bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study for plasma etching of dielectric film in semiconductor device manufacturing. Review of ASET research project
Authors: Sekine Makoto 
Published: October 2007

Abstract
Conventional developments were conducted in a very empirical way, such as a trial and error with many speculations using qualitative data. This approach requires more and more resources and time for the development of future devices with a design rule below 100 nm in the system on a chip (SOC) era. It is necessary to establish a systematic methodology for process development and qualification. ASET Plasma Laboratory had been found to research a basis for the systematic development of the plasma etching technology. Fluorocarbon (CF) plasma for the etching of high-aspect-ratio contact holes in SiO2 was investigated intensively in the 5-year program that finished in March 2001. They introduced 5 plasma sources that can etch 0.1-mm contact holes on a 200-mm wafer in production, and state-of-the-art diagnostics tools for the plasma and etched surface. The SiO2 etch mechanism was revealed from the etch species generation to the reaction in a deep hole. The number of electron collisions to fluorocarbon gas molecule is proposed as an important parameter to control the gas dissociation and etch species flux to the surface. An etch reaction model was also proposed using the estimated-surface-reaction probability that is a function of ion energy and CF polymer thickness that reduces the net ion energy to the reaction layer. The CF polymer thickness was determined by a balance equation of generation term (radical fluxes) and loss terms (etching by ions, radicals, and out-flux oxygen from SiO2). A program was developed and successfully predicts the etch rates of Si-containing materials, including organic dielectrics. Requirements for the next-generation plasma etch tools are also discussed.
Diagnostics of etching plasmas
Authors: Booth Jean-Paul 
Published: October 2007

Abstract
Radio-frequency excited, low-pressure plasmas in halogen-containing gases are widely used to etch submicronic features in a range of materials during integrated circuit manufacture. Costly process-drift problems are often caused by the ubiquitous deposition of polymer layers on the reactor walls. Simple and robust sensors of the reactor performance are needed to monitor and manage these effects. This paper presents results obtained in industrial plasma-etching machines using a deposition-tolerant ion flux probe and broadband UV­vis absorption spectroscopy.
Role of ions in SiO2 deposition with pulsed and continuous helicon plasmas
Authors: Charles Christine 
Published: October 2007

Abstract
Good-quality silicon dioxide films have been deposited at low temperature (200 °C) using continuous and pulsed oxygen/silane plasmas coupled in a high-density, low-pressure helicon reactor. Although the total ion flux determines many of the structural properties of the deposited oxide, we have found that silicon-containing ions contribute to the film growth (up to 50 %) and appear to be responsible for the measured compressive stress.
Plasma-assisted production of hydrogen from hydrocarbons
Authors: Deminsky Maxim , Jivotov Victor , Potapkin Boris , Rusanov Vladimir 
Published: October 2007

Abstract
This paper is dedicated to the discussion of possible plasma applications for hydrogen-rich gas production from hydrocarbons. Different types of plasma, both thermal and nonequilibrium ones, are under consideration. A special attention is devoted to experimental and theoretical results on hydrocarbon conversion in nonequilibrium plasma of pulse microwave discharge. A comparison of plasma methods and conventional catalytic technology is presented as well.
Generation of thermal plasmas in liquid-stabilized and hybrid dc-arc torches
Authors: Hrabovský Milan 
Published: October 2007

Abstract
The paper presents survey of principles and basic physical parameters of liquid and hybrid gas/liquid dc-arc plasma torches and discusses physical mechanisms that control plasma properties. Special attention is devoted to properties of generated plasma that are decisive for performance characteristics in plasma spraying. Characteristics of water and water-argon torches are compared with typical characteristics of commonly used gas torches.
Nonthermal and nonequilibrium effects in high-power pulsed ICP and application to surface modification of materials
Authors: Ishigaki T. , Okada N. , Ohashi N. , Haneda H. , Sakuta T. 
Published: October 2007

Abstract
Newly developed pulse-modulated high-power inductively coupled plasma (ICP) is expected to offer the unique physicochemical condition, such as the increased concentration of chemically reactive species, as well as the appropriate heat flux for materials processing. Two kinds of oxide materials, titanium and zinc oxide, were placed at the downstream of Ar­H2 ICP and irradiated in the plasma of continuous (CN) and pulse-modulated (PM) modes. The CN-ICP irradiation at the position close to the plasma tail gave rise to the thermal reduction of oxides. In the PM-ICP irradiation, the degree of thermal reduction depended on the lower power level during pulse-off time, as well as the total electric power. Irradiation in PM-ICP led to the increased formation of oxygen vacancies in titanium dioxide. In the case of zinc oxide, the UV emission efficiency was improved by PM-ICP irradiation, while the green emission became predominant by CN-ICP irradiation at the appropriate position. Induced effects in the two oxides by PM-ICP would be related to the high concentration of hydrogen radicals in the plasma.
Ultrashort pulsed barrier discharges and applications
Authors: Okazaki Ken , Nozaki Tomohiro 
Published: October 2007

Abstract
Atmospheric pressure nonequilibrium plasmas have made a recent remarkable progress in formation techniques including atmospheric pressure glow discharge (APG), dielectric barrier discharge (DBD), corona discharge, surface discharge, ultrashort pulsed discharge, etc., and are expanding their applications into the field of energy and environment as well as material conversion processes. This paper will especially focus on a large improvement of DBD by combining it with squared ultrashort high voltage pulses and various applications.
"Simple" diagnostics for characterization of low-pressure chemically active plasmas
Authors: Otorbaev D. K. 
Published: October 2007

Abstract
In the current paper, the "simple" diagnostics for characterization of nonequilibrium chemically active plasmas are discussed. As to experimental methods, "simple" noninvasive spectroscopic methods of ionizing and recombining plasma characterization have been emphasized. The word "simple" in the title is presented in quotes, which means that the methods are assumed to be simple only conditionally. In order to be sure that the measurements indeed provide correct information on the plasma parameters, a detailed understanding of kinetics of each particular plasma source is required. Moreover, the validity of spectroscopic methods should be checked by independent diagnostic techniques.
Excilamps as efficient UV­VUV light sources
Authors: Tarasenko Victor F. 
Published: October 2007

Abstract
Operating parameters of powerful UV and vacuum ultraviolet (VUV) excilamps with different discharge geometry excited by capacitive discharge, barrier discharge, glow discharge, and UV-preionized discharge were investigated. Intense radiation of Ar2*, Kr2*, Xe2*, ArF*, KrBr*, KrCl*, KrF*, XeI*, Cl2, XeBr*, XeCl*, XeF* molecules and I* atoms was obtained in rare gas or in rare gas­F2 (Br2, CH3Br, Cl2, Br2, HCl, I2, NF3) mixtures.
Superhard nanocomposite coatings. From basic science toward industrialization
Authors: Veprek S. , Jilek M. 
Published: October 2007

Abstract
A variety of superhard coatings with Vickers plastic hardness exceeding 40 GPa have been reported by several research groups during the last five years (for recent reviews see refs [1,2]). However, one has to distinguish between superhard nanocomposites, such as nc-TiN/a-Si3N4, nc-TiN/a-Si3N4/a- and nc-TiSi2, nc-(Ti1-xAlx)N/a-Si3N4, nc-TiN/TiB2, nc-TiN/BN, etc. where the high hardness originates from the nanostrucutre and, therefore, remains stable upon annealing to high temperatures [1], and coatings, such as CrN/Ni, ZrN/Ni, and others [2] in which the measured high hardness is due to a high compressive stress that is induced in the coatings due to energetic ion bombardment during their deposition (e.g., by magnetron sputtering). We also summarize the recent progress in the industrial applications of the superhard nanocomposite coatings on machining tools.
Clustering phenomena in low-pressure reactive plasmas. Basis and applications
Authors: Watanabe Y. , Shiratani M. , Koga K. 
Published: October 2007

Abstract
Clustering phenomena of particles below a few nm in size in low-pressure reactive plasmas have been studied in capacitively coupled high-frequency SiH4 discharges. Clusters nucleate around a size of 0.5 nm, Si4Hx and subsequently grow due to influxes of SinHx (1 < n < 4) and other molecular species. Because of long gas-residence time and small surface loss-probability of clusters, even neutral ones accumulate to nucleate in the reactor. Appearance of negatively charged clusters is considered to become noticeable at around Si4Hx. The growth of clusters is suppressed by using thermophoretic force, gas flow, periodical discharge modulation, and hydrogen dilution. The reactor has been newly developed to suppress the growth of clusters both by thermophoretic force and by gas flow and evacuation without stagnation. Using the reactor, a-Si:H films of extremely high quality have been successfully deposited.
How to exploit ion-induced stress relaxation to grow thick c-BN films
Authors: Ziemann P. , Boyen H.-G. , Deyneka N. , Widmayer P. , Banhart F. 
Published: October 2007

Abstract
A recently developed procedure is reviewed allowing thick (>1 mm), high-quality c-BN films (>80 % c-BN) to be grown. It is based on the observation that compressive stress inevitably present in such films can be released by medium-energy (some hundred keV) ion irradiation without destroying the cubic phase.
Definitions of basic terms relating to polymer liquid crystals (IUPAC Recommendations 2001)
Authors: Barón Máximo , Stepto R. F. T. 
Published: October 2007

Abstract
The document first gives definitions of basic terms related to liquid-crystalline and mesomorphic states of matter and then terms specific to the classification of liquid-crystal polymers. The terms have been restricted to those most commonly encountered in the structural description of the latter class of materials.
The terms have been selected from the recently published comprehensive document "Definitions of basic terms relating to low-molar-mass and polymer liquid crystals" [Pure and Applied Chemistry
73(5), 845-895 (2001)] and are intended to form a readily usable guide for the reader interested in the structural description of polymer liquid crystals. The more comprehensive document should be used for terminology associated with types of mesophases and the optical and physical characteristics of liquid-crystalline materials.
The advice given by representatives of the International Liquid Crystal Society for the preparation of this document is gratefully acknowledged.
Biodiversity: A wonderful source of exciting new pharmacophores. Further to a new theory of memory
Authors: Atta-ur-Rahman  , Choudhary M. Iqbal 
Published: October 2007

Abstract
The diverse biological resources in nature are vast factories of chemical diversity. With the recent advances in the biological and chemical sciences it is now easier than ever to explore the potential uses of immense biological resources in a sustainable manner. Our investigations focused on the bioprospecting of both terrestrial and marine organisms have led to the discovery of a number of interesting chemical compounds. The discovery of a new class of cholinesterase, α-glucosidase and phosphodiesterase I inhibitors, several new antioxidants, and other classes of bioactive natural products is presented. The theory of the chemical basis of memory through hydrogen bonding in the brain is further elaborated.
Australian biodiversity via its plants and marine organisms. A high-throughput screening approach to drug discovery
Authors: Quinn Ronald J. , de Almeida Leone Priscila , Guymer Gordon , Hooper John N. A. 
Published: October 2007

Abstract
High-throughput screening (HTS) of extracts of Australian plants and marine organisms commenced in our laboratory in 1994. The biota collections commenced in late 1993. The collection has in excess of 30 000 biota samples including over 16 000 biota samples of vascular plants, algae, and macro fungi from Queensland, and over 4000 marine invertebrates from Australian waters. The plant collection represents ∼9 % of the world species diversity of higher plants, with representation from 73 % of the world's plant families. The marine collection contains ∼10 % of the world diversity of sponges, ∼10 % of the world diversity of ascidians, and ∼5 % of the world diversity of soft corals and gorgonians.
The lecture will highlight some of the advances to knowledge about Australian biodiversity as a result of the HTS project, discuss drug discovery using HTS, and give some examples of the chemistry arising from the screening of the extracts.
Aromatic biodiversity among the flowering plant taxa of Turkey
Authors: Baser K. Hüsnü Can 
Published: October 2007

Abstract
Flora of Turkey is rich and diverse with well over 11 000 flowering taxa recorded in the 9-volume set of Prof. Davis's monumental work and its two supplements. Chemical diversity among the flowering plants of Turkey is well documented in the recently published volume 11 of the Flora of Turkey and the East Aegean Islands.
Among the aromatic taxa, remarkable examples can be found in families such as Labiatae, Compositae, Umbelliferae, etc. The occurrence of volatile chemicals in aromatic plants is not only an indication of chemical diversity but may also help solve taxonomical problems is comprehensively studied genera. Aromatic diversity is illustrated with examples from genera such as Sideritis, Salvia, Thymus, Origanum, Satureja, Thymbra, Mentha, Micromeria, Ziziphora, Calamintha, Cyclotrichium, Acinos, Echinophora, Ferulago, Heracleum, Pimpinella, Tanacetum, and Betula.
The economic implications of aromatic biodiversity and the importance of bioprospecting are highlighted.
Diversity of bulbous monocots in Turkey with special reference. Chromosome numbers
Authors: Özhatay Neriman 
Published: October 2007

Abstract
Turkey is among the richest countries in the world in terms of plant diversity. The aim of this paper is to show diversity of the petaloid and bulbous plants, which belong to monocotyledones. According to Flora of Turkey and its supplements, the number of species of bulbous monocotyledones is around 688, of which 244 are endemic (endemism 35.4 %). According to the statistical data of Turkish flowering plants based on the published records, only 15 % of the flora have information about chromosome counts, although bulbous monocots percentage is higher at 58 %. Fritillaria and Tulipa are stable genera as regards chromosome numbers with 2n = 24 and karyotype; on the other hand, the most variable genera are Crocus (2n = 6, 8, 10, 12, 14, 16, 18, 20, 22, 26, 28, 30, 70) and Ornithogalum (2n = 12, 14, 16, 18, 20, 21, 24, 27, 28, 32, 40, 45, 54, 60, 80).
Biodiversity in the alkaloids of Turkish Papaver species
Authors: Sariyar Günay 
Published: October 2007

Abstract
There are about 35 Papaver species growing in Turkey, which are grouped into eight sections, namely Argemonidium, Carinata, Glauca, Miltantha, Oxytona, Papaver, Pilosa, and Rhoeadium.
As a result of our extensive work on the alkaloids of Turkish Papaver species the presence of several chemotypes has been shown. Among these chemotypes, medicinally important alkaloids such as noscapine (=narcotine), papaverine- and thebaine-containing samples have been found as new sources for the production of them.
The infraspecific variation encountered within the Papaver species has been demonstrated mainly in two sections of the genus, Miltantha and Oxytona. The alkaloids of seven species (Papaver armeniacum, P. curviscapum, P. cylindricum, P. fugax, P. persicum, P. polychaetum, and P. triniifolium) of the section Miltantha have been studied, and the existence of chemical strains has been shown mainly in P. fugax, P. persicum, and P. triniifolium.
Investigations on the species of the section Oxytona indicated that there is a relationship between the major alkaloid content and the chromosome numbers of the samples.
Isolation of new secoberbine-type alkaloids as well as promorphinane- and morphinane-types has revealed the biosynthetic relationship between the alkaloids of Miltantha and Oxytona species. Chemical races are also known for species of Papaver within other sections of the genus.
P. lateritium of Turkish origin from section Pilosa yielded some secoberbine and protoberberine types, whereas P. rhopalothece of the section Rhoeadium contained narcotine as a major alkaloid. Isolation of spirobenzylisoquinoline type from P. argemone (sect. Argemonidium) was the first report of the occurrence of this type in the Papaveraceae.
Sulfate-sensing electrodes. The lead- amalgam/lead-sulfate electrode (IUPAC Technical Report)
Authors: Mussini Patrizia R. , Mussini Torquato 
Published: October 2007

Abstract
A new, simplified design and a convenient preparation procedure for the Pb(Hg)|PbSO4|SO4
2- electrode are proposed. This procedure ensures preparation of stable amalgams and reproducible electrode potentials, which make this electrode useful and attractive for both thermodynamic investigations and electroanalytical applications. For these purposes, the electrode prepared according to the proposed procedure has been exhaustively characterized both thermodynamically and as a sulfate-sensing electrode, in different sulfate solutions, including H2SO4. Also, a practical standardization procedure has been proposed. The Pb(Hg)|PbSO4|SO4
2- electrode can be structured with a built-in concentrated Li2SO4 salt bridge for use as a sulfate-based reference electrode. This electrode can be operated as a reference electrode alternative to the conventional calomel or Ag|AgCl reference electrodes in electroanalytical practice.
Molecular basis of biodiversity, conservation, and sustained innovative utilization (IUPAC Technical Report)
Authors: Fischli Albert E. , Pandit U. K. , Black David StC. 
Published: October 2007

Abstract
In this Technical Report, recommendations are presented for international cooperation between academia and industry on molecular biodiversity. The recommendations are based on discussions in workshops/meetings held in Amsterdam (The Netherlands), Belo Horizonte (Brazil), Bangkok (Thailand), Kunming (China), and Antalya (Turkey) involving national and international representatives of relevant organizations.
Medicinal chemistry in the new millennium. A glance into the future
Authors: Erhardt Paul W. 
Published: October 2007

Abstract
The future of medicinal chemistry as both a pure and an applied science has been considered relative to trends that are already having a significant impact upon drug discovery and development. After quickly reviewing how medicinal chemistry has been practiced to date, topics considered into the future include: pursuing therapeutic efficacy, addressing 3D structure within database settings, assuring absorption, directing distribution, controlling metabolism, optimizing elimination, and avoiding toxicity. It is suggested that as the exploration of these topics proceeds into the new millennium by deploying combinatorial chemistry coupled to high-throughput screening, medicinal chemistry will play a key role as a central interpreter of the underlying structure­activity relationships such that the overall process of drug discovery and development will be knowledge-generating. As fundamental knowledge accumulates across all of these areas, virtual approaches will eventually become firmly anchored to experimental and theoretical databases having validated clinical predictability. The potential impact of some of the recent trends in process chemistry, and in analytical chemistry using X-ray diffraction as an exemplary method, are additionally highlighted before reiterating the article's major points in a summary section. From this purview, the summary also considers the education of future medicinal chemists, notes potential issues related to the future of pharmaceutical-related intellectual property, and concludes by alluding to a brewing paradox between enhanced knowledge and enhanced molecular diversity relative to the future discovery of new drugs.
Naming of new elements(IUPAC Recommendations 2002)
Authors: Koppenol W. H. 
Published: October 2007

Abstract
A procedure is proposed to name new elements. After the discovery of a new element is established by a joint IUPAC­IUPAP Working Group, the discoverers are invited to propose a name and a symbol to the IUPAC Inorganic Chemistry Division. Elements can be named after a mythological concept, a mineral, a place or country, a property, or a scientist. After examination and acceptance by the Inorganic Chemistry Division, the proposal follows the accepted IUPAC procedure and is then submitted to the IUPAC Council for approval.
"Heavy metals" a meaningless term? (IUPAC Technical Report)
Authors: Duffus John H. 
Published: October 2007

Abstract
Over the past two decades, the term "heavy metals" has been widely used. It is often used as a group name for metals and semimetals (metalloids) that have been associated with contamination and potential toxicity or ecotoxicity. At the same time, legal regulations often specify a list of "heavy metals" to which they apply. Such lists differ from one set of regulations to another and the term is sometimes used without even specifying which "heavy metals" are covered. However, there is no authoritative definition to be found in the relevant literature. There is a tendency, unsupported by the facts, to assume that all so-called "heavy metals" and their compounds have highly toxic or ecotoxic properties. This has no basis in chemical or toxicological data. Thus, the term "heavy metals" is both meaningless and misleading. Even the term "metal" is commonly misused in both toxicological literature and in legislation to mean the pure metal and all the chemical species in which it may exist. This usage implies that the pure metal and all its compounds have the same physicochemical, biological, and toxicological properties, which is untrue. In order to avoid the use of the term "heavy metal", a new classification based on the periodic table is needed. Such a classification should reflect our understanding of the chemical basis of toxicity and allow toxic effects to be predicted.
Phane nomenclature. Part II. Modification of the degree of hydrogenation and substitution derivatives of phane parent hydrides (IUPAC Recommendations 2002)
Authors: Favre H. A. , Hellwinkel D. , Powell W. H. , Smith H. A. , Tsay S. S.-C. 
Published: October 2007

Abstract
Cyclophane and linear phane systems are considered as parent hydrides. Their derivatives are named in conformity with the principles, rules, and conventions prescribed for naming organic compounds. The following nomenclatural features are described: indicated and added hydrogen, order of seniority for numbering, substituents expressed as suffixes, substituents cited as prefixes, phane parent hydrides modified by addition or subtraction of hydrogen atoms, and polyfunctional derivatives.