Ionic liquids are remarkable chemical compounds, which find applications in many areas of modern science. Because of their highly tunable nature and exceptional properties, ionic liquids have become essential players in the fields of synthesis and catalysis, extraction, electrochemistry, analytics, biotechnology, etc. Apart from physical and chemical features of ionic liquids, their high biological activity has been attracting significant attention from biochemists, ecologists, and medical scientists. This Review is dedicated to biological activities of ionic liquids, with a special emphasis on their potential employment in pharmaceutics and medicine. The accumulated data on the biological activity of ionic liquids, including their antimicrobial and cytotoxic properties, are discussed in view of possible applications in drug synthesis and drug delivery systems. Dedicated attention is given to a novel active pharmaceutical ingredient-ionic liquid (API-IL) concept, which suggests using traditional drugs in ...

Biological Activity of Ionic Liquids and Their Application in Pharmaceutics and Medicine.

Detecting target analytes with high specificity and sensitivity in any fluid is of fundamental importance to analytical science and technology. Surface-enhanced Raman scattering (SERS) has proven to be capable of detecting single molecules with high specificity, but achieving single-molecule sensitivity in any highly diluted solutions remains a challenge. Here we demonstrate a universal platform that allows for the enrichment and delivery of analytes into the SERS-sensitive sites in both aqueous and nonaqueous fluids, and its subsequent quantitative detection of Rhodamine 6G (R6G) down to ∼75 fM level (10(-15) mol⋅L(-1)). Our platform, termed slippery liquid-infused porous surface-enhanced Raman scattering (SLIPSERS), is based on a slippery, omniphobic substrate that enables the complete concentration of analytes and SERS substrates (e.g., Au nanoparticles) within an evaporating liquid droplet. Combining our SLIPSERS platform with a SERS mapping technique, we have systematically quantified the probability, p(c), of detecting R6G molecules at concentrations c ranging from 750 fM (p > 90%) down to 75 aM (10(-18) mol⋅L(-1)) levels (p ≤ 1.4%). The ability to detect analytes down to attomolar level is the lowest limit of detection for any SERS-based detection reported thus far. We have shown that analytes present in liquid, solid, or air phases can be extracted using a suitable liquid solvent and subsequently detected through SLIPSERS. Based on this platform, we have further demonstrated ultrasensitive detection of chemical and biological molecules as well as environmental contaminants within a broad range of common fluids for potential applications related to analytical chemistry, molecular diagnostics, environmental monitoring, and national security.

https://www.pnas.org/content/pnas/113/2/268.full.pdf

Ultrasensitive surface-enhanced Raman scattering detection in common fluids

The field of flexible electronics has rapidly expanded over the last decades, pioneering novel applications, such as wearable and textile integrated devices, seamless and embedded patch-like systems, soft electronic skins, as well as imperceptible and transient implants. The possibility to revolutionize our daily life with such disruptive appliances has fueled the quest for electronic devices which yield good electrical and mechanical performance and are at the same time light-weight, transparent, conformable, stretchable, and even biodegradable. Flexible metal oxide semiconductor thin-film transistors (TFTs) can fulfill all these requirements and are therefore considered the most promising technology for tomorrow's electronics. This review reflects the establishment of flexible metal oxide semiconductor TFTs, from the development of single devices, large-area circuits, up to entirely integrated systems. First, an introduction on metal oxide semiconductor TFTs is given, where the history of the field is revisited, the TFT configurations and operating principles are presented, and the main issues and technological challenges faced in the area are analyzed. Then, the recent advances achieved for flexible n-type metal oxide semiconductor TFTs manufactured by physical vapor deposition methods and solution-processing techniques are summarized. In particular, the ability of flexible metal oxide semiconductor TFTs to combine low temperature fabrication, high carrier mobility, large frequency operation, extreme mechanical bendability, together with transparency, conformability, stretchability, and water dissolubility is shown. Afterward, a detailed analysis of the most promising metal oxide semiconducting materials developed to realize the state-of-the-art flexible p-type TFTs is given. Next, the recent progresses obtained for flexible metal oxide semiconductor-based electronic circuits, realized with both unipolar and complementary technology, are reported. In particular, the realization of large-area digital circuitry like flexible near field communication tags and analog integrated circuits such as bendable operational amplifiers is presented. The last topic of this review is devoted for emerging flexible electronic systems, from foldable displays, power transmission elements to integrated systems for large-area sensing and data storage and transmission. Finally, the conclusions are drawn and an outlook over the field with a prediction for the future is provided.

/pdf/metal-oxide-semiconductor-thin-film-transistors-for-flexible-16f7s8g8at.pdf

Metal oxide semiconductor thin-film transistors for flexible electronics

https://www.iue.tuwien.ac.at/pdf/ib_2011/JB2011_Grasser_5.pdf

Stochastic charge trapping in oxides: From random telegraph noise to bias temperature instabilities

One of the most important degradation modes in CMOS technologies, the bias temperature instability (BTI) has been known since the 1960s. Already in early interpretations, charge trapping in the oxide was considered an important aspect of the degradation. In their 1977 paper, Jeppson and Svensson suggested a hydrogen-diffusion controlled mechanism for the creation of interface states. Their reaction-diffusion model subsequently became the dominant explanation of the phenomenon. While Jeppson and Svensson gave a preliminary study of the recovery of the degradation, this issue received only limited attention for many years. In the last decade, however, a large number of detailed recovery studies have been published, showing clearly that the reaction-diffusion mechanism is inconsistent with the data. As a consequence, the research focus shifted back toward charge trapping. Currently available advanced charge-trapping theories based on switching oxide traps are now able to explain the bulk of the experimental data. We give a review of our perspective on some selected developments in this area.

The Paradigm Shift in Understanding the Bias Temperature Instability: From Reaction–Diffusion to Switching Oxide Traps

Sensors Joseph E. Reiner,*,† Arvind Balijepalli,‡,§ Joseph W. F. Robertson,‡ Jason Campbell,‡ John Suehle,‡ and John J. Kasianowicz‡ †Department of Physics, Virginia Commonwealth University, 701 W. Grace Street, Richmond, Virginia 23284, United States ‡Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8120, United States Laboratory of Computational Biology, National Heart Lung and Blood Institute, Rockville, Maryland 20852, United States

Disease detection and management via single nanopore-based sensors.

Series resistance has become a serious obstacle inhibiting the performance of advanced CMOS devices. However, series resistance quantification in these same advanced CMOS devices is becoming exceedingly difficult. In this letter, we demonstrate a very simple series resistance extraction procedure which is derived only from the ratio of two linear ID-VG measurements. This approach has a verifiable accuracy check and is successfully used to extract the series resistance from several advanced devices. Furthermore, the validity of the assumptions used in this series resistance extraction procedure is examined and shown to be justified. In an attempt to further test the validity of this technique, several known external resistors were inserted in series with the device under test. The series resistance extraction procedure faithfully reproduces these known external resistances to within ±10%.

A Simple Series Resistance Extraction Methodology for Advanced CMOS Devices

Recently, 1/f and random telegraph noise (RTN) studies have been used to infer information about bulk dielectric defects' spatial and energetic distributions. These analyses rely on a noise framework which involves charge exchange between the inversion layer and the bulk dielectric defects via elastic tunneling. In this study, we extracted the characteristic capture and emission time constants from RTN in highly scaled nMOSFETs and showed that they are inconsistent with the elastic tunneling picture dictated by the physical thickness of the gate dielectric (1.4 nm). Consequently, our results suggest that an alternative model is required and that a large body of the recent RTN and 1/ƒ noise defect profiling literature very likely needs to be re-interpreted.

/pdf/random-telegraph-noise-in-highly-scaled-nmosfets-3mac93smhc.pdf

Random telegraph noise in highly scaled nMOSFETs

An electron spin resonance spectrometer includes a bridge to transmit an excitation frequency and to receive a signal frequency; a probe electrically connected to the bridge and comprising: a first conductor in electrical communication with the bridge to transmit the signal frequency to the bridge; a shorting member electrically connected to the first conductor to transmit the excitation frequency to a sample, to produce the signal frequency, and to transmit the signal frequency to the first conductor; and a second conductor electrically connected to the shorting member; and a magnet disposed proximate to the probe.

Electron spin resonance spectrometer and method for using same

One of the most serious technology roadblocks for SiC DMOSFETs is the significant occurrence of early failures in time-dependent-dielectric-breakdown testing. Conventional screening methods have proved ineffective, because the remaining population is still plagued with poor reliability. The traditional local thinning model for extrinsic (early) failures, which guides the screening through burn-in measures, simply does not work. The fact that improved cleanliness control in the fabrication process does little to reduce early failures also suggests that local thinning due to contamination is not the root cause. In this paper, we propose a new lucky defect model where bulk defects in the gate oxide, introduced during growth, are responsible for the early failures. We argue that a local increase in leakage current via trap-assisted tunneling leads to early oxide breakdown. This argument is supported with oxide breakdown observations in SiC/SiO2 DMOSFETs, as well as simulations that examine various defect distributions and their impact on the resultant early failure distributions.

Jason P. Campbell

Papers

Disease detection and management via single nanopore-based sensors.

A Simple Series Resistance Extraction Methodology for Advanced CMOS Devices

Random telegraph noise in highly scaled nMOSFETs

Electron spin resonance spectrometer and method for using same

Modeling Early Breakdown Failures of Gate Oxide in SiC Power MOSFETs