Challenges and Opportunities of Chemiresistors Based on Microelectromechanical Systems for Chemical Olfaction

Abstract

Microelectromechanical-system (MEMS)-based semiconductor gas sensors are considered one of the fastest-growing, interdisciplinary high technologies during the post-Moore era. Modern advancements within this arena include wearable electronics, Internet of Things, and artificial brain-inspired intelligence, among other modalities, thus bringing opportunities to drive MEMSbased gas sensors with higher performance, lower costs, and wider applicability. However, the high demand for miniature and micropower sensors with unified processes on a single chip imposes great challenges. This review focuses on recent developments and pitfalls in MEMS-based micro-and nanoscale gas sensors and details future trends. We also cover the background of the topic, seminal efforts, current applications and challenges, and opportunities for next-generation systems.

Effectively Enhancing the Conductance of Asymmetric Molecular Wires by Aligning the Energy Level and Symmetrizing the Coupling

“…1,2 With representation by the carbon−electrode junction, which is considered the most probable junction for commercially available molecular devices in the short term, 3 the stable junction commonly asks the molecules to be installed in the prefabricated gap between the electrodes, like a microelectromechanical system. 4 Fabricating such molecular junctions requires the molecule to exhibit not only appropriate conductance but also the ideal length to accommodate the gap. However, because the conductance of the molecules is very sensitive to the variation of molecular length as a result of the tunneling feature of electron transport in the molecule, the enhancement of conductance is usually caused by the shrinkage of molecular length.…”

Microelectromechanical Microsystems-Supported Photothermal Immunoassay for Point-of-Care Testing of Aflatoxin B1 in Foodstuff

“…Recently, along with the development of the internet of things (IOT) and electronic information technology, homemade or commercially available miniaturized devices based on different signal principles have aroused great interest among analytical chemists for the development of portable sensors. − A variety of signal readout methods based on smartphone adapters, MEMS platforms, and handheld multimeters have been reported due to portability and ease of operation. For example, Lee and his colleagues have developed a series of integrated biosensing platforms focused on serological analysis and diagnostics. − Low-cost, batch-producible MEMS sensing devices are expected to play an important role in the rapid detection of high-volume samples.…”

Single-Step PEDOT Deposition by oCVD for ITO-Free Deep Blue OLEDs

“…Organic light-emitting diodes (OLEDs) have led the way for display and lighting applications with their superior performance in terms of the color gamut and luminance efficiency. − This technology is widely used in everyday applications such as smartphones and digital cameras and is a potential candidate for the Internet of Things (IoT), e.g., temperature and humidity meters based on OLED displays. − Nevertheless, several challenges still need to be overcome to achieve even better devices with excellent output performances. One such challenge is to enhance the device architecture by reducing the number of layers that can lead to a high probability of photon trapping.…”