Method and apparatus for identifying points on a specimen having a defined time-dependent signal

Abstract From the Canadian patent

A method for function checking microelectronic components inside LSI circuits, particularly during the development phase, provides localization and imaging of regions of a specimen which carry defined signals that depend on the operating status of the circuit. For localizing the points carrying the defined electrical signals a primary beam, reads the signal at the measuring point and a secondary signal derived therefrom is compared in a detector arrangement to the anticipated or sought-after signal by a correlation method. For the correlation the intensity of the primary beam or the current of the secondary particles are modulated alternately with the sought-after or anticipated signal and …