光控双向静电防护器件的建模分析与验证

Modeling Analysis and Verification of Light-Controlled Dual-Directional Electrostatic Protection Devices

利用光生伏特效应设计一种新型的光控双向栅极可控硅晶闸管(LDGSCR)防护器件,研究光照对静电放电(ESD)维持窗口的调控作用。使用光生电流来模拟光照控制ESD设计窗口的物理效应,实现一种光控器件的可控硅晶闸管(SCR)宏观模型。在1.5 V的电压模拟光照下,该模型的维持电流相比无光条件增加35 mA,表明使用光照来调整ESD的维持窗口可以降低被保护电路发生闩锁的风险。采用0.18μm BCD工艺制造LDGSCR器件并进行测试,测试结果与模型仿真结果之间的最大误差仅为0.09 V和0.004 A。验证表明,该宏观模型可以消除传统耦合晶体管电路模型中存在的收敛性问题,极大减少开发光控SCR器件新型结构所需的时间和精力。

A new type of light-controlled dual-directional gate silicon controlled rectifier(LDGSCR)protection device is designed by using the photovoltaic effect,and the regulation and control effect of light on the maintenance window of electrostatic discharge(ESD)is studied.The photo-generated current is used to simulate the physical effects of the light control ESD design window,and a macroscopic model of the silicon controlled rectifier(SCR)of the light control device is realized.Under the simulated illumination of 1.5 V voltage,the holding current of this model is increased by 35 mA compared to the no-light condition,indicating that the use of light to adjust the ESD maintenance window can reduce the risk of latch-up of the protected circuit.The LDGSCR device is fabricated and tested using a 0.18μm BCD process.The maximum error between the test result and the model simulation result is only 0.09 V and 0.004 A.The verification shows that the macro model can eliminate the convergence problems existing in the traditional coupled transistor circuit model,and greatly reduce the time and effort required to develop a new structure of light-controlled SCR devices.