This article reviews recent developments in the area of molecular-scale computing. It describes the construction and operating characteristics of molecular wires, rectifiers, switches, and transistors. It also discusses the concept of molecular gain. Molecular computing architectures based on crosspoint arrays, randomized nanocells, and cellular automata will be discussed in Part II of this article in the November 2004 issue of EDFA .

This is the second part of an article on molecular electronics. The first part, published in the August 2004 issue of EDFA , discussed the development of molecular devices including nanowires, rectifiers, switches, and transistors. Here, the author describes nontraditional molecular computing architectures based on crosspoint arrays, randomized nanocells, and cellular automata. Challenges associated with interconnect demand, lithography alternatives, and defect tolerance are also discussed.

This article examines current research into the building blocks of the nanoscale system and the techniques used to synthesize them. Also explored are some proposed ideas and the challenges associated with integrating these building blocks into molecular nanosystems such as chemically assembled electronic nanocomputers (CAENs).

This article discusses the emergence of nanoelectronics and the effect it may have on semiconductor testing and failure analysis. It describes the different types of quantum effect and molecular electronic devices that have been produced, explaining how they are made, how they work, and the changes that may be required to manufacture and test these devices at scale.

The ability to place atoms one by one at specific atomic sites was first used to create functioning electronic devices in the late 1990s. Since then, the process known as atomic precision advanced manufacturing (APAM) has been further developed and both academic and commercial interest in its potential has grown. This article describes the nuances of the process, explaining that it places dopants into silicon using surface chemistry, a mechanism not typically used in microfabrication. It also discusses ongoing efforts to develop more complex quantum devices using APAM techniques and outlines the challenges involved in interfacing APAM and CMOS devices on the same die.

Scanning microwave impedance microscopy is a nearfield technique using microwaves to probe the electrical properties of materials with nanoscale lateral resolution.

Several failure analysis case studies have been conducted over the past few years, illustrating the importance of preserving root-cause evidence by means of artifact-free decapsulation. The findings from three of those studies are presented in this article. In one case, the root cause of failure is chlorine contamination. In another, it is a combination of corrosion and metal migration. The third case involves an EOS failure, the evidence of which was hidden under a layer of carbonized mold compound. In addition to case studies, the article also includes images that compare the results of different decapsulation methods.

Flat-panel X-ray detectors used in medical imaging applications present a challenge to failure analysts due to the scale of the products, the newness of the technology, and the relatively low production rates compared to ICs. This article explains how existing tools are being adapted to accommodate the size of these detectors and the exotic materials from which they are made. It discusses the types of defects that can occur and how they affect critical detector characteristics. It describes the basic approach for defect localization and physical analysis and presents examples of defects in different areas of a flat-panel X-ray detector.

New materials integration and improved design can be promoted by using atom probe tomography (APT) as an analysis technique. This article provides an overview of APT principles and setups and provides diverse examples that focus on its use to characterize electronic devices.

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.

This article provides an overview of atom probe tomography (APT) and its use in semiconductor FA and new product development. It discusses the basic components in an atom probe, the making of APT tips, and the general approach for data collection and reconstruction. It also includes a case study in which 3D atom probe techniques are used to map dopant profiles and identify defects in the source-drain region of SiGe FinFET transistors.

The 47th International Symposium for Testing and Failure Analysis (ISTFA 2021) was held in Phoenix, Ariz., from October 31 to November 4, 2011. This article provides a summary of the keynote presentation, technical program, panel discussion, tutorials, User Group meetings, and the Women in Electronics Failure Analysis (WEFA) event.