Transmission Line Pulse Testing of the ESD Protection Structures of ICs.- A Failure Analysts Perspective

The IC industry continues to find ways to improve the ability to correlate the electrical failure signature of devices with the physical failure location using different techniques. The purpose of this work is to show that improved transmission line pulse (TLP) testing technique of ESD (ElectroStatic Discharge) protection structures can provide accurate identification of leakage current to better identify where ESD stress testing should stop and failure analysis should begin. Besides the traditional current and voltage measurements at the Device Under Test (DUT), this new TLP testing technique includes the ability to correct for the measurement system losses for improved accuracy. The pulse width of the TLP is chosen to provide the same current amplitude damage level (electrical) as is found in the Human Body Model (HBM) ESD stress testing. This allows a one to one correlation between the two methods and hence the means to correlate the electrical damage of the device and the physical location of the failure site. An SCR (Silicon Controlled Rectifier) device is used as an example.