Open circuit defect positioning method based on dynamic photon emission microscopy and schematic analysis for mixed signal IC on SOI

Abstract

Failure analysis (FA) was encountered ion charging risk when using focused ion beam (FIB) to insert extra test pads for mixed signal integrated circuits (IC) on silicon-on-insulator (SOI). To overcome this challenge and to precisely locate the open circuit defect, this paper described an effective non-destructive FA method based on dynamic InGaAs photon emission microscopy and schematic/layout analysis to determine the open circuit type and position. Nano-probing and electron beam absorbed current (EBAC) was used to located the precise location of the open circuit defect. Two typical samples of mixed signal IC on SOI were used as examples (Sample 1 and 2, with extra and missing emission spots, respectively) to illustrate the analysis procedure and effectiveness for the proposed method. Scanning electron microscope (SEM) results were presented to verify the accuracy of this method. It was demonstrated that the proposed method was able to accurately determine failure of open circuit efficiently without microprobe for mixed signal IC on SOI.