Selecting an Optimal Faraday Cage To Minimize Noise in Electrochemical Experiments

A Tutorial for Scanning Electrochemical Cell Microscopy (SECCM) Measurements: Step-by-Step Instructions, Visual Resources, and Guidance for First Experiments

Scanning electrochemical cell microscopy (SECCM) produces nanoscale-resolution electrochemical maps of electrode surfaces using the meniscus at the tip of an electrolyte-filled nanopipette as a mobile electrochemical cell. While the use and range of applications of SECCM have grown rapidly since its introduction, the pathway to performing SECCM measurements can be daunting to those without direct access to expert users. This work fills this expertise gap by providing a step-by-step guide to performing one's first SECCM experiments, including troubleshooting strategies, videos/images, suggested parameters and experimental systems, and representative data (of both successful experiments and common problems). No background in SECCM is assumed and fundamentals are clearly explained at each stage with a rationale for the experimental steps provided. This work provides an entry point for the uninitiated to understand and use this powerful nanoscale electrochemical characterization technique.

Preparation of Silicon Nanopillar Arrays Using Reactive Ion Etching with a Faraday Cage

Faraday cages are extensively utilized in plasma-based etching and deposition processes to regulate ion behavior due to their shielding effect on electromagnetic fields. Herein, vertical silicon nanopillar arrays are fabricated through SF6 and O2 reactive ion etching. By incorporation of a Faraday cage in the plasma equipment, the impact of the Faraday cage on the morphology of the silicon nanopillars is analyzed; the Faraday cage blocks out the sputtered particles and eradicates the formation of silicon nanograss. Specifically, it regulates the value and dispersion of the etching rate by varying the mesh number and the distance from the grid wires to the sample surface. A "flattening belly" phenomenon of silicon nanopillars associated with the temperature is resolved using segmented multiple etching processes. This research contributes to an in-depth analysis of plasma etching using a Faraday cage as well as potential applications for silicon nanopillars.

From Material to Cameras: Low-Dimensional Photodetector Arrays on CMOS

The last two decades have witnessed a dramatic increase in research on low-dimensional material with exceptional optoelectronic properties. While low-dimensional materials offer exciting new opportunities for imaging, their integration in practical applications has been slow. In fact, most existing reports are based on single-pixel devices that cannot rival the quantity and quality of information provided by massively parallelized mega-pixel imagers based on complementary metal-oxide semiconductor (CMOS) readout electronics. The first goal of this review is to present new opportunities in producing high-resolution cameras using these new materials. New photodetection methods and materials in the field are presented, and the challenges involved in their integration on CMOS chips for making high-resolution cameras are discussed. Practical approaches are then presented to address these challenges and methods to integrate low-dimensional material on CMOS. It is also shown that such integrations could be used for ultra-low noise and massively parallel testing of new material and devices. The second goal of this review is to present the colossal untapped potential of low-dimensional material in enabling the next-generation of low-cost and high-performance cameras. It is proposed that low-dimensional materials have the natural ability to create excellent bio-inspired artificial imaging systems with unique features such as in-pixel computing, multi-band imaging, and curved retinas.