一种多电源域专用数字电路的静电失效分析及提升研究

在静电放电(ESD)能力考核时,一种多电源域专用数字电路在人体模型(HBM)1 700 V时失效。通过HBM测试、激光束电阻异常侦测(OBIRCH)失效分析方法,定位出静电试验后失效位置。根据失效分析结果并结合理论分析,失效是静电二极管的反向静电能力弱所致。利用晶体管替换静电二极管,并对OUT2端口的内部进行静电版图优化设计。改版后,该电路的ESD防护能力达2 500 V以上。该项研究结果对于多电源域专用数字电路的ESD失效分析及能力提升具有参考价值。

ESD Failure Analysis and Improvement of a Special Digital Circuit for Multi-Power Supply Domain

In the test of electrostatic discharge (ESD) capacity, a special digital circuit for multi-power domain failed at 1 700 V of the human body model (HBM). The failure position after electrostatic test was located by the HBM test and the optical beam induced resistance change (OBIRCH) failure analysis. According to the failure analysis results and theoretical analysis, the reason was due to weak reverse electrostatic capacity of the electrostatic diode. The transistors were used to replace the electrostatic diodes, and the interior of OUT2 port was optimized for electrostatic layout design. After the revision, the ESD protection capability of the circuit reached more than 2 500 V. The results of this study had reference value for ESD failure analysis and robustness improvement of multi-power supply domain digital circuits.