Design And Optimization Of An Electron Injection Trench Gate IGBT

IGBT is a bipolar junction transistor, which is controlled by voltage. It has become the most popular device in the field of power electronics because of its advantages such as simple control, low on-state voltage drop, large on-state current and low loss.With the rapid development of automotive electronics, high-speed rail transportation, power system, variable frequency electrical appliances and other industries, the demand of IGBT is increasing rapidly. However, the domestic IGBT technology is still in its infancy, the ability to design the chips is relatively weak. In this work, related electrical properties of IGBT has been researched, which is based on 1700V NPT-IGBT design and test. And on this basis, continue the discussion and analysis of the new structure. Main works are as follows:(1) It is concentrated on introducing the background and development of IGBT and the advantages and disadvantages of past IGBTs, analyzing the structure, operation principle, static and switching characteristics of IGBT. Also, some common methods to reduce the conduction voltage drop and improve the switching speed of IGBT has been mentioned.(2) Completed the design and test of 1700V planar NPT-IGBT. In the design of the cell, the parameters such as the thickness of the device, the substrate resistivity, the impurity concentration of JFET, the length of the gate, the junction depth and the impurity concentration of the P-well region are determined by the blocking capbility and the conduction voltage drop of this IGBT. In the junction terminal part, we introduces several general junction terminal technology, and the junction terminal structure meeting the requirements of the project has been designed successfully. Drew the layout according to the designed cell and junction terminal parameters and taped out successfully. At the last of this part, the test and analysis of the chip has been done.(3) In this part, the model of electron injection, which can reduce the conduction voltage drop and turn-off loss simutaneously, is explored. And a kind of trench IGBT structure, electron injection IGBT (EI-IGBT), is proposed. Based on this structure, the electron injection model in the process of on-state and off states is analysized, and the static characteristics,switching characteristics, temperature characteristics and safe operating area of EI-IGBT are discussed. The influence of the reverse current injection on the turn-off process is analyzed in detail. At last, the feasibility of EI-IGBT is discussed,and the combined simulation of the process and the device is carried out, and the results are consistent with the single MEDICI simulation.