IGBT apparatus provided with internal JFET structure

Abstract

The invention relates to an IGBT apparatus provided with an internal JFET structure and belongs to the technical field of power semiconductor apparatuses. According to the IGBT apparatus structure, byintroducing a JEFT region in a body region of a conventional grate IGBT, the JFET region is equivalent to a variable resistor, a hole is stored when the apparatus is conducted forward and a quick releasing circuit is provided for the hole in forward blockage, so that the saturated conducting pressure drop and cut-off loss of the apparatus are reduced, the short-circuit failure phenomenon after the apparatus is cut off is avoided, and the cut-off ability of the apparatus is improved; moreover, a connecting bridge connecting the grate structure and the JFET region plays a field plate role whenthe apparatus is blocked forwardly, so that the electric field peak on the surface of the lower region of the connecting bridge is reduced effectively, and the voltage-resistant and operational reliability of the apparatus is improved. The IGBT apparatus provided with the internal JFET structure is compatible to an existing high voltage IGBT apparatus manufacturing process, so that industrialization is achieved favorably.

Description

technical field [0001] The invention belongs to the technical field of power semiconductor devices, and in particular relates to an IGBT device with a built-in JFET structure. Background technique [0002] With the rapid development of rail transit, smart grid, green energy and other fields, insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT) has simple gate control, high input impedance, fast switching speed, high current density, saturation voltage It has become one of the mainstream power switching devices in the field of medium and high power power electronics; at the same time, it will continue to develop in the direction of high voltage, high current, high operating temperature and high reliability. The application of IGBT devices in high-voltage applications, especially in the process of motor driving, will experience a short circuit at both ends of the device; the device will be turned on when the load is short-circuited, resulting in a short-...

AI Technical Summary

Problems solved by technology

However, the FP region between the trench gates stores excess holes during forward conduction, which will introduce negative gate capacitance effect to generate displacement current in the gate, which affects the gate control ability; it takes time for the hole current to discharge when it is turned off, making the device The turn-off loss increases

At the same time, if the holes cannot be extracted from the FP region in time during the turn-off process, the leakage current after turn-off will be too large, which will induce delayed failure and reduce the turn-off capability of the device.

The existing solution provides a discharge path for holes in the FP region when it is turned off by introducing clamping diodes and diffusion resistors, but it exposes problems such as low discharge efficiency and damaged device breakdown voltage.

Images