This paper describes optical and electron beam based fault isolation approaches for short and open defects in nanometer-scale through-silicon via (TSV) interconnects. Short defects are localized by photon emission microscopy (PEM) and optical beam-induced current (OBIC) techniques, and open defects are isolated by active voltage contrast imaging in a scanning electron microscope (SEM). The results are confirmed by transmission electron microscopy (TEM) cross-sectioning.

This paper presents novel optical beam-based defect localization approaches for resistive and open failed wafer-towafer (W2W) bonding interconnects for 3-D integration. The use of an etch back process in combination with thermal laser stimulation (TLS) and light-induced capacitance alteration (LICA) using visible laser excitation enables us to accurately pinpoint defects in high-density W2W interconnect structures down to a pitch of 2.2 µm. We confirm our results by focusedion beam (FIB) cross sectioning.

We report on a new non-destructive electrical fault isolation (EFI) technique to localize interconnection failures in through-silicon via (TSV) structures for three-dimensional (3-D) integration. The scanning optical microscopy (SOM) technique is based on light-induced capacitance alteration (LICA) and uses localized photon probing of TSV interconnect capacitance to localize interruptions of electrical connectivity. The technique is applicable to passivated devices and allows rapid, efficient, and non-destructive fault isolation at wafer level. We describe the physics behind signal generation of the technique and demonstrate the TSV photocapacitance effect. We further demonstrate the LICA technique on open failed TSV daisy chain structures and confirm our results with microprobing and voltage contrast measurements in a scanning electron microscope (SEM).