Ion-Assisted Processing of Electronic Materials

MRS Bulletin ◽  
1992 ◽  
Vol 17 (6) ◽  
pp. 23-25
Author(s):  
Walter L. Brown ◽  
Abbas Ourmazd
Keyword(s):  
Electronic Materials ◽  
Critical Role ◽  
The Past ◽  
Modern Process ◽  
Technological Potential ◽  
Fundamental Understanding ◽  
Materials Research ◽  
Realistic Assessment ◽  
Active Research

The fabrication of a state-of-the-art silicon chip consists of a carefully composed sequence of “steps.” The length, complexity, and place of each step within this process is analogous to that of a musical phrase within a long sonata. Just as a sonata consists of a series of recurring but evolving themes, a “process” utilizes a number of basic techniques that recur in a variety of contexts. A typical modern process consists of about 350 “steps.” Roughly a fifth of them belong to the class of ionassisted processing. These range from a variety of ion implantation modules, through sputter deposition and reactive ion etching of thin films, to photoresist etching and ashing. Ion-assisted processing thus has a role of major technological importance. With the range of new processes currently under active research, this trend seems likely to continue.The technological applications of ionassisted processing rest on the basic concepts developed in research over the past 30 years. This special issue of the MRS Bulletin reviews the fundamental concepts that underpin this processing today, and highlights areas of current research which may have future technological potential. The emphasis is placed heavily on silicon, both for illustrative purposes, and because Si processing is the major customer for ion-assisted technology. The articles pinpoint areas where materials research can play a critical role in establishing the fundamental understanding needed for a realistic assessment of technological potential.

Quantifying sources and sinks of trace gases using space-borne measurements: current and future science

2008 ◽  
Vol 366 (1885) ◽  
pp. 4509-4528 ◽  
Author(s):  
Paul I Palmer
Keyword(s):  
Trace Gases ◽  
Lower Troposphere ◽  
Biological Interactions ◽  
Satellite Measurements ◽  
Sources And Sinks ◽  
The Past ◽  
Fundamental Understanding ◽  
Earth’S Climate ◽  
New Generation

We have been observing the Earth's upper atmosphere from space for several decades, but only over the past decade has the necessary technology begun to match our desire to observe surface air pollutants and climate-relevant trace gases in the lower troposphere, where we live and breathe. A new generation of Earth-observing satellites, capable of probing the lower troposphere, are already orbiting hundreds of kilometres above the Earth's surface with several more ready for launch or in the planning stages. Consequently, this is one of the most exciting times for the Earth system scientists who study the countless current-day physical, chemical and biological interactions between the Earth's land, ocean and atmosphere. First, I briefly review the theory behind measuring the atmosphere from space, and how these data can be used to infer surface sources and sinks of trace gases. I then present some of the science highlights associated with these data and how they can be used to improve fundamental understanding of the Earth's climate system. I conclude the paper by discussing the future role of satellite measurements of tropospheric trace gases in mitigating surface air pollution and carbon trading.

scholarly journals CUL4A ubiquitin ligase: a promising drug target for cancer and other human diseases

Open Biology ◽  
2014 ◽  
Vol 4 (2) ◽  
pp. 130217 ◽  
Author(s):  
Puneet Sharma ◽  
Alo Nag
Keyword(s):  
Ubiquitin Ligase ◽  
Drug Target ◽  
Critical Role ◽  
Cellular Transformation ◽  
Biological Processes ◽  
Molecular Architecture ◽  
The Past ◽  
Cullin 4A ◽  
Broad Overview

The ability of cullin 4A (CUL4A), a scaffold protein, to recruit a repertoire of substrate adaptors allows it to assemble into distinct E3 ligase complexes to mediate turnover of key regulatory proteins. In the past decade, a considerable wealth of information has been generated regarding its biology, regulation, assembly, molecular architecture and novel functions. Importantly, unravelling of its association with multiple tumours and modulation by viral proteins establishes it as one of the key proteins that may play an important role in cellular transformation. Considering the role of its substrate in regulating the cell cycle and maintenance of genomic stability, understanding the detailed aspects of these processes will have significant consequences for the treatment of cancer and related diseases. This review is an effort to provide a broad overview of this multifaceted ubiquitin ligase and addresses its critical role in regulation of important biological processes. More importantly, its tremendous potential to be exploited for therapeutic purposes has been discussed.

The critical role of materials metrology in engineering

1987 ◽  
Vol 322 (1567) ◽  
pp. 361-372
Keyword(s):  
High Performance ◽  
Critical Role ◽  
Test Procedures ◽  
Engineering Structures ◽  
Codes Of Practice ◽  
Materials Research ◽  
Future Technologies ◽  
Industrial Needs ◽  
Industrial Standards

This paper analyses the critical underpinning role of materials research and testing for contemporary engineering and future technologies. It is obvious that measurements, tests and evaluations of materials and components, i.e. materials metrologies, are crucial to provide the information and data needed to optimize the function of engineering structures. The industrial needs and research trends in materials metrology are reviewed, and recent BAM-developments of measuring techniques for high-technology sectors, like high-temperature technology or high-performance ceramics, are presented. Finally, the relevance of an appropriate metrological base for the establishment of industrial standards, agreed codes of practice and the harmonization of test procedures for the international trade of technical products is discussed.

scholarly journals Role of Hydrogen Sulfide in the Pathology of Inflammation

Scientifica ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Madhav Bhatia
Keyword(s):  
Hydrogen Sulfide ◽  
Joint Inflammation ◽  
Chronic Obstructive ◽  
Therapeutic Approaches ◽  
Obstructive Pulmonary Disease ◽  
The Past ◽  
Inflammatory Conditions ◽  
Incurable Disease ◽  
Active Research

Hydrogen sulfide (H2S) is a well-known toxic gas that is synthesized in the human body from the amino acids cystathionine, homocysteine, and cysteine by the action of at least two distinct enzymes: cystathionine-γ-lyase and cystathionine-β-synthase. In the past few years, H2S has emerged as a novel and increasingly important biological mediator. Imbalances in H2S have also been shown to be associated with various disease conditions. However, defining the precise pathophysiology of H2S is proving to be a complex challenge. Recent research in our laboratory has shown H2S as a novel mediator of inflammation and work in several groups worldwide is currently focused on determining the role of H2S in inflammation. H2S has been implicated in different inflammatory conditions, such as acute pancreatitis, sepsis, joint inflammation, and chronic obstructive pulmonary disease (COPD). Active research on the role of H2S in inflammation will unravel the pathophysiology of its actions in inflammatory conditions and may help develop novel therapeutic approaches for several, as yet incurable, disease conditions.

scholarly journals Interfacial Acidity on Oxide Surfaces: A Scaling Paradigm and the Role of the Hydrogen Bond

2020 ◽  
Author(s):  
Robert Chapleski ◽  
Azhad U. Chowdhury ◽  
Kyle Mason ◽  
Robert Sacci ◽  
Benjamin Doughty ◽  
...  
Keyword(s):  
Density Functional ◽  
Critical Role ◽  
Surface Interactions ◽  
Van Der Waals Interactions ◽  
Chemical Transformations ◽  
Acid Base ◽  
Functional Theory ◽  
Fundamental Understanding ◽  
Molecule Surface

<p><a></a>A fundamental understanding of acidity at an interface, as mediated by structure and molecule-surface interactions, is essential to elucidate the mechanisms of a range of chemical transformations. While the strength­­­­ of an acid in the gas and solution phases is conceptually well understood, how acid-base chemistry works at an interface is notoriously more complicated. Using density functional theory and nonlinear vibrational spectroscopy, we have developed a method to determine the interfacial Brønsted-Lowry acidity of aliphatic alcohols adsorbed on the {100} surface of the model perovskite, strontium titanate. Here we show that, while shorter and less branched alkanols are less acidic as a gas and more acidic in solution, shorter alcohols are less acidic whereas less substituted alkanols are more acidic at the gas-surface interface. Hydrogen bonding plays a critical role in defining acidity, whereas structure-acidity relationships are dominated by van der Waals interactions between the alcohol and the surface.</p><p><a></a></p><p> </p>

scholarly journals Book Review: The Role of the Electronic Resources Librarian

2020 ◽  
Vol 64 (4) ◽  
pp. 186
Author(s):  
Jennifer Murray
Keyword(s):  
Academic Libraries ◽  
Electronic Materials ◽  
Organizational Structures ◽  
Online Environment ◽  
Electronic Resource ◽  
Skill Sets ◽  
The Past ◽  
Current Trends

The eight chapters covered in this text give a detailed history about how the role of electronic resource (e-resource) librarians (ERLs) has evolved over the past several decades as libraries have shifted to an online environment. It covers the challenges faced from 1992 when the ERL title was first used, to 2019 where academic libraries are still a hybrid of print and electronic materials. The book is organized into eight chapters with three appendixes. The introduction gives a brief overview on the development of ERLs and a clear synopsis of chapters, which are a nice progression of how the ERL position has developed since the 1990s; how it has been represented in organizational structures across academic libraries; how it has handled a variety of obstacles (technology, expanding skill sets, budget constraints, etc.); and how it maps to current trends in managing e-resources.

scholarly journals Therapeutic Effects of Melatonin on Ocular Diseases: Knowledge Map and Perspective

2021 ◽  
Vol 12 ◽  
Author(s):  
Haozhe Yu ◽  
Qicong Wang ◽  
Wenyu Wu ◽  
Weizhen Zeng ◽  
Yun Feng
Keyword(s):  
Clinical Evidence ◽  
Critical Role ◽  
Knowledge Map ◽  
Therapeutic Effects ◽  
Ocular Diseases ◽  
Ocular Tissues ◽  
The Past ◽  
Clinical Transformation ◽  
And Oxidative Stress

Melatonin plays a critical role in the pathophysiological process including circadian rhythm, apoptosis, and oxidative stress. It can be synthesized in ocular tissues, and its receptors are also found in the eye, triggering more investigations concentrated on the role of melatonin in the eye. In the past decades, the protective and therapeutic potentials of melatonin for ocular diseases have been widely revealed in animal models. Herein, we construct a knowledge map of melatonin in treating ocular diseases through bibliometric analysis and review its current understanding and clinical evidence. The overall field could be divided into twelve topics through keywords co-occurrence analysis, in which the glaucoma, myopia, and retinal diseases were of greatest research interests according to the keywords burst detection. The existing clinical trials of melatonin in ocular diseases mainly focused on the glaucoma, and more research should be promoted, especially for various diseases and drug administration. We also discuss its bioavailability and further research topics including developing melatonin sensors for personalized medication, acting as stem cell therapy assistant drug, and consuming food-derived melatonin for facilitating its clinical transformation.

Precision medicine: Driving the evolution of biobanking quality

2020 ◽  
Vol 33 (3) ◽  
pp. 102-106 ◽  
Author(s):  
Rebecca O. Barnes ◽  
Peter H. Watson
Keyword(s):  
Data Quality ◽  
Precision Medicine ◽  
Healthcare System ◽  
Biological Samples ◽  
Critical Role ◽  
Quality Requirements ◽  
The Past ◽  
The Impact ◽  
Research Domain

The promise of precision medicine will only be realized if the healthcare system adapts to meet some key infrastructure needs. Among these needs are adequate biobanking practices, capable of producing the biological samples and data that precision medicine relies upon in both the research and clinical phases. Within the research domain, there have been significant improvements to biobanking processes over the past two decades, driven by increased understanding of the impact of pre-analytical variability and the critical role of biospecimen and data quality. In the era of precision medicine, biobanking to support clinical needs has similar quality requirements. The extensive knowledge and resources that have been developed by the research biobanking community are available for adoption by clinical biobanking. The challenge and opportunity now presented to the healthcare system is to adopt or adapt these resources, for example, external biobanking standards and verification programs.

Performance Feedback Persistence: Comparative Effects of Historical Versus Peer Performance Feedback on Innovative Search

2020 ◽  
pp. 014920632091622 ◽  
Author(s):  
Yang Ye ◽  
Wei Yu ◽  
Robert Nason
Keyword(s):  
Performance Feedback ◽  
Critical Role ◽  
Theory Of The Firm ◽  
Theoretical Development ◽  
Panel Regression ◽  
The Past ◽  
Likelihood Analysis ◽  
Peer Performance ◽  
Quasi Maximum Likelihood

Firms use aspirations to regulate innovative search activities, but peer and historical referents may contain different signals regarding performance feedback. Integrating insights from the literature on profit persistence with the behavioral theory of the firm, we propose a persistence-based framework of organizational innovative search that connects the persistence characteristics of feedback from peer and historical referents with innovative search. We first predict that feedback from peer referents is more persistent than feedback from historical referents. Further, we theorize that peer performance feedback produces more pronounced effects: Performance above (below) peer aspiration leads to less (more) innovative search compared with performance above (below) the historical aspiration level. In addition, because industries impose heterogeneous levels of profit persistence, the differential effect between peer and historical performance feedback on innovative search is likely to be more evident in highly persistent industries. Examining the research-and-development intensity of a comprehensive panel of Compustat manufacturing firms over the past 45 years, our results from quasi–maximum likelihood analysis and fixed-effect panel regression largely support our theoretical development. Our study extends a nascent understanding of aspiration heterogeneity by revealing and empirically confirming the critical role of persistence.

The Critical Role of Microscopy and Spectroscopy in the Development of New Materials for Microelectronics Packaging

1996 ◽  
Vol 54 ◽  
pp. 634-635
Author(s):  
R.A. Youngman
Keyword(s):  
Thermal Conductivity ◽  
Critical Role ◽  
New Materials ◽  
Considerable Time ◽  
Microelectronics Packaging ◽  
Sintered Ceramic ◽  
The Past ◽  
Sintered Aluminum ◽  
New Material

It has been over thirty years since sintered aluminum nitride (AIN) has been the focus of many research and development activities in Japan, the U.S., and Europe. Only in the past 5 years has there been significant use of this material in microelectronics. There are many reasons for this considerable time for application including, technology needs and acceptance of a new material. Also important has been the role of materials understanding of AIN through the use of microscopy and spectroscopy. We illustrate the use of both standard and unique characterization techniques to elucidate the nature of the crystalline defects which control the important property of thermal conductivity.The thermal conductivity of pure AIN is 320 W/mK. This value has never been achieved in a sintered ceramic. In order to develop a sintered AIN with a high thermal conductivity it is necessary to understand the factors which control the thermal conductivity.

Sign in / Sign up

Export Citation Format

Share Document