A MOS gate-controlled thyristor with integrated Schottky diode and its preparation method

Abstract

The invention belongs to the technical field of power semiconductor devices and relates to an MOS (Metal Oxide Semiconductor) gated thyristor integrating a Schottky diode. According to the MOS gated thyristor provided by the invention, a device cathode is designed to be in contact with Schottky, so that one Schottky diode is formed between a P trap region and the cathode, wherein the pumping of acharge carrier in a switching-off process can be accelerated by a P+ region, but the pulse performance of the device is not influenced; in a manufacturing process, whether the P+ region is remained ornot can be selected according to requirements. By adopting two structures, the current distribution is more uniform when the device works and the minimum current needed by a latch of the device is reduced; pulse peak value current is further improved under small current and the increasing rate of the current (di / dt) is improved; the time of the device which works under an IGBT (Insulated Gate Bipolar Transistor) mode is shortened; the crystal lattice temperature of the device which works under the IGBT mode at an pulse discharging initial stage of the device is effectively reduced, and furthermore, pulse properties of the device are improved.

Description

technical field [0001] The invention belongs to the technical field of power semiconductor devices, and relates to a MOS gate-controlled thyristor (SD-MCT) integrating Schottky diodes and a preparation method thereof. Background technique [0002] Pulse power technology is a new science and technology developed in the early 1960s due to the needs of national defense research. Simply put, pulse power technology is an electrophysical technology that quickly compresses the energy stored slowly and releases it to the load in the form of pulses. With the development of nuclear physics, electron beam accelerator physics, laser and plasma physics research, pulse power technology has developed rapidly and has become one of the most active cutting-edge technologies in the world. It has broad application prospects in both military and civilian fields. In the military field, it is used in nuclear fusion technology, fuze systems for national defense and military defense, etc.; in the c...

AI Technical Summary

Problems solved by technology

However, due to the current concentration effect during the turn-on process, the di / dt capability of the thyristor is poor

In addition, thyristors are flow-controlled devices, and their driving circuits are more complicated than voltage-controlled devices

IGBT is mainly used in high-frequency medium pulse power supply. IGBT is a voltage-controlled device, and the drive is relatively simple. However, the degree of conductance modulation of IGBT is limited by the drift region and the reverse-biased PN junction of the P-type base region, resulting in the conduction power consumption of the device. Larger; in addition, the conduction of the IGBT is controlled by the gate voltage, and the maximum current is also limited by the saturation current

Gate Controlled Thyristor ( M OS- C onrolled T hyristor, MCT) has low-resistance characteristics similar to thyristors, and has high di / dt capability and voltage control characteristics, but the device needs gate control signals of different signs during the switching process, resulting in more complex drive circuits (Temple V A K.MOS controlled thyristors (MCT's)[C].Electron Devices Meeting,1984International.IEEE,1984:282-285.)

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