Scanning Capacitance Microscopy Application for Bipolar and CMOS Doping Issues in Semiconductor Failure Analysis

Scanning Capacitance Microscopy (SCM) has been extensively used for identifying doping issues in semiconductor failure analysis. In this paper, the root causes of two recent problems -- bipolar beta loss and CMOS power leakage -- were verified using SCM images. Another localization method, layer-by-layer circuit repair with IROBIRCH detection, was also utilized to locate possible defects. The resulting failure mechanism for bipolar beta loss is illustrated with a schematic cross section, which shows the leakage path from the emitter to the base. In the case of CMOS power leakage, the abnormal implantation of the Pwell region was identified with the Plane view SCM image.