Characterization of Dichlorosilane Based Tungsten Silicide Films For Local Interconnects

1996 ◽  
Vol 427 ◽  
Author(s):  
Cengiz S. Ozkan ◽  
Mansour Moinpour ◽  
Mehmet Sarikay
Keyword(s):  
Process Development ◽  
Ion Beam ◽  
Impurity Content ◽  
Processing Parameters ◽  
Cross Sectional ◽  
Tungsten Silicide ◽  
High Temperature Furnace ◽  
Wide Range ◽  
The Individual ◽  
Film Substrate

AbstractUltrathin refractory metal silicide films, such as tungsten silicide (WSix) offer a wide range of applications in VLSI and ULSI circuits such as local interconnects, bit lines and wordlines. One practical way of depositing WSix is by a CVD technique in which WF6 is reduced by either SiH4 or SiH2Cl2. For sub 0.5 micron technologies, SiH4 based WSix shows limitations due to poor step coverage and high F incorporation (>1020 atoms/cm3 ). If the reducing agent is changed to SiH2Cl2, then these problems are largely eliminated. However, interactions between processing parameters and film properties to achieve compositionally and structurally uniform films are not well understood. In this investigation, SiH2Cl2 based WSix films (60-200 nm) deposited on undoped poly-Si, doped poly-Si and oxide substrates were studied after a high temperature furnace anneal and oxidation cycle. Electron transparent samples were prepared by a low temperature ion beam technique and the individual films of Si-SiO2-poly Si-WxSiy layers were investigated by high resolution cross sectional transmission electron microscopy, x-ray diffraction and electron nanospectroscopy techniques with a beam energy of 300 kV. RBS measurements were used to determine the composition profile through the depth of the film and Si/W uniformity in terms of Si-rich and W-rich interfaces. SIMS measurements were used to determine the impurity content in the silicide film and at the film/substrate interface. This paper focuses on the processing-structure relationships in terms of development of defect structures within WxSiy, the non-stoichiometric W-Si compositons and related crystal structures and the role of the nucleation step in modulating the Si/W ratio at the WSix, /poly-Si interface and discusses their implications on future process development.

Effect of Substrate Temperature on Properties of Nano-Scale Functionally Graded Calcium Phosphate Coatings

2006 ◽  
Author(s):  
Travis Blalock ◽  
Xiao Bai ◽  
Afsaneh Rabiei
Keyword(s):  
Electron Microscopy ◽  
Calcium Phosphate ◽  
Substrate Temperature ◽  
Ion Beam ◽  
Processing Parameters ◽  
Functionally Graded ◽  
Cross Sectional ◽  
X Ray ◽  
Phosphate Coatings ◽  
Calcium Phosphate Coatings

The effect of substrate temperature and processing parameters on microstructure and crystallinity of calcium phosphate coatings deposited on heated substrates in an Ion Beam Assisted Deposition (IBAD) system are being studied. The experimental procedures include mechanical testing and film thickness measurements using bonding strength and profilometery. Cross-sectional scanning transmission electron microscopy (STEM) with energy dispersive X-ray spectroscopy (EDX) through the thickness of the film as well as scanning electron microscopy (SEM) with EDX at the top surface of the film was performed to evaluate the microstructure of the film. The coating crystallinity was studied through X-ray diffraction (XRD). The information gained from current analysis on the set temperature coatings will be used to refine the processing techniques of the Functionally Graded Hydroxyapatite (FGHA) coating.

scholarly journals Disentangling the Main Components of Hydromorphological Modifications at Reach Scale in Rivers of Greece

Hydrology ◽  
2020 ◽  
Vol 7 (2) ◽  
pp. 22
Author(s):  
Konstantinos Stefanidis ◽  
Anna Latsiou ◽  
Theodora Kouvarda ◽  
Anastasia Lampou ◽  
Nektarios Kalaitzakis ◽  
...  
Keyword(s):  
Habitat Modification ◽  
Ecological Quality ◽  
Cross Sectional ◽  
Habitat Features ◽  
Wide Range ◽  
Cross Sectional Profile ◽  
Sectional Profile ◽  
Main Components ◽  
The Individual ◽  
River Habitat Survey

The Water Framework Directive (WFD) requires from member states to monitor hydromorphological features of rivers in order to assess their ecological quality. Thus, numerous hydromorphological assessment methods have been developed with most of them focusing on the dynamics of hydrology, geomorphology and riparian zone extent. Within the scope of this study, we assessed the hydromorphological features of 106 river reaches distributed among thirteen WFD River Basin Districts (RBDs) to identify the main drivers of hydromorphological perturbation at a national scale. The studied reaches reflect a wide range of natural variability as they include various types of watercourses extending from lowlands to mid-altitude and mountainous systems. We employed the River Habitat Survey (RHS), and we recorded hydromorphological features and modifications in both banks and the channel bed along 500 m for each reach. Then, the Habitat Modification Score (HMS) and the individual sub-scores that indicate the extent of specific modifications (e.g., bridges, fords, weirs, bank reprofiling, bank reinforcement, etc.) were calculated in order to a) assess the severity of the total artificial modification and b) to highlight the most common and severe causes of overall alteration. The results showed that alterations such as reprofiling and reinforcement of banks contributed the most to the total HMS followed by the presence of fords and bridges. Particularly, the bank alterations indicate a serious deterioration of the longitudinal profile of the reaches, while the occurrence of many fords and bridges is the main cause for perturbations that affect locally the stream cross-sectional profile. Overall, these results compile a first nationwide assessment of the hydromorphological status of Greek rivers in line with the WFD and set the basis for further research that will focus on the diversity of stream habitat features as a measure for the overall ecological quality.

Discharge Jet Interaction With Multiple Port Diffusers

1982 ◽  
Vol 104 (1) ◽  
pp. 40-45 ◽  
Author(s):  
F. Y. Sorrell ◽  
B. W. Smith
Keyword(s):  
Near Field ◽  
Flow Dynamics ◽  
Cross Sectional ◽  
Jet Interaction ◽  
Round Jets ◽  
Marine Outfall ◽  
Wide Range ◽  
Flow Similarity ◽  
The Individual ◽  
Over The Top

A model for the flow dynamics and mixing in the near-field of a multiple port outfall diffuser is postulated. It employs the equations for gross conservation of mass, momentum, and buoyancy of the fluid in the discharge jet or plume. These equations are obtained by assuming flow similarity and then integrating over the cross-sectional area of the plume. Two distinct interactions of the discharge jets or plumes are included in the model. These are the interaction of the individual round jets from the diffuser ports and the merging of the plume from either side of the diffuser, over the top of the diffuser. The resulting equations are closed by the “entrainment assumption” and solved numerically. Results provide the velocity, width, and dilution of the jet or plume. Calculations were made for a number of cases where experimental results were available. The model gives reasonable agreement with the experiments over a wide range of discharge conditions and over the complete range of flow patterns. In most cases it slightly underestimates the mixing or dilution. Therefore the model should be useful in determining the minimum dilution that can be expected from any marine outfall.

Ion Beam Mixing of High-Tc Superconductor Components.

1988 ◽  
Vol 128 ◽  
Author(s):  
P. Borgesen ◽  
D. A. Lilienfeld
Keyword(s):  
Ion Beam ◽  
Superconducting Thin Films ◽  
Ion Beam Mixing ◽  
High Tc ◽  
Fundamental Interest ◽  
High Tc Superconductor ◽  
Wide Range ◽  
Mixing Rates ◽  
The Individual ◽  
Binary Mixing

ABSTRACTThe design of the necessary multilayer structures for producing superconducting thin films by ion beam mixing methods requires, among others, the knowledge of the individual (binary) mixing rates. In order to measure these, various combinations of Y, Ba, Cu, and Bi were irradiated with 600 keV Xe-ions at 80K and 300K. The systems exhibited a wide range of mixing behaviors which are also of fundamental interest. Ba and Cu readily formed the BaCu phase, and further mixing with Cu progressed only via binary collision mechanisms. At 80K Cu and Y were rapidly mixed in any ratio by thermal spikes, whereas a Cu rich sample rapidly formed the Cu6Y phase at 300K. Ba could not be mixed into Y or a Y-Cu mixture. Finally, irradiation of polycrystalline layers of Cu and Bi apparently lead to rapid motion of Bi along grainboundaries at both temperatures.

scholarly journals Co-infections by non-interacting pathogens are not independent & require new tests of interaction

2019 ◽  
Author(s):  
Frédéric M. Hamelin ◽  
Linda J.S. Allen ◽  
Vrushali A. Bokil ◽  
Louis J. Gross ◽  
Frank M. Hilker ◽  
...  
Keyword(s):  
Survey Data ◽  
Epidemic Models ◽  
Statistical Independence ◽  
Epidemiological Models ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Underlying Assumption ◽  
Positive Correlation ◽  
Wide Range ◽  
The Individual

AbstractIf pathogen species, strains or clones do not interact, intuition suggests the proportion of co-infected hosts should be the product of the individual prevalences. Independence consequently underpins the wide range of methods for detecting pathogen interactions from cross-sectional survey data. However, the very simplest of epidemiological models challenge the underlying assumption of statistical independence. Even if pathogens do not interact, death of co-infected hosts causes net prevalences of individual pathogens to decrease simultaneously. The induced positive correlation between prevalences means the proportion of co-infected hosts is expected to be higher than multiplication would suggest. By modeling the dynamics of multiple non-interacting pathogens, we develop a pair of novel tests of interaction that properly account for non-independence. Our tests allow us to reinterpret data from previous studies including pathogens of humans, plants, and animals. Our work demonstrates how methods to identify interactions between pathogens can be updated using simple epidemic models.

Ion Beam Synthesis of IrSi3 by 1-MeV Ir Ion Implantation into Si(111)

1993 ◽  
Vol 320 ◽  
Author(s):  
T. P. Sjoreen ◽  
H.- J. Hinneberg
Keyword(s):  
Ion Implantation ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Processing Parameters ◽  
Cross Sectional ◽  
Ion Channeling ◽  
Transmission Electron ◽  
Nearly Continuous ◽  
Substrate Temperatures ◽  
Different Doses

ABSTRACTThe formation of a Si/IrSi3/Si heterostructurie by 1-MeV Ir ion implantation and subsequent annealing has been studied for different doses (0.1-2.25 × 1017 Ir/cm2), substrate temperatures (450°-600°C) and annealing temperatures (1000°-1200°C) using Rutherford backscattering spectrometry, ion channeling and cross-sectional transmission electron microscopy. The heterostructure formation is observed to depend strongly on the processing conditions. The best structure, nearly continuous and precipitate-free, is obtained by implanting 1.8-2.0× 1017 1r/cm2 at a substrate temperature of 550°C and annealing at 1100°C for 5 h. A stoichiometric IrSi3 layer can also be produced by furnace annealing at 1150°C for 1 h or by rapid-thermal-annealing at 1200°C for 3 min. Other substrate temperatures generally lead to a structure with a discontinuous IrSi3 layer frequently interrupted by large surface precipitates or islands. The origin of these islands, as well as the dependence of the heterostructure on processing parameters, is discussed.

Ion Beam Synthesis of IrSi3 by 1-MeV Ir Ion Implantation into Si(111)

1993 ◽  
Vol 316 ◽  
Author(s):  
T. P. Sjoreen ◽  
H.-J. Hinneberg
Keyword(s):  
Ion Implantation ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Processing Parameters ◽  
Cross Sectional ◽  
Ion Channeling ◽  
Transmission Electron ◽  
Nearly Continuous ◽  
Substrate Temperatures ◽  
Different Doses

ABSTRACTThe formation of a Si/IrSi3/Si heterostructure by 1-MeV Ir ion implantation and subsequent annealing has been studied for different doses (0.1-2.25 × 1017 Ir/cm2), substrate temperatures (450°-600°C) and annealing temperatures (1000°-1200°C) using Rutherford backscattering spectrometry, ion channeling and cross-sectional transmission electron microscopy. The heterostructure formation is observed to depend strongly on the processing conditions. The best structure, nearly continuous and precipitate-free, is obtained by implanting 1.8-2.0 × 1017 Ir/cm2 at a substrate temperature of 550°C and annealing at 1100°C for 5 h. A stoichiometric IrSi3 layer can also be produced by furnace annealing at 1150°C for 1 h or by rapid-thermal-annealing at 1200°C for 3 min. Other substrate temperatures generally lead to a structure with a discontinuous IrSi3 layer frequently interrupted by large surface precipitates or islands. The origin of these islands, as well as the dependence of the heterostructure on processing parameters, is discussed.

Doppelphotonen-Absorptiometrie: Eine neue Methode zur Bestimmung des Knochenmineralgehaltes. I. Grundlagen

1988 ◽  
Vol 27 (01) ◽  
pp. 12-18 ◽  
Author(s):  
J. Eiber ◽  
J. Hennig ◽  
H W. Pabst ◽  
G. Buttermann
Keyword(s):  
Fracture Risk ◽  
Early Stage ◽  
Low Cost ◽  
Premenopausal Women ◽  
Bone Diseases ◽  
Dual Photon Absorptiometry ◽  
Neck Of Femur ◽  
Cross Sectional ◽  
Wide Range ◽  
The Individual

Today dual-photon absorptiometry (DPA) is recommended as the best procedure for diagnosing osteoporosis at an early stage considering its low cost, low radiation exposure and reasonable reliability. Cortical (neck of femur) and trabecular (L 2-4) bone mass has been determined repeatedly with DPA using 153Gd (NOVO Lab 22 a) in 545 females and 112 males with no evidence of bone diseases. Measured “normal” (age-and sex-related average) values for bone mineral content (BMC) differed significantly (p <0.01) from those of US inhabitants determined by the same equipment, i. e., they were on average about 30% lower, but matched well with corresponding results from Belgium. BMC-area was found the most suitable parameter both for cross-sectional and longitudinal studies, since it is independent of height and weight. But there is still need to reduce the overlap and improve accuracy and reproducibility for making decisions after shorter intervals. - Assessment of the individual mineral loss and fracture risk by comparison with average values remains problematical due to the wide range of “normal” BMC values, and in women additionally due to the variable onset of menopause. For estimations of the individual fracture risk of elderly patients BMC should not be normalized on age, because at the age of 65 half of the women had “pathologic” values, i.e. were below the so-called “osteoporosis threshold”. Comparison of the individually measured postmenopausal BMC with average values of premenopausal women and with BMC values normalized to their menopausal age may be helpful approaches to overcoming these difficulties. Because of the lack of earlier individual data in most cases repeated BMC measurements are still required for assessment of demineralization speed.

The Effect of Implanted Gallium on the Recrystallization of Amorphous Layers formed during FIB Milling of Silicon

2001 ◽  
Vol 7 (S2) ◽  
pp. 958-959
Author(s):  
S. Rubanov ◽  
P.R. Munroe
Keyword(s):  
Focused Ion Beam ◽  
Ion Beam ◽  
Amorphous Layer ◽  
High Energy ◽  
Specimen Preparation ◽  
Silicon Sample ◽  
Cross Sectional ◽  
Wide Range ◽  
Average Size ◽  
Beam Currents

The focused ion beam (FIB) miller allows preparation of site-specific transmission electron microscopy (TEM) specimens from a wide range of materials in both cross-sectional and planar configurations [1,2]. However, radiation damage during exposure to the high-energy gallium beam may result in the formation of amorphous regions on thin film specimens. The thickness of such damage layers, on both sides of a TEM specimen, is comparable with the thickness required for lattice imaging. For example, the thickness of an amorphous layer in Si after 30 kV Ga+ FIB processing has been reported in the range from 15 [3] to 28 nm [4]. This problem limits the capabilities of FIB sample fabrication.The aim of this study was to investigate, in detail, the structure, composition and the thickness of the damage layers in Si specimens after milling with a gallium ion beam. Using a FEI xP200 FIB system, with 30 kV Ga+ ions, a row of trenches on a silicon sample was milled under different beam currents ranging from 150 to 6600 pA. The average size of such trenches was 15×10 μm wide and 1 μm deep. The trenches were then removed from the FIB and sputter coated with a thick Au film to preserve the trench surfaces from further damage during subsequent TEM specimen preparation steps. Cross-sectional TEM specimens of the trench walls were then prepared using standard FIB procedures [5]. Observations were made using a Philips CM 200 Field Emission Gun TEM operating at an accelerating voltage of 200 kV.

Controllable Synthesis of Different Bismuth Ferrites by a PVA Modified Hydrothermal Method and Photocatalytic Characterization

2013 ◽  
Vol 1552 ◽  
pp. 35-41 ◽  
Author(s):  
Tong Tong ◽  
Dengren Jin ◽  
Jinrong Cheng
Keyword(s):  
Hydrothermal Method ◽  
Phase Evolution ◽  
Xrd Analysis ◽  
Processing Parameters ◽  
X Ray Diffraction ◽  
Light Region ◽  
Wide Range ◽  
The Individual ◽  
Degradation Effect ◽  
Modified Hydrothermal Method

ABSTRACTBismuth ferrites crystallites were synthesized by a polyvinyl alcohol (PVA) modified hydrothermal method. X-ray diffraction (XRD) analysis indicated that the pure phase of Bi25FeO40, BiFeO3 and Bi2Fe4O9 were synthesized with initial Bi/Fe ratio of 1:1 at the temperature of 200°C for 24 h, using NaOH concentration of 2, 5 and 10 M, respectively. With addition of PVA, the individual Bi-Fe oxides could be existed in a more wide range of processing parameters. The phase evolution of bismuth ferrites in the process of hydrothermal reactions was discussed. Moreover, photocatalytic properties of the bismuth ferrites crystallites were explored. The results showed that they possessed band gaps of about 2.0 eV and performed good degradation effect at visible light region.

Sign in / Sign up

Export Citation Format

Share Document