Non-Destructive 3D Failure Analysis Work Flow for Electrical Failure Analysis in Complex 2.5D-Based Devices Combining 3D Magnetic Field Imaging and 3D X-Ray Microscopy

Abstract

Industry and market requirements keep imposing demands in terms of tighter transistor packing, die and component real estate management on the package, faster connections and expanding functionality. This has forced the semiconductor industry to look for novel packaging approaches to allow for 3D stacking of transistors (the so called “More than Moore”). This complex 3D geometry, with an abundance of opaque layers and interconnects, presents a great challenge for failure analysis (FA). Three-dimensional (3D) magnetic field imaging (MFI) has proven to be a natural, useful technique for non-destructively mapping 3D current paths in devices that allows for submicron vertical resolution. 3D X-ray microscopy (XRM) enables 3D tomographic imaging of advanced IC packages without the need to destroy the device. This is because it employs both geometric and optical image magnifications to achieve high spatial resolution. In this paper, we propose a fully nondestructive, 3D-capable workflow for FA comprising 3D MFI and 3D XRM. We present an application of this novel workflow to 3D defect localization in a complex 2.5D device combining high bandwidth memory (HBM) devices and an application specific integrated circuit (ASIC) unit on a Si interposer with a signal pin electrical short failure.

X‐ray microscopy and automatic detection of defects in through silicon vias in three‐dimensional integrated circuits

“…17,19 Therefore, XRM is used in R&D and in industrialization processes to inspect 3D ICs with TSVs on a regular basis to control and improve fabrication processes for metrological applications for process control, failure and defect localization in combination with other techniques or as a standalone investigation method. [19][20][21] One drawback of XRM, however, is the long measurement time that is required to image small micro-and nanometer sized cracks and voids inside the investigated samples. The measured voxel sizes are directly dependent on the investigated field of view, which depends mainly on the geometric and optical magnification of the system, resulting in a trade-off in resolution and the measured volume of the sample.…”

“…Therefore, XRM is used in R&D and in industrialization processes to inspect 3D ICs with TSVs on a regular basis to control and improve fabrication processes for metrological applications for process control, failure and defect localization in combination with other techniques or as a standalone investigation method 19‐21 . One drawback of XRM, however, is the long measurement time that is required to image small micro‐ and nanometer sized cracks and voids inside the investigated samples.…”

Magnetic field imaging and light induced capacitance alteration for failure analysis of Cu-TSV interconnects

“…The magnetic field passes unaffected through the different layers, not hindered by the RDL. MFI can detect the location of a current path, even for low currents, and can provide depth information [6,7]. Another option to obtain depth information would be https://doi.org/10.1016/j.microrel.2020.113780 Received 28 May 2020; Accepted 10 July 2020 attempting MFI from the cross-section.…”