Microscopic optical beam induced current measurements and their applications

The OBIC (Optical Beam Induced Current) system, which has been designed for detecting and analyzing the defect characteristics of the failed sample devices, is described with experimental results from defect characterizations of sample devices. Since a conforcal laser microscope has been adopted as a basic system, high spatial resolution power can be obtained, compared with an ordinary optical microscope. The detection limit of leakage current is improved up to 1 nA. Therefore, this system can reveal a number of semiconductor device phenomena such as defects of pn junctions, latch-up phenomena and the current leakage through the oxide layer by tunneling effect as well as by point contact. >