Novel Failure Analysis Technique “Light Induced State Transition (LIST)” Method Using an OBIC System

Abstract

This paper describes a new technique, called the Light-Induced State Transition (LIST) method, that uses an optical beam induced current (OBIC) system for failure analysis of CMOS LSIs. This technique allows the user to locate a low signal line shortcircuited to a GND bus (or a high signal line shortcircuited to a VDD bus) in stand-by condition, which is not possible with conventional failure analysis techniques such as photo-emission analysis, liquid crystal technique, or the conventional OBIC method. The effectiveness of the LIST method was verified by a experiment on inverter chains that included quasi-failures intentionally patched by FIB deposition. The LIST method has also been used for actual CMOS failure analysis, and has proved useful for finding a failure location rapidly.