Novel image-based LSI diagnostic method using E-beam without CAD database

Novel voltage contrast image-based methods have been developed concerning voltage contrast image acquisition using electron beam tester and concerning fault searching on a VLSI chip, and have been applied to real faults of passivated VLSI devices. The developed voltage contrast image acquisition methods have shorten the acquisition time about 1200 times faster than that of the conventional stroboscopic methods and have given better image quality that that of conventional method. The method employed continuous e-beam scanning and gated sampling image signal technique (CGFI) technique. The continuous e-beam scanning may prevent the fading voltage contrast and give good voltage contrast image. The method also employed test vector shortening technique, which has a merit in shortening testing time and avoiding wrong fault tracing back