Failure Analysis on Diode-triggered Silicon-Controlled Rectifiers By using Nondestructive X-ray Microscopy

As the complexity of integrated circuits increases, the electrostatic discharge (ESD) protection devices become critical to reliability issues. However, the physical failure analysis of ESD devices is destructive and time-consuming. In this work, by using the X-ray microscopy (XRM), we study the abnormal change in the leakage current of diode-triggered silicon-controlled rectifiers (DTSCRs) ESD structure under transmission line pulsing stressing. XRM is nondestructive physical failure analysis method by showing the in-depth morphology information of the devices. The results show that the proposed ESD devices have two parts, one is the trigger diodes part and the other is the SCR part. The SCR part was severely damaged and the contact and vias are melted under the electrical stressing, while the trigger diodes part remains intact. The failure analysis is nondestructive, multi-view, and time-saving. It is enlightening the design of novel ESD devices.