Trench gate insulated gate bipolar transistor (IGBT) device and manufacturing method thereof

Abstract

The present invention relates to a trench gate IGBT device and a manufacturing method thereof, and belongs to the power semiconductor device technology field, and relates to an insulated gate bipolar transistor. According to the present invention, by introducing a composite trench structure and a carrier storage layer which are coupled mutually, and introducing an electrode connected with an emitter at the bottom of a gate electrode of an injection enhanced gate transistor (IEGT) device, on one hand, the depth and width of the gate electrode are reduced under a certain trench depth and width, on the other hand, by the shielding effect of the introduced electrode connected with the emitter, the gate capacitance, especially the gate-collector capacitance of the device is reduced, the switching speed of the device is improved, the switching loss of the device is reduced. Meanwhile, by introducing the coupled carrier storage layer, the adverse effect to the positive conduction characteristic of the device which is caused by introducing the gate electrode connected with the emitter is compensated, further the carrier concentration distribution of a whole drift region is improved, and the better compromise of the device positive conduction voltage drop and the switching loss is obtained.

Description

Technical field [0001] The invention belongs to the technical field of power semiconductor devices, and relates to an insulated gate bipolar transistor (IGBT), and in particular to an injection-enhanced trench gate insulated gate bipolar transistor (Injection-Enhanced Gate Transistor, IEGT). Background technique [0002] Insulated gate bipolar transistor (IGBT) is a new type of power electronic device that combines MOS field effect and bipolar transistor. It not only has the advantages of MOSFET easy drive and simple control, but also has the advantages of reduced power transistor conduction voltage, large on-state current, and low loss. It has become one of the core electronic components in modern power electronic circuits and is widely used in Various fields of the national economy such as communications, energy, transportation, industry, medicine, household appliances, and aerospace. The application of IGBT has played an extremely important role in improving the performance o...

AI Technical Summary

Problems solved by technology

The present invention introduces an electrode connected to the emitter at the bottom of the gate electrode of the IEGT device through the introduction of the mutually coupled composite trench structure and the carrier storage layer. The depth and width of the electrode, on the other hand, reduces the gate capacitance of the device, especially the gate-collector capacitance, by introducing the shielding effect of the electrode connected to the emitter, increasing the switching speed of the device and reducing the switching speed of the device. At the same time, the introduction of the coupled carrier storage layer compensates for the adverse effect on the forward conduction characteristics of the device due to the introduction of the lower gate electrode connected to the emitter, further improving the carrier concentration distribution in the entire drift region, and obtaining A better compromise between the device forward voltage drop and switching loss; in addition, the thick dielectric layer around the bottom electrode further shields the adverse effect of the N-type charge storage layer on the device breakdown voltage, and in a certain device trench In the case of groove depth and trench MOS structure density, the breakdown voltage of the device is further improved, the concentration of the electric field at the bottom of the trench is improved, and the reliability of the device is further improved

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