Impact of semiconductors material on IR Laser Stimulation signal

In failure analysis laboratory, infrared laser stimulation techniques are more and more used for performing accurate defect localization on IC surface. Signatures obtained on metallic elements are well known, but weak data are available on signatures of semiconductors elements. Our investigations consist of studying impact of semiconductors materials on IR Laser Stimulation signal during a failure analysis. Frontside and backside Thermal Laser Stimulation (TLS) experiments were performed on n+/p+ diffusion and polycrystalline resistors from 0.18μm technology, both silicided (CoSi2) and unsilicided. Experimental results are presented and discussed for different W/L ratios. The impact of different semiconductors materials on TLS measurements is discussed and verified by experiment.