Scanning TEM electron beam-induced current (STEM EBIC) imaging is a promising technique for providing high-resolution electronic and thermal contrast as a complement to TEM’s physical contrast. This article presents recent progress in using the focused ion beam (FIB) to prepare thin, electrically contacted cross-section samples for STEM EBIC imaging and in situ biasing. Techniques involving both standard Ga+ FIB and Xe+ plasma FIB (PFIB) are described.

Xenon plasma focused ion beam specimen preparation is ideal for preparing plan view TEM specimens due to its large-volume-milling capabilities. This article describes concentrated Ar ion beam milling using low energy as a post-pFIB final thinning step of plan view TEM specimens from a phase change memory device. Precise control of specimen thinning is achieved, which results in high-quality specimens with pristine surfaces and a large field of view for TEM characterization.

A scanning electron microscope system measures voltage contrast on device-under-test surfaces. This article addresses a limited set of applications that rely on voltage contrast (VC) measurements in SEM systems, showing how VC measurements can probe electrical activity running at speeds as high as 2 GHz on modern active integrated circuits.

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.

This article discusses the current state of large area integrated circuit deprocessing, the latest achievements in the development of automated deprocessing equipment, and the potential impact of advancements in gas-assisted etching, ion source alternatives, compact spectroscopy, and high-speed lasers.

This article discusses the advantages of SEM-based nanoprobing and the various ways it can be used to locate defects associated with IC failures. It describes the basic measurement physics of electron beam induced current, absorbed electron, and voltage distribution contrast imaging and presents examples showing how the different methods are used to isolate low- and high-resistance sites, shorts, and opens as well as ion implantation and metal patterning defects.

Dopant profiles in submicron silicon devices are typically measured using scanning probe techniques. A new SEM-based method has recently emerged, however, that could prove to be a more powerful tool for quantitative dopant imaging. This article discusses the measurement physics of secondary electron potential contrast imaging and assesses its capabilities based on the analysis of SiC power transistors, vertical cavity surface emitting lasers, and quantum well devices.

Voltage contrast followed by electron beam induced current imaging is an effective approach for isolating IC failures. This article briefly reviews the physics of signal generation for both techniques and presents several examples illustrating how this powerful combination contributes to advanced defect localization.

This article describes two innovative methods that can significantly improve the resolution of SEM imaging: scanning transmission electron microscopy in a scanning electron microscope (STEM-in-SEM) and forward-scattered electron imaging (FSEI). Both methods can be implemented in any SEM using special sample holders. No other modifications are required. Test results presented in the article show that 1 to 2 nm resolution is possible in thin sections, uncoated polysilicon gates, and photoresist.

STEM-EBIC imaging, a nano-characterization technique, has been used in the study of electrically active defects, minority carrier diffusion length, surface recombination velocity, and inhomogeneities in Si pn junctions. In this article, the authors explain how they developed and built a STEM-EBIC system, which they then used to determine the junction location of an InGaN quantum well LED. They also developed a novel FIB-based sample preparation method and a custom sample holder, facilitating the simultaneous collection of Z-contrast, EBIC, and energy dispersive spectroscopy images. The relative position of the pn junction with respect to the quantum well was found to be 19 ± 3 nm from the center of well.

Voltage contrast, a phenomenon that occurs in scanning electron microscopes, produces brightness variations in SEM images that correspond to potential variations on the test sample. Through appropriate processing, voltage contrast signals can reveal an extensive amount of information about the functionality of ICs. Voltage contrast can be used, for example, to map electrical logic levels and timing waveforms from internal nodes of the chip as it operates inside the SEM chamber. This article describes the fundamentals of voltage contrast and its applications in IC failure analysis.

Scanning electron microscopes (SEMs) are the dominant tool for electronic device testing, failure analysis, and characterization. This status was not apparent, however, when the first commercial SEM, the Cambridge Stereoscan, appeared in 1963. A market survey by the manufacturer at that time predicted total sales of six to ten units worldwide. For the last four decades, SEMs have sold at an average rate of one unit every 24 hours, with two out of every three instruments destined for the semiconductor industry.

Electron beam induced current (EBIC) analysis is a versatile tool that can be used by anyone with access to a SEM. This article explains how failure analysts are using the EBIC mode in SEMs to detect junction and oxide defects, simplify junction delineation, and reveal subsurface damage through multiple layers of metallization.

Scanning electron microscopes can be used to analyze almost anything that conducts electricity and is prone to failure, including relays, coils, inductors, capacitors, resistors, transistors, diodes, IGBTS, MOSFETS, and hybrid circuits. As the author of the article explains, SEMs are one of the most versatile tools for failure analysis if used to the full extent of their capabilities. Their operating modes include emissive imaging, backscattering, voltage contrast, EBIC or specimen current, and conductivity resistive mapping. The author describes each operating mode and presents examples of the various ways they can be used.