Measurement of band offsets and interface charges by the C–V matching method
30 Jun 1998-Journal of Applied Physics (American Institute of Physics)-Vol. 84, Iss: 2, pp 1113-1120
TL;DR: In this paper, a novel application of capacitance-voltage measurements to determine simultaneously the band discontinuities (ΔEV, ΔEC) and interface charge density (σ) of heterojunctions is described.
Abstract: The present article describes a novel application of capacitance–voltage measurements to determine simultaneously the band discontinuities (ΔEV, ΔEC) and interface charge density (σ) of heterojunctions. The method, which we refer to as C–V matching, complements the most versatile C–V profiling technique proposed by Kroemer and successfully applied by others. In contrast to the C–V profiling which is limited to isotype heterojunctions, the new method is applicable to p-n heterojunctions as well. The methodology is based on three cardinal equations which are not controversial—the lineup of the bands relative to the common Fermi level (at equilibrium) or the quasi-Fermi levels (when voltage is applied), the charge neutrality and the expression for the total capacitance of the heterostructure. The three equations are formulated for equilibrium as well as nonequilibrium conditions, using quasi-Fermi levels and the quasi-equilibrium approximation. The three cardinal equations are defined by the two constant (al...
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TL;DR: This list of features and measurements of ALI is intended as a guide for investigators, and ultimately investigators should choose the particular measurements that best suit the experimental questions being addressed as well as take into consideration any unique aspects of the experimental design.
Abstract: Acute lung injury (ALI) is well defined in humans, but there is no agreement as to the main features of acute lung injury in animal models. A Committee was organized to determine the main features that characterize ALI in animal models and to identify the most relevant methods to assess these features. We used a Delphi approach in which a series of questionnaires were distributed to a panel of experts in experimental lung injury. The Committee concluded that the main features of experimental ALI include histological evidence of tissue injury, alteration of the alveolar capillary barrier, presence of an inflammatory response, and evidence of physiological dysfunction; they recommended that, to determine if ALI has occurred, at least three of these four main features of ALI should be present. The Committee also identified key "very relevant" and "somewhat relevant" measurements for each of the main features of ALI and recommended the use of least one "very relevant" measurement and preferably one or two additional separate measurements to determine if a main feature of ALI is present. Finally, the Committee emphasized that not all of the measurements listed can or should be performed in every study, and that measurements not included in the list are by no means "irrelevant." Our list of features and measurements of ALI is intended as a guide for investigators, and ultimately investigators should choose the particular measurements that best suit the experimental questions being addressed as well as take into consideration any unique aspects of the experimental design.
1,243 citations
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TL;DR: A perspective on ventilator-induced lung injury is presented with a focus on mechanisms and clinical implications, and some of the most recent findings are highlighted, which are believed to contribute to the generation and propagation of ventilated lung injury.
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460 citations
TL;DR: This review examines the seminal bench and bedside studies that contributed to the authors' current understanding of VILI, and that form the basis for current recommendations for mechanical ventilation of the critically ill.
Abstract: Once upon a time the existence of ventilator-induced lung injury (VILI) was debated. After all, most patients with lung dysfunction requiring mechanical ventilation had other potential causes of lung injury, and many patients appeared to tolerate mechanical ventilation for prolonged periods without any adverse sequelae. However, as a result of numerous studies over the past century, and especially during the past 20 years it is now generally accepted that mechanical ventilation per se can initiate as well as exacerbate lung injury and contribute to patient morbidity and mortality. This review examines the seminal bench and bedside studies that contributed to our current understanding of VILI, and that form the basis for current recommendations for mechanical ventilation of the critically ill. Figure 1 schematically depicts a timeline of bench to bedside research on VILI. Included in this review are many of the most frequently cited studies (with the number of citations, N, from the Institute for Science Information Citation Index as of August 2005 included in parentheses), as well as those studies which the authors feel have had a particularly significant impact on subsequent research and/or clinical practice.
382 citations
TL;DR: These studies confirm in humans that high capillary pressure induces a high-permeability-type lung edema in the absence of inflammation, a concept first introduced under the term "stress failure."
Abstract: High-altitude pulmonary edema (HAPE) develops in rapidly ascending nonacclimatized healthy individuals at altitudes above 3,000 m. An excessive rise in pulmonary artery pressure (PAP) preceding ede...
319 citations
References
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TL;DR: In this article, the conduction band edge discontinuity ΔEc = 0.56 eV at n−CdS/p−InP junctions is reported, and the performance of this discontinuity and others are compared with photoemission data and with Van Vechten's extension of these data to many tetrahedrally coordinated semiconductors.
Abstract: The discontinuity ΔEc=0.56 eV in the conduction band edge at n‐CdS/p‐InP junctions is reported. This discontinuity and others are compared with photoemission data and with Van Vechten’s extension of these data to many tetrahedrally coordinated semiconductors. Agreement between measured discontinuities and theoretical predictions is very good. Predictions are made for band parameters pertinent to interfaces involving AIIBIVCV2 compounds with zinc blende, chalcopyrite, or wurtzite crystal structures.
208 citations
IBM1
TL;DR: In this paper, the common-anion rule is examined and predicted to fail for all lattice-matched II-VI and III-V heterojunctions, including HgTe-CdTe.
Abstract: Band-edge discontinuities are calculated for tellurium-based II-VI heterojunctions. Contrary to the widely accepted common-anion rule, large valence-band discontinuities are found in most cases, including HgTe-CdTe. The common-anion rule is examined and predicted to fail, not only here, but for all lattice-matched II-VI and III-V heterojunctions. An experiment is proposed to test these predictions.
194 citations
Book•
19 Jan 2012
TL;DR: In this paper, the authors discuss the structural defects in narrow-gap II-VI semiconductors and their application in various applications, including photoconductive detectors in HgCdTe and related alloys.
Abstract: Part One: Growth techniques. Bulk growth techniques. Liquid phase epitaxy. Metal-organic vap our phase epitaxy. Molecular beam epitaxy of HgCdTe. Part Two: Materials characterisation. Optical properties of MCT. Transport properties of narrow-gap II-VI compounds. Intrinsic and extrinsic doping. Point defects in narrow-gap II-VI compounds. Diffusion in narrow-gap II-VI compounds. Surfaces/interfaces of narrow-gap II-VI compounds. Trends in structural defects in narrow-gap II-VI semiconductors. Quantum wells and superlattices. Properties of diluted magnetic semiconductors. Part Three: Device applications. Photoconductive detectors in HgCdTe and related alloys. Photovoltaic IR detectors. Non-equilibrium devices in HgCdTe. Emission devices. Photoelectromagnetic, magnetoconcentration and Dember infrared detecors. Solar cells based on CdTe. Radiation detectors. Index.
92 citations