Practical experiences with the novel electron beam testing methods logic-state tracing, frequency tracing and frequency mapping

Five examples of chip verification and failure analysis applications are presented to demonstrate the effectiveness of three novel electron beam testing methods: logic-state tracing, frequency tracing and frequency mapping. The first two methods visualize all circuit structures carrying a sought-for bit pattern or signal frequency. In frequency mapping, a spectral analysis is carried out to determine unknown frequencies. These new methods are especially well suited for the investigation of high-frequency circuits, asynchronously operating circuits and for detecting signals at interconnections covered with isolating layers. (Auth.)