A gate-controlled thyristor device with improved turn-off characteristics

Abstract

The invention provides a gate-controlled thyristor device with improved turn-off characteristics, in which a metalized anode, a first conductivity type semiconductor substrate, a second conductivity type semiconductor epitaxial layer, and a metallization cathode are sequentially stacked from bottom to top; Type semiconductor well region, second conductivity type semiconductor well region, heavily doped first conductivity type semiconductor region, gate structure; only one side of the second conductivity type semiconductor well region has lightly doped first conductivity type semiconductor region, the lower surface of the lightly doped semiconductor region of the first conductivity type is in contact with the well region of the first conductivity type semiconductor, and the doping concentration and width of the lightly doped semiconductor region of the first conductivity type satisfy that when the polysilicon gate is at zero bias, The lightly doped semiconductor region of the first conductivity type is completely depleted by the second conductivity type semiconductor region; the present invention improves the maximum turn-off current of the gate-controlled thyristor device, effectively prevents shutdown failure, and improves the reliability of the gate-controlled thyristor device sex.

Description

technical field [0001] The invention relates to the technical field of semiconductor devices, in particular to a gate-controlled thyristor device with improved turn-off characteristics. Background technique [0002] With the continuous development of human society, energy consumption continues to increase, while increasing energy output, there are also higher and higher requirements for energy utilization. The realization of these requirements depends on the development of power electronic devices. As a new semiconductor power switching device, MOS gate-controlled thyristor has attracted more and more people's attention. [0003] figure 1 Shown is a schematic structural diagram of a traditional N-type gate-controlled thyristor. Gate-controlled thyristor (MOS Controlled Thyristor, MCT) is a composite power device that combines the characteristics of MOSFET and thyristor. It also has high input impedance of MOSFET, fast switching speed, convenient gate control and high bloc...

AI Technical Summary

Problems solved by technology

However, since the traditional gate-controlled thyristor manufacturing process is based on the triple diffusion process of DMOS technology, the P well and N well on the cathode side are formed by implantation and diffusion, so the doping concentration of the N well is usually greater than that of the P well. , the adjustable range is very small, so adjusting the doping concentration of the N well cannot effectively reduce the threshold voltage of the OFF-FET

Therefore, the traditional gate-controlled thyristor structure cannot effectively reduce the threshold voltage of the OFF-FET

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