Energy and time-resolved photoemission in a promising new approach for contactless integrated-circuit testing

A novel approach to contactless measurement of voltages on internal nodes of integrated circuits is presented. The method is based on time-resolved photoemission exploiting the single-photon process with short laser pulses in the ultra-violet. The method allows spatial resolution in the submicron range given by the diffraction limit for UV photons, a time resolution of a few picoseconds given by the width of the laser pulses and the electron transit-time effect, and a voltage resolution of a few microvolts within a signal integration time of one second. © 1986.