Four-dimensional scanning transmission electron microscopy (4D-STEM) is a spatially resolved electron diffraction technique that records the electron scattering distribution at each point of the electron beam raster, thereby producing a four-dimensional dataset. The final article in this series covers ptychography, a form of computational imaging that recovers the phase information imparted to an electron beam as it interacts with a specimen.

X-ray ptychography, as recent studies show, has the potential to bridge the gap that currently exists between conventional X-ray imaging and electron microscopy. This article covers the evolution of the technology from basic 2D imaging to computed tomography to 3D ptychographic X-ray laminography (PyXL) with zoom. To demonstrate the capabilities of PyXL, a 16-nm FinFET logic IC was mechanically polished to a thickness of 20 µm and several regions were imaged at various levels of resolution.

This column discusses the potential benefits of developing a dedicated synchrotron-based tool suite for advanced, high-throughput characterization, deprocessing, and validation of ICs.

This article provides a brief overview of STEM-in-SEM, discussing the pros and cons, recent advancements in detector technology, and the emergence of 4D STEM-in-SEM, a relatively new method that uses diffraction patterns recorded at different raster positions to enhance images offline in selected regions of interest.

Integrated circuits embedded in everyday devices face an increased risk of tampering and intrusion. In this article, the authors explain how reverse engineering techniques, including automated image analysis, can be employed to provide trust and assurance when dealing with commercial off-the-shelf chips.

The high energy-resolving power of superconducting x-ray detectors reduces unwanted x-ray backgrounds, uses x-ray photons efficiently, and allows for discrimination among multiple chemical elements in a sample. This article discusses the challenges of analyzing the internal structure and composition of integrated circuits, and how 3D imaging can benefit manufacturers and researchers. It covers the development of superconducting x-ray sensors, their advantages over traditional sensors, potential applications, and focus areas for future work to develop this technology.

This article presents a comprehensive study of physical inspection and attack methods, describing the approaches typically used by counterfeiters and adversaries as well as the risks and threats created. It also explains how physical inspection methods can serve as trust verification tools and provides practical guidelines for making hardware more secure.

Four-dimensional scanning transmission electron microscopy (4D-STEM) is a spatially resolved electron diffraction technique that records the electron scattering distribution at each point of the electron beam raster, thereby producing a four-dimensional dataset. This second installment of this series presents applications of 4D-STEM, including measurements of crystal orientation and phase, short- and medium-range order, and internal electromagnetic fields.