High Bath Research Articles

Electrodeposition of Cu on Nickel Seed Layer/p-Si in Buft Cell

This paper describes the electrochemical deposition of Cu by galvanostatic method on p-Si with high deposition rate. To prevent the diffusion of Cu into Si, a thin layer of Ni is used as a diffusion barrier. A novel bath i.e., high pH Nickel sulphate bath without reducing agent was used for the galvanic reaction to form a Ni seed layer. The SEM images show the thickness of smooth and dense Ni film is in the range of 190-200 nm. Resistance of the Ni-pSi was found to be ~0.28 Ω/sq by four point probe which is lower than the resistance of Si i.e, ~108 Ω/sq. Copper was deposited on this seed layer of Ni by applying a high electric field across the wafer by placing it between a copper plating bath and an acid electrolyte. A high DC voltage was applied between a copper sheet placed in the copper bath and a platinum sheet placed in the acid electrolyte. A deposition rate of about 3.85 um/min of Cu on Ni-pSi was achieved and the film showed good adhesion. This electrochemical reaction involves silicon dissolution from one face and simultaneous copper deposition on the other. SEM images show the compact and smooth Cu film having ~3.85 um thicknesses. This experimental value of the thickness is in agreement with the theoretical value expected for 100% current efficiency. The resistance of electroplated Cu film on Ni/p-Si was measured by four point probe and found to be 0.07 Ω/sq. Fig: a and b: SEM image (Surface and Cross sectional) of Ni/p-Si c and d: SEM image (Surface and Cross sectional) of Cu on Ni-pSi

Synergistic effects occurring between water glasses and urea/ammonium dihydrogen phosphate pair for enhancing the flame retardancy of cotton

Cotton fabrics have been treated with two different finishing compositions based on urea (U) and ammonium dihydrogen phosphate (AP) in order to enhance their flame retardancy properties, particularly referring to the resistance to a flame application (namely, Limiting Oxygen Index tests) and to an irradiative heat flux of 35 kW/m2 (by cone calorimetry). The collected results have proven a remarkable increase of cotton flame resistance: indeed, the fabrics treated with the high concentrated bath showed a LOI increase of 121 % (from 19 for neat cotton, to 42 %) and did not ignite under 35 kW/m2 heat flux. Thermogravimetry coupled with pyrolysis-combustion flow calorimetry has demonstrated efficient features of the proposed flame retardant system as char-promoter for cotton. In order to reduce the amounts of U and AP employed in the selected formulations, the use of water glasses (WG) has been explored. A very low WG amount has proven to be effective in halving U and AP contents, maintaining the same fire performances already provided by the high concentrated finishing bath. Furthermore, WG have turned out to act as synergistic species as demonstrated by evaluating the synergistic effectiveness parameter.

Ionic Liquids as New Quenching Media for Aluminium Alloys and Steels*

Abstract Quenching in vaporising liquids is mostly affected by the Leidenfrost effect, causing avoidable residual stresses and distortion. Molten salts and molten metals provide a quenching without any Leidenfrost effect, but need to be operated at high bath temperatures with a high effort for cleaning the quenched components. In this work ionic liquids (salts with melting temperatures below 100 °C) are investigated as quenching media with respect to cooling power, homogeneity and thermal stability. Aluminium and steel cylinders have been quenched in baths of different ionic liquids with varying compositions and bath temperatures showing almost no Leidenfrost effect. The time-temperature curves have been recorded and the heat transfer coefficients were determined. It was shown, that the cooling power of ionic liquids could be increased by limited water addition without any Leidenfrost effect and is sufficiently fast even for quench sensitive alloys. Further investigations on aluminium samples with a complex profile show that quenching in ionic liquids causes less distortion compared to water quenching.

Transformation of ZnO nanorods into nanotubes and their field emission studies

Synthesis of vertically well-aligned ZnO nanorods on Au coated silicon substrate by a facile electrochemical route has been carried out. The transformation of as-deposited ZnO nanorods into nanotubes was achieved via simple, single step, chemical etching process using KOH as etchant. The influence of various parameters of the etching, such as concentration of the etchant, bath temperature and duration on morphological features of the ZnO nanotubes has been investigated. It is observed that formation of ZnO nanotubes with smooth inner and outer surfaces is achieved when the etching was performed at 65°C for 1 h duration, and at higher bath temperatures and longer durations, over etching of nanorods takes place. Field emission investigations of the ZnO nanorods and nanotubes were carried out at base pressure of 1 × 10-8 mbar. The values of turn-on field, corresponding to emission current density of 1 μA/cm2 were observed to be 7.2 V/μm and 8.4 V/μm, corresponding to ZnO nanorods and nanotubes emitter respectively, and emission current density of ~ 352.5 μA/cm2 has been drawn from the ZnO nanotubes emitter at an applied field of 13.77 V/μm. The ZnO nanotubes emitter exhibits excellent emission current stability at the preset value of 1 μA over duration of 3 h, indicating its potential as electron source for practical applications.

Thermal and electromagnetic properties ofBi2Sr2CaCu2O8intrinsic Josephson junction stacks studied via one-dimensional coupled sine-Gordon equations

We used one-dimensional coupled sine-Gordon equations combined with heat diffusion equations to numerically investigate the thermal and electromagnetic properties of a 300 $\ensuremath{\mu}\mathrm{m}$ long intrinsic Josephson junction stack consisting of $N=700$ junctions. The junctions in the stack are combined with $M$ segments where we assume that inside a segment all junctions behave identically. Most simulations are for $M=20$. For not too high bath temperatures there is the appearance of a hot spot at high-bias currents. In terms of electromagnetic properties, robust standing-wave patterns appear in the current density and electric field distributions. These patterns come together with vortex/antivortex lines across the stack that correspond to $\ensuremath{\pi}$-kink states, discussed before in the literature for a homogeneous temperature distribution in the stack. We also discuss scaling of the thermal and electromagnetic properties with $M$, on the basis of simulations with $M$ between 10 and 350.

Comparative Studies of Silicon Dissolution in Molten Aluminum Under Different Flow Conditions, Part I: Single-Phase Flow

Following on a study of Si dissolution in molten Al, the effect of gas agitation is examined. The effects of gas flow rate, liquid bulk velocity, the position of a top injection lance, and bath temperature on the dissolution rate are quantified. A higher gas flow rate produced larger bubbles while bubble frequency remained relatively unchanged. This resulted in larger bubble-induced fluctuating velocities which in turn increased the dissolution rate. At lower bulk velocities, the effect of gas agitation is localized around the lance. By increasing the velocity, the effect of gas agitation is transported further into the bath. The dissolution rate enhancement varies with increasing bulk velocity, and explanations are provided. When combined with a bulk flow, gas agitation increases the dissolution rate regardless of lance position. Also, the enhancement of dissolution rate due to gas injection decreases at higher superheats, as the higher bath temperature increases the mass boundary thickness. In addition, the dissolution rate without gas agitation (single-phase flow) and with gas agitation (two-phase flow) is compared in terms of mean mass transfer coefficients. It was found that for the same liquid bulk velocities, the mean mass transfer coefficients are higher in two-phase flow than in single-phase flow. Finally, an increment to the single-phase flow bulk velocity that would be required to gain parity with the two-phase flow dissolution rate rise is demonstrated.

17-3 The effects of the high concentration carbon-dioxide water foot bath for patients after stroke: A within-subject comparison study

17-3 The effects of the high concentration carbon-dioxide water foot bath for patients after stroke: A within-subject comparison study

Cu electroplating chemistry and process enabling rapid TSV filling with long bath life

Through-silicon via (TSV) filling with electroplated Cu with short plating times and long bath life remains a challenge within the semiconductor and electronic packaging industries. TSVs are the primary enabler for advanced 3D architectures such as hybrid memory cubes, wide IO DDR memory, as well as chip interconnections through interposers. The TSV needs to be completely filled with void-free Cu for high reliability. Organic additives are used to achieve a bottom-up, superconformal filling profile, required for void-free filling in high aspect ratio vias. The development and selection of the proper organic additives, optimized plating process, and implementation of advanced bath control techniques enable short TSV electroplating times, while also allowing for robust operation and high bath stability. Dow's INTERLINK™ 9200 Cu TSV plating bath with the Applied Materials TSPlus plating system allows 10×100 μm vias to be filled in less than 1 hour and 5×50 μm vias filled in under 20 minutes while having a bath life greater than 40 A hr L-1 in continuous operation. This combination also exhibits low overburden for stress management, CMP cost reductions, and high reliability.

Theory of the formation of the electric double layer at the ion exchange membrane-solution interface.

This work aims to extend the study of the formation of the electric double layer at the interface defined by a solution and an ion-exchange membrane on the basis of the Nernst-Planck and Poisson equations, including different values of the counter-ion diffusion coefficient and the dielectric constant in the solution and membrane phases. The network simulation method is used to obtain the time evolution of the electric potential, the displacement electric vector, the electric charge density and the ionic concentrations at the interface between a binary electrolyte solution and a cation-exchange membrane with total co-ion exclusion. The numerical results for the temporal evolution of the interfacial electric potential and the surface electric charge are compared with analytical solutions derived in the limit of the shortest times by considering the Poisson equation for a simple cationic diffusion process. The steady-state results are justified from the Gouy-Chapman theory for the diffuse double layer in the limits of similar and high bathing ionic concentrations with respect to the fixed-charge concentration inside the membrane. Interesting new physical insights arise from the interpretation of the process of the formation of the electric double layer at the ion exchange membrane-solution interface on the basis of a membrane model with total co-ion exclusion.

Clinical Disease Pattern and Drug Evaluation of Patients with Seronegative Spondyloarthritis at the Outpatient Department

Objective: There are a number of diseases in the spondyloarthritis (SpA) family. In this study, we evaluated the clinical disease pattern and drug use of outpatient department (OPD) patients with SpA. Methods: During a one-month period, we consecutively enrolled 100 patients with SpA. The diagnosis of ankylosing spondylitis (AS) was based on the modified New York criteria and that of psoriatic arthritis (PsA) followed The ClASsification of Psoriatic ARthritis (CASPAR) criteria. The new Assessment of SpondyloArthritis international Society (ASAS) classification criteria were used for the diagnosis of axial or peripheral SpA. Patients’ demographic characteristics, disease activity and laboratory tests were fully assessed. Medications currently used with the SpA family include non-steroidal anti-inflammatory drugs (NSAIDs) and TNF-α blockers. Results: A total of 100 SpA patients were consecutively enrolled in this short-term OPD survey. The male-to-female ratio of the enrolled patients was about 2:1 (66 males, 34 females). The clinical disease patterns of the 100 patients included 69 AS, 15 PsA, 12 non-radiographic axial SpA and 4 peripheral SpA. Uveitis was the most common extraarticular feature. Patients with positive HLA-B27 had higher Bath Ankylosing Spondylitis Functional Index (BASFI) scores, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores and CRP. Male AS patients seemed to have a higher CRP level and more severe sacroiliitis. AS patients receiving anti-TNFa therapy had significantly higher BASFI and BASDAI scores. AS patients had higher BASFI scores, and erythrocyte sedimentation rate (ESR) and CRP levels but no difference in BASDAI scores when compared to non-radiographic axial SpA patients. In terms of NSAIDs use, 45% of patients took cyclooxygenase-2 (COX-2) inhibitors (celecoxib, etoricoxib), 18% preferential COX-2 inhibitors (meloxicam), 30% nonselective NSAIDs (diclofenac, etodolac, naproxen), and 5% of patients used no NSAIDs. Besides, a higher percentage (33%) of our patients with SpA received regular anti-TNFα therapy (etanercept 17, adalimumab 15, golimumab 1). Conclusion: This OPD survey of Taiwan SpA patients disclosed not a small percentage (16%) of Taiwan SpA patients had either axial or peripheral SpA. The lack of significant difference in the BASDAI between AS and axial SpA suggests anti-TNFα therapy is indicated when traditional NSAIDs fail in axial SpA patients.

Problems in work participation and resource use should not be underestimated in patients with early spondyloarthritis.

To explore the effect of early spondyloarthritis (SpA) on worker participation and to investigate variables associated with work outcomes as well as the effect on resource use. Patients included in an early SpA cohort completed a questionnaire comprising items on employment status, sick leave, presenteeism, and resource use. Logistic regressions were used to investigate the associations between work status and clinical characteristics, and linear regressions were used to investigate the association between at-work productivity loss and clinical characteristics. Resource use across patient groups with different employment status was investigated with linear regression analyses. One hundred forty patients participated in our study. Of the patients, 69% were male, the mean age was 41 years, and the disease duration was 4.8 years. Twenty-six patients (19%) were not employed because of SpA. Among 114 employed patients, sick leave was reported in 28% in the previous year. Forty-one percent of the patients reported reduced productivity at work. Multivariable regression analyses showed that high Bath Ankylosing Spondylitis Metrology Index and Ankylosing Spondylitis Quality of Life score were associated with not being employed and with reduced productivity at work. Annual costs of productivity loss attributable to sick leave and presenteeism amounted to €2000 per patient. Patients who reported sick leave show a higher (health-related) resource use. After only 5 years of diagnosis, a considerable proportion of patients with SpA is not employed, and those working have substantial sick leave and productivity loss. Among patients reporting sick leave, resource use is higher. Alertness to work participation even in patients with a short disease duration is urgently needed.

17-5 Effects of high concentration carbon-dioxide foot bath on lower extremity function and walking ability in spastic paraplegia: A case report

17-5 Effects of high concentration carbon-dioxide foot bath on lower extremity function and walking ability in spastic paraplegia: A case report

High Speed Electrochemical Deposition Bath for Sn-Ag Alloy and Evaluation of Micro Solder Bump Plated on Ni-Coated Si Wafer

In flip chip packaging, especially high density interconnection, electrodeposition of Sn-Ag alloy has been attracted increasing attention from semiconductor industry as a replacement of toxic tin-lead solders. With aim of improving plating speed, life-time, and enhancing quality of micro solder bump, various electrochemical characteristics of strong acid electroplating bath composing of methane sulfonic acid (MSA), Ag-MSA, Sn-MSA, and several modification agents were investigated by using linear voltammetry techniques, cyclic voltammetric stripping (CVS) with controlled hydrodynamic condition with RDE. In addition, surface morphology, metallurgical structure and composition of Sn-Ag solder bump formed on Si wafer and deposition properties were characterized by using XRD, WDXRF, and SEM. The CVS measurements showed that suppressing the hydrogen evolution reaction at high cathodic current above 30mA/cm2 was critical, and small amount, less than 0.6 g/L, of benzylidene acetone was effective for this troublesome. The fundamental electrochemical responses revealed that the concentration of metallic complex ions, silver (I) and tin (II & IV), and its stability are crucial for better electroplating. In this study, the effects of complexing agent of thiourea, anti-oxidizer of hydroquinone, and several surfactants were also examined in terms of potential shift, current density, solution stability, and deposition rate. The results also showed that most electrochemical reactions in this bath composition are influenced by rotation speed, hence hydrodynamic conditions. With optimized bath solution, electroplating parameters, such as current efficiency, deposition rate, and elemental decay, and bath lifetime were also measured on micro-patterned Si wafer, and plating performance was compared with electrochemical properties. The optimized plating bath showed high deposition rate of 0.8μm/min/ASD, longer lifetime of 95 AH/L, proper eutectic alloy composition of 3.5 w/o and suitable for micro solder bump size of less than 20 μm. In this study, the relation of electrochemical and deposition characteristics with various additives and electrical properties of micro solder bumps will be discussed.

High-performance chemical-bath deposited CdS thin-film transistors with ZrO2 gate dielectric

We demonstrate high performance chemical bath deposited CdS thin-film transistors (TFTs) using atomic layer deposited ZrO2 based high-k gate dielectric material. Our unique way of isolation of the CdS-based TFTs devices yielded significantly low leakage current as well as remarkable lower operating voltages (<5 V) which is four times smaller than the devices reported on CdS-based TFTs using SiO2 gate dielectric. Upon thermal annealing, the devices demonstrate even higher performance, including μFE exceeding 4 ± 0.2 cm2 V−1S−1, threshold voltage VT of 3.8 V, and Ion-off of 104–105, which hold much promise for applications in future electronic and optical devices.

Non-catalytic liquefaction of microalgae in sub-and supercritical acetone

Abstract In the present study, a microalga ( Chlorella pyrenoidosa ) was treated in sub/supercritical acetone in the absence of catalyst by using a high pressure bath reactor. Influence of process variables such as temperature (varied from 170 to 350 °C), acetone/microalga ratio (varied from 2/2.5 to 16/2.5), and time (varied from 5 to 120 min) on the yields of product factions and properties of biocrude has been studied. Temperature was the most influential factor affecting the products yield and properties of the biocrude, and the highest biocrude yield of 60.1 wt.% was achieved at 290 °C. Addition of acetone not only promoted the conversion of microalga but also favored the biocrude yield due to the incorporation of acetone into the biocrude. Furthermore, liquefaction of microalga in acetone made the conversion milder that than of in water. The biocrude was less viscous than that of oil produced from hydrothermal liquefaction under otherwise identical reaction conditions. The biocrudes, which contained significant carbon and hydrogen than that of the original algal biomass, had higher heating values ranging from 28.7 to 37.1 MJ/kg. The most abundant compounds for the biocrude are unsaturated fatty acids (9,12,15-octadecatrienoic acid) and hydrocarbons (2-hexadecene, 3,7,11,15-tetramethyl-). CO 2 was the dominant component in the gaseous products under all experimental conditions. Deoxygenation and denitrogenation are necessary if one to expect to produce transportation fuels from this kind of biocrude.

High Concentration CO2-water Bathing Promotes A Recovery From The Muscle Fatigue Induced By Resistance Exercise

High Concentration CO2-water Bathing Promotes A Recovery From The Muscle Fatigue Induced By Resistance Exercise

ZnO nanorods for efficient third harmonic UV generation

ZnO nanorods grown by both high temperature vapour phase transport and low temperature chemical bath deposition are very promising sources for UV third harmonic generation. Material grown by both methods show comparable efficiencies, in both cases an order of magnitude higher than surface third harmonic generation at the quartz-air interface of a bare quartz substrate. This result is in stark contrast to the linear optical properties of ZnO nanorods grown by these two methods, which show vastly different PL efficiencies. The third harmonic generated signal is analysed using intensity dependent measurements and interferometric frequency resolved optical gating, allowing extraction of the laser pulse parameters. The comparable levels of efficiency of ZnO grown by these very different methods as sources for third harmonic UV generation provides a broad suite of possible growth methods to suit various substrates, coverage and scalability requirements. Potential application areas range from interferometric frequency resolved optical gating characterization of few cycle fs pulses to single cell UV irradiation for biophysical studies.

Hydrothermal flame impingement experiments. Combustion chamber design and impingement temperature profiles

The current work presents the hydrothermal flame impingement experiments conducted for the design of a hydrothermal spallation drilling nozzle. The products of hydrothermal flames of mixtures of ethanol, water and oxygen were injected as free jets in a high pressure water bath. The nozzle design was based on ideas stemming from underwater welding and cutting of metal sheets. Water entrainment in the flame-jets and the heat transfer capabilities of flames injected from various nozzles have been analyzed by measuring their impingement temperature profiles on a flat stainless steel plate. It was found that the thermal-to-kinetic energy ratio of the jet has a direct influence on the entrainment of water in it. Furthermore, the cooling water of the combustion chamber was injected in various angles to the axis of the jet resulting to different entrainment rates. It was found that higher water injection angles reduced the rate of entrainment. Finally, it was indicated that at certain operational points of the jet, its trans-critical properties had an important influence on the impingement temperatures.

Severe Hypocalcemia due to Denosumab in Metastatic Prostate Cancer.

Denosumab is a monoclonal antibody used for prevention of skeletal-related events (SREs) in patients with bone metastases from solid tumors. Hypocalcemia is a rare and dangerous side effect of the drug Denosumab. We present a case of a patient with metastatic prostate cancer who developed severe hypocalcemia after the administration of the drug. The patient's vitamin D levels were low when checked after administration of the drug, which likely predisposed him to the development of hypocalcemia. He was placed on high doses of oral and intravenous (IV) calcium and vitamin D without any appreciable response in the serum calcium level. His ionized calcium remained below 0.71 mmol/L despite very high doses of oral and IV calcium supplements. During the hospital course, he developed hydronephrosis from the spread of a tumor and did not want to undergo percutaneous nephrostomy tube placement; therefore, it was decided to dialyse him for acute renal failure and to correct his hypocalcemia. Checking calcium and vitamin D levels prior to the administration of Denosumab is vital in preventing hypocalcemia. If hypocalcemia is severe and not responsive to high doses of vitamin D, oral and IV calcium, then hemodialysis with a high calcium bath can correct this electrolyte abnormality.

TRPV1 in Salivary Gland Epithelial Cells Is Not Involved in Salivary Secretion via Transcellular Pathway.

Transient receptor potential vanilloid subtype 1 (TRPV1) was originally found in sensory neurons. Recently, it has been reported that TRPV1 is expressed in salivary gland epithelial cells (SGEC). However, the physiological role of TRPV1 in salivary secretion remains to be elucidated. We found that TRPV1 is expressed in mouse and human submandibular glands (SMG) and HSG cells, originated from human submandibular gland ducts at both mRNA and protein levels. However, capsaicin (CAP), TRPV1 agonist, had little effect on intracellular free calcium concentration ([Ca2+]i) in these cells, although carbachol consistently increased [Ca2+]i. Exposure of cells to high temperature (>43℃) or acidic bath solution (pH5.4) did not increase [Ca2+]i, either. We further examined the role of TRPV1 in salivary secretion using TRPV1 knock-out mice. There was no significant difference in the pilocarpine (PILO)-induced salivary flow rate between wild-type and TRPV1 knock-out mice. Saliva flow rate also showed insignificant change in the mice treated with PILO plus CAP compared with that in mice treated with PILO alone. Taken together, our results suggest that although TRPV1 is expressed in SGEC, it appears not to play any direct roles in saliva secretion via transcellular pathway.