of the traditional power rectifier module,a new packaging structure is designed;the electric-thermal-force multi-physical field coupling model and Q3 D electromagnetic field model of the new power rectifier module are established;the results show that the new power rectifier module provides better thermal performance.The finite element simulation shows that the chip temperature and stress of the new power rectifier module are 4.83% and 24.19% lower than those of the conventional power rectifier module chip during conduction;in terms of electrical performance,the parasitic inductance of the new power rectifier module is slightly higher than that of the conventional power rectifier module by 0.67 n H,but it has excellent electrical performance.(3)Simulation study of the influence of the packaging process on the performance of the power rectifier module.Based on the core bonding process of the new power rectifier module: welding process and lead bonding process,the effect of welding position and bonding wire diameter,number of roots and other factors on the performance of the new power rectifier module is explored through finite element simulation.The study shows that under the fixed DBC position,shortening the distance of the chip from the DBC substrate can effectively reduce the temperature and stress of the chip,and effectively reduce the parasitic inductance of the module;in the lead bonding process,the use of large wire diameter and multiple bonding wires in parallel can also effectively reduce the temperature and stress of the chip,and can reduce the parasitic inductance of the overall package.(4)Design the actual manufacturing process flow of the new power rectifier module.Select the package material,realise the fabrication,prototype,and test and analyse the electrical properties of the sample.The results show that the actual prototype,can be effectively manufactured through the designed process.The achieved new power rectifier module has a breakdown voltage of up to 115 V and a forward voltage of 0.61-0.62 V under operating conditions,with excellent electrical and thermal properties such as high voltage withstand and low power consumption.This paper designs and develops a new power rectifier module,and the research results are of good guidance for the design,process realisation and engineering application of power rectifier module products.