ESD应力下n阱扩散电阻的潜在损伤

Latent damage in n-well diffused resistor under ESD stress

电阻在静电放电(Electrostatic Discharge,ESD)保护电路中,起隔离和分压的作用。利用传输线脉冲(Transmission Line Pulsing,TLP)测试系统,在宽度为100ns的脉冲作用下,研究了n阱扩散电阻在ESD应力下的工作特性。结果表明,n阱扩散电阻在发生初次瞬态击穿(瞬态击穿电压79.0V,瞬态击穿电流1.97A)后,由于阳极n+-n结构被破坏,内部结构已经出现潜在损伤,不再具备隔离和分压的作用。

ESD protection circuit, which is commonly used in the integrated circuit, becomes more and more important with the development of deep sub-micron integrated circuit. In the ESD protection circuit, the main functions of resistor are isolation and voltage limitation. The performance of n-well diffused resistor under ESD stress was evaluated using the transmission line pulsing （TLP） measurement system in the condition of lOOns pulses. Test results show that, after the first transient breakdown occurring in the n-well diffused resistor at 79.0V and 1.97A, latent damage is present in the resistor as a result of the breakage of n^＋-n junction at the anode. And the isolation as well as voltage limitation effects of diffused resistor disappear.