A. Deyine, THALES & CNES (French Space Agency) laboratory, Toulouse, France

Summary: Dynamic Laser Stimulation (DLS) localization techniques are now commonly used in failure analyse laboratory. They proved to be very accurate, efficient and they evolve to be adapted to new defects emergence due to miniaturization. All the lasers based techniques suppose that we are able to identify sensitive operating parameters to work on: delay, frequency, power etc. Actually, we don’t always have this access. We need other means when we deal with “stuck at” problems in dynamic mode for instance. The idea to solve this issue comes from the world of security testing. In his paper, Skorobogatov demonstrated the efficiency of optical probe combining with a power analysis to study attack in cryptographic algorithm. Indeed we know that the technique like OBIC (LIVA) allow detecting transistor transitions between two states: opened and closed. In failure analysis we can use the power analysis combining with a photovoltaic effect to localize ”stuck at” which appears in dynamic mode. We will compare the current signature between a golden device and a device with a “stuck at” problem. By monitoring the power variation and correlating the results with the laser beam position we can pinpoint defective structures.