Noninvasive optical method and system for inspecting or testing CMOS circuits

A system for testing an integrated circuit, comprising:

• means for obtaining periodic optical emissions over a defined period of time and from a defined area of an integrated circuit operating with time-varying internal currents;
• means for time-resolving said emissions by photon timing to estimate the number of switching events occurring in said defined area over said defined period;
• means for providing an optical emission model;
• and
• means for comparing the optical emission from the area of the integrated circuit with the optical emission model to determine whether any of a group of defined conditions are present in the integrated circuit.

A program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform method steps for testing an integrated circuit, said method steps comprising:

• obtaining periodic optical emissions over a defined period of time and from a defined area of an integrated circuit operating with time-varying internal currents;
• time-resolving said emissions by photon timing to estimate the number of switching events occurring in said defined area over said defined period;
• providing an optical emission model;
• and
• comparing the optical emission from the area of the integrated circuit with the optical emission model to determine whether any of a group of defined conditions are present in the integrated circuit.