Design Of 3300V IGBT With Large Current Turn-off Capability

Insulated gate bipolar transistor(IGBT)is a kind of MOS-BJT composite transistor developed on the basis of power MOSFET.It has the common advantages of power BJT and MOSFET,representing the main development direction of current power devices.IGBT is not only used in low-voltage consumer electronics,such as household consumer electronics,but also in high-voltage industrial fields,such as power grid transmission.The design and manufacture of high-voltage IGBT chips are very difficult,and the process requirements are more detailed than the general power devices.High-voltage IGBT is easy to be encountered with large current and other special situations in practical application,and it is necessary to study the turn-off situation to improve the design reliability.We must overcome the design problem and realize the localization of highvoltage IGBT.This thesis is based on a cooperation project with a domestic research institute,mainly carried out the following works:1?3300V IGBT design.Present the main technological process of IGBT based on the basic theory of IGBT and the current technology manufacturing level in China,and introduce the important process steps and details.The design of IGBT mainly includes the design of cell structure and termination structure.Firstly,the cell parameters were determined,including the thickness and resistivity of substrate,the Pbody parameter,the FS layer and collecting area implantation doses.Analyze the influence of different process parameters on the electrical characteristics of the device.This paper introduces the principle of the junction termination,and determines the junction terminal type adopted in this design is the field limit ring and field plate technology.The influence of different process parameters and temperature on the junction termination design is studied,and the stable breakdown voltage and stable electric field distribution are obtained.2?Study on the turn-off characteristics of large current.The process deviation in the actual manufacturing process of IGBT may affect the turn-off capability.The effects of Pbody implantation dose,back P+ implantation dose,cell width,thermal resistance and other parameters on IGBT large current turn-off capability were studied.The change of temperature in the process of turn-off is analyzed by using the electro-thermal coupled device-circuit mixed simulation.Then I analyze the turn-off characteristics of the parallel cell model.According to the simulation,the technological parameters of 3300 V IGBT with large current turn-off capability are proposed,and the device layout is drawn.