A kind of igbt with terminal deep level impurity layer

Abstract

The invention relates to an IGBT with a terminal deep-level impurity layer, which belongs to the technical field of semiconductor power devices. Based on the traditional Planar FS-IGBT, the invention injects a deep energy level impurity layer (15) into the terminal drift region (14). In the deep-level impurity layer (15), as the temperature of the device increases, the ionization degree of the deep-level impurities increases, and the impurity concentration increases significantly. When the IGBT is turned off, the increased carrier concentration in the terminal drift region is effectively reduced. The hole emission efficiency of the P+ collector region in the small terminal region reduces the parasitic PNP transistor αPNP, thereby effectively reducing the high-temperature leakage current of the device; the increased electron concentration in the drift region and the accelerated recombination of holes injected into the P+ collector region, and deep energy The level impurity itself is a recombination center, further accelerating the recombination of electrons and holes, effectively improving the turn-off characteristics and improving the reliability of the IGBT.

Description

Technical field [0001] The invention belongs to the technical field of semiconductor power devices, and relates to an insulated gate bipolar transistor (IGBT). Background technique [0002] IGBT not only has the advantages of MOSFET's high input impedance, low control power, simple drive circuit, and high switching speed, but also has the advantages of high current density of bipolar power transistors, reduced saturation voltage, and strong current handling capabilities. Therefore, the three major characteristics of IGBT power devices are high voltage, high current, and high speed, which are unmatched by other power devices. Therefore, it is a very ideal switching device in the field of power electronics. IGBT products combine the three major technical advantages of high frequency, high voltage and high current. At the same time, IGBT can realize energy saving and emission reduction, and has good environmental protection benefits. IGBT is widely used in the power field , Consume...

AI Technical Summary

Problems solved by technology

The biggest advantage of IGBT is that it can withstand the current impact no matter in the conduction state or in the short circuit state. The disadvantage is that the internal resistance of the high-voltage IGBT is large, resulting in large conduction loss. Multiple in series, and low tolerance for overvoltage, overheating, impact resistance, anti-interference, etc.

[0003] When the IGBT is forward-conducting, the positive gate voltage makes the channel open, and the emitter electrons flow through the channel to the drift region. Due to the forward bias of the collector, a large number of holes in the collector region flood into the drift region, and the drift region A large number of electrons have a conductance modulation effect, which can make the turn-on voltage drop of the IGBT much smaller than that of the VDMOS; when the IGBT is turned off, the gate voltage is negative voltage or zero voltage, the emitter electrons suddenly disappear, and the collector is high Voltage, a large number of holes continue to flow to the drift region, forming a large hole current, at this time the IGBT is in the reverse blocking state, due to the parasitic PNP tube α PNP As the temperature increases sharply, the leakage current of the IGBT increases significantly with the increase of temperature. High temperature and large leakage current can easily cause avalanche breakdown or even burn out of the device.

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