Contactless, high-speed: Waveform measurements on gallium arsenide ICs

Abstract

Much progress has been made using photoemission testing. This type of testing compares favorably with results from electron-beam testing, particularly in terms of measurement time. The photoemission sampling system described here has a unique detector design and a viewer for the added convenience of the equipment operator. The authors report the performance results when this technique is used to measure delay and rise times on integrated gallium arsenide MESFET circuits. The switching time of these circuits is around 200 ps. The photoemission sampling system described here measures electrical pulses with an 8-ps rise time, so these GaAs circuits present no challenge. An interesting feature for special testing is the system' s ability to activate devices within a chip by a pulsed visible light beam. © 1990 IEEE