Abstract The usefulness of scattering-type near-field optical microscopy for mapping the material and doping in microelectronic devices at nanoscale resolution is demonstrated. Both amplitude and phase of infrared (λ = 10.7 μm) laser light scattered by a metallised, vibrating AFM tip scanned a few nanometers above the sample are detected and transformed into images showing contrast of materials, as well as of doping concentration. Cross-sections through layers as thin as 20 nm have been clearly imaged.

Abstract Effort and complexity for failure analysis are increasing on state of the art logic designs. As chips become more and more complex, functional tests are not possible anymore [1] and are replaced with automatic test pattern generation (ATPG) using a full scan design approach. Analysis of failing devices, however, becomes more complex as scan chains contain a large number of flip flops and localization of the failing net is a prerequisite for subsequent physical failure analysis (PFA). This becomes especially true for flip chip products, since access to the chip front side is not easily possible any more. This report describes the necessary failure analysis steps in order to identify the root cause of scan shift problems associated with two products fabricated in deep sub-micron technology