TSV fault contactless testing method based on group delay

Abstract

ABSTRACT As through silicon via (TSV) in three-dimensional (3-D) stacked integrated circuit (IC) has become micro-nanosized, the conventional wafer probe technology cannot fulfil the current detection requirements, so new testing techniques are urgently needed. In this paper, we present amethod for TSV contactless testing based on group delay. The group delay-based mixed testing stimulus is applied to the pending testing TSV through acontactless probe, and then output response is obtained by adetector. The crest factor (CF) is measured and calculated, and fault diagnosis is performed according to the CF difference between faultless and faulty TSV. The void fault of the signal-ground-TSV (SG-TSV) is also detected by the contactless testing method, and its fault function is obtained. The result shows that aresistive open circuit fault as small as several ohms can be detected through this approach. Finally, the fault testing resolution is improved by adjusting the modulation mode of the multi-tone signal.