Gate control silicon controlled rectifier device with improved turn-off characteristic

Abstract

The invention provides a gate control silicon controlled rectifier device with improved turn-off characteristic. The device includes a metalized anode, a first conducting type semiconductor substrate, a second conducting type semiconductor epitaxial layer and a metalized cathode stacked successively from bottom up. The device also includes a first conducting type semiconductor well region, a second conducting type semiconductor well region, a heavy doping first conducting type semiconductor zone and a gate structure. Only one side of the second conducting type semiconductor well region is provided with a light doping first conducting type semiconductor zone. The lower surface of the light doping first conducting type semiconductor zone is in contact with the first conducting type semiconductor well region. When the doping concentration and the widthof the light doping first conducting type semiconductor zone meets requirements for zero-bias of a polycrystalline silicon gate, the light doping first conducting type semiconductor zone is totally depleted by the second conducting type semiconductor well region. According to the invention, the maximal turn-off current of the gate control silicon controlled rectifier device is increased. At the same time, turn-off failure is prevented effectively and reliability of the gate control silicon controlled rectifier device is improved.

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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