深亚微米工艺中场氧器件静电防护能力的研究

研究了FOD在输入、输出和电源箝位部分ESD的工作特点,在0.18μm5V EEPROM CMOS工艺下流片、测试并分析了针对输入、输出和电源箝位的三种主流的ESD保护FOD器件,通过传输线脉冲测试仪的测量,重点分析了特征尺寸对器件ESD特性的影响及其设计方法。结果表明:影响FOD的ESD性能的主要因素是沟道长度、漏极长度和漏极接触孔到有源区的距离;增加沟道长,可适当提高FOD的ESD开启电压,但是会降低ESD防护性能;增加FOD的漏极长度和漏极接触孔到有源区的距离,可以提高FOD的ESD防护性能。提出了一种新型的浮体多晶硅岛屿型FOD结构,该结构不但结构简单,而且具有良好的ESD防护性能。

FOD Based ESD Protection Devices in Deep Sub-micron Technology

Field oxide devices (FOD) based ESD (Electrostatic discharge) protection devices are investigated in this paper. According to different protected parts of IC chip such as input,output and power rails,three main FOD devices are fabricated in 0.18 μm EEPROM silicide CMOS technology. By using TLP tester,the effects of the feature size on FOD's ESD characteristics and its design rule are analyzed. Results show that channel length and the distance between drain and contact (DCG) play a vital role. With increasing the channel length,trigger voltage is enhanced,but ESD robustness is weakened. Increasing DCG can enhance FOD ESD protection ability. A floating square poly island FOD is presented in this paper,which shows a simple structure and good ESD protection ability.