SCR for electrostatic protection, chip and system

Abstract

The invention provides a semiconductor controlled rectifier (SCR) for electrostatic protection, a chip and a system, relates to the electronic technology field and can realize start voltage reduction and maintenance voltage improvement. The SCR comprises a semiconductor substrate, and a first well, a second well and a third well which are arranged on the semiconductor substrate, wherein conductive types of the first well and the third well are identical, the second well is in a different conductive type, the first well is internally provided with a first heavily doped region and a second heavily doped region, the first heavily doped region and the second heavily doped region are different in conductive types, the first heavily doped region and the first well are identical in conductive types, the third well is internally provided with a third heavily doped region, the third heavily doped region and the third well are identical in conductive types, the second well is internally provided with a fourth heavily doped region, the four heavily doped region and the second well are identical in conductive types, the fourth heavily doped region extends to the first well and the third well, a first gap is arranged between the fourth heavily doped region and the second heavily doped region, and a metal gate is arranged at the first gap.

Description

technical field [0001] The present application relates to the field of electronic technology, in particular to an SCR, a chip and a system for electrostatic protection. Background technique [0002] Electrostatic Discharge (ESD) is a common natural phenomenon in our life, but the large current generated by ESD in a short period of time can cause fatal damage to integrated circuits (Integrated Circuit, IC). For example, for the electrostatic discharge phenomenon (Human-Body Model, HBM) that occurs in the human body, it usually occurs within hundreds of nanoseconds, and the maximum current peak value may reach several amperes. Some other modes, such as machine discharge mode (MachineModel, MM) and component charging mode (Charged-Device Model, CDM), have shorter electrostatic discharge time and larger current. Such a large current passes through the IC in a short time, and the power consumption generated will seriously exceed the maximum value it can withstand, which will cau...

AI Technical Summary

Problems solved by technology

This improvement can reduce the turn-on voltage to about 12V and maintain the voltage at about 1.5V (such as Figure 4 As shown), but still can not meet these protocol interfaces such as High Definition Multimedia Interface (High Definition Multimedia Interface, HDMI), Universal Serial Bus (Universal Serial Bus, USB), Video Interface (Video-By-One, VBO) etc. needs

Because, on the one hand, the power supply voltage of these interfaces is generally around 3.3V, and the maintenance voltage of 1.5V is much lower than 3.3V, which will cause latch-up effect; on the other hand, the additional board-level transient suppression (Transient Voltage The turn-on voltage of the Suppressor (TVS) diode is about 8-10V, and the turn-on voltage of 12V cannot effectively reduce the impact or even damage of the internal circuit caused by static electricity.

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