Study On Thermal Characteristics And Long-term Life Of Power MOSFETS

As an important part of power electronic circuits,power semiconductor devices have been rapidly used in various fields since their birth with their excellent characteristics.The thermal characteristics of power devices are increasingly valued by industry experts.With the development of integrated circuits,the integration of power devices is getting higher and higher.The power consumption of the circuit is obviously increased.If the heat dissipation problem cannot be solved properly,it will undoubtedly increase the operating junction temperature of the device,which will have an adverse effect on its stability,reliability,and service life.Therefore,it is necessary to analyze the temperature characteristics of the power MOSFET and determine its safe operating area for the design and application of the power MOSFET.In addition,the long storage life of power devices is studied in this paper.As an important state in the life cycle of power devices,long-term storage is of great importance to power devices.Especially for power devices that will be used in systems that require long-term storage and have high reliability requirements,whether the performance of the power devices after long-term storage meets the system requirements can ensure that the system can be successfully powered at one power-up.A very worthy study.Therefore,this article selects three kinds of power devices as research objects,designs and builds a comprehensive stress acceleration test platform,conducts a study on the long-term storage reliability of power devices based on the comprehensive stress of the marine environment,and evaluates the storage reliability evaluation of marine environment power devices.The development has a certain reference value.The main research work and achievements are as follows:1)The thermal instability of power devices was investigated.The trend of the IRF530 N parameters(threshold voltage,on-resistance,transconductance,breakdown voltage,etc.)of the power MOSFET device with temperature was tested.Theoretical analysis.The temperature characteristics of the IRF530 N at different operating points were tested and the characteristics of thermal instability of the IRF530 N were discovered and summarized.According to this,the safe working area of the power device was given,and verified with the actual one,the two are in good agreement.2)Based on the thermal characteristics of power MOSFET devices,a method of testing the thermal resistance using the drain-source current as a sensitive parameter was proposed.The thermal resistance test was performed using the IRF530 N as an example.The error between the test result and phase11 test result is less than 10%.3)Combine the actual conditions of the marine environment,determine the failure sensitive parameters and test conditions,design and build a comprehensive stress test system,using three types of power MOSFET devices(IRF530N,2N7000,and IRLP7843)as test samples,divided into three groups for different Under the conditions of the comprehensive stress accelerated test,the amount of deterioration ofeach set of device parameters over time is recorded.Analysis and summarization of the parameters of the law of degradation.4)Based on traditional Arrhenius and Peck accelerated stress models,combined with accelerated life test data.The storage life of the power MOSFET device was predicted.The results showed that the storage life of the IRF530 N in the marine environment was 8.75×105h,which was approximately 100 years.