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Transparent conductive electrodes (TCEs) are indispensable components of various optoelectronic devices such as displays, touch screen panels, solar cells, and smart windows. To date, the fabrication processes for metal mesh‐based TCEs are either costly or having limited resolution and throughput. Here, a two‐step surface energy‐directed assembly (SEDA) process to efficiently fabricate high resolution silver meshes is introduced. The two‐step SEDA process turns from assembly on a functionalized substrate with hydrophilic mesh patterns into assembly on a functionalized substrate with stripe patterns. During the SEDA process, a three‐phase contact line pins on the hydrophilic pattern regions while recedes on the hydrophobic non‐pattern regions, ensuring that the assembly process can be achieved with excellent selectivity. The necessity of using the two‐step SEDA process rather than a one‐step SEDA process is demonstrated by both experimental results and theoretical analysis. Utilizing the two‐step SEDA process, silver meshes with a line width down to 2 µm are assembled on both rigid and flexible substrates. The thickness of the silver meshes can be tuned by varying the withdraw speed and the assembly times. The assembled silver meshes exhibit excellent optoelectronic properties (sheet resistance of 1.79 Ω/□, optical transmittance of ≈92%, and a FoM value of 2465) as well as excellent mechanical stability. The applications of the assembled silver meshes in touch screen panels and thermal heaters are demonstrated, implying the potential of using the two‐step SEDA process for the fabrication of TCEs for optoelectronic applications. [ABSTRACT FROM AUTHOR]

The synthesis of CeO2 nanoparticles for CeO2 based slurry gains continuous emphasis on improving its performance in the chemical mechanical polishing of dielectric materials. Urea was selected to dominate the growth and morphology during the calcination process. Thermogravimetry experiments were used to analyze the the decomposition behavior. Particle morphology and size were analyzed. Crystalline phase information and surface valence were used to compare the differences in surface physical and chemical properties of ceria by different synthesis process. The CeO2 nanoparticles synthesized with urea were dispersed in water as slurry. The particle sizes of CeO2 were measured by dynamic light scattering. The Zeta potential of CeO2 dispersion were measured to show dispersing performance. The CeO2 nanoparticles synthesized with urea condensation show good monodisperse properties. The material removal rate of silicon oxide and surface quality after chemical mechanical polishing were selected to evaluate the chemical mechanical polishing performance. The CeO2 nanoparticles synthesized with urea condensation not only yielded better surface quality results than the commercial slurry but also showed a 153% (pH = 4) and 100% (pH = 10) increase in the material removal rate of silicon oxide compared to commercial. [ABSTRACT FROM AUTHOR]

Endpoint detection is an important technology in chemical mechanical polishing (CMP), which is used to capture the material interface and compensate the variations of consumables and incoming wafer thickness. This paper aimed to apply optical detection in metal CMP. An in situ optical measurement system was developed for a 12-inch CMP tool. Kinematic analysis of the scanning trajectory of the laser device indicated the relative position relationship between the device and the wafer. Average optical data within the wafer described the material removal of metal CMP. Furthermore, optical data and location described the non-uniformity of the entire wafer surface. In this research, the polishing condition and the residual of the wafer edge are characterized by optical trace. Pauta Criterion is used to discriminate the inflexion point of the material interface. The results reveal that the interface capture is accurate and effective. [ABSTRACT FROM AUTHOR]

Expression of interleukin-23 receptor (IL-23R) and IL-17 in urinary bladder carcinoma (UBC) was investigated to explore the correlations with prognosis. IL-23/IL-17 axis significantly inhibited the development of inflammatory bowel disease. Thirty patients with UBC were enrolled in Zhengzhou Central Hospital Affiliated to Zhengzhou University from September 2013 to September 2014. Tumor tissue and adjacent healthy tissue were collected, and the levels of IL-23R and IL-17 mRNA were detected by RT-PCR. Thirty healthy people were also selected to serve as normal control group. Serum levels of IL-23R and IL-17 in serum of UBC patients and normal controls were detected by ELISA, and the correlations with clinical features of UBC were analyzed. Pearson's correlation analysis was used to analyze the correlation between IL-23R and IL-17 protein expression. Follow-up study was performed by phone or during patient's visit to out-patient department. Overall survival (OS) and disease-free survival (DFS) curves were plotted by Kaplan-Meier method to analyze the correlation between expression of IL-23R and IL-17 and survival time. ROC curve was used to detect the diagnostic values of IL-23R and IL-17 protein for UBC. Levels of IL-23R and IL-17 mRNA in UBC tissue were 3.26 and 2.65 times higher than those in adjacent tissue (P<0.05), and serum levels of IL-23R and IL-17 protein in UBC patients were significantly higher than those in normal control group. Protein expression levels of IL-23R and IL-17 were correlated with clinical stage and lymph node metastasis in UBC patients (P<0.05), and Cox hazard model showed that L-23R and IL-17 expression may be independent factors for UBC (P<0.05), and high expression levels of IL-23R and IL-17 significantly shortened the OS and DFS (P<0.05). Serum levels of IL-23R and IL-17 can be used to effectively diagnose clinical stage and lymph node metastasis of UBC patients, and the combined diagnosis has a higher sensitivity and specificity than the diagnosis using a single factor. These findings indicated that expression levels of IL-23R and IL-17 were increased in tumor tissue and serum of UBC patients, and the increased expression levels of IL-23R and IL-17 were correlated with poor prognosis. Detection of IL-23R and IL-17 levels has certain clinical significance in the diagnosis and prognosis of UBC. [ABSTRACT FROM AUTHOR]

In the via-middle process of 3-D integrated circuit manufacturing, through-silicon via (TSV) annealing causes mechanical stress not only to its surrounding structures, including liner and landing pad, but also the contacts nearby. This process may result in a noticeable pop-out in TSVs and/or contacts, thus complicating the subsequent chemical mechanical polishing (CMP). In addition, residual stress may cause delamination or crack. In this paper, we conducted detailed simulations of the residual stress and pop-out mechanisms for TSVs and neighboring contacts. Our primary focus was on the interplay of TSV-induced and contact-induced stresses and their combined impact on pop-out height. In addition, we conducted a sensitivity analysis of key parameters, including distance, plasticity, annealing temperature, and the distribution of neighboring contacts. This paper showed that these parameters notably affect the stress and the pop-out of TSVs and contacts. This in turn is expected to complicate the subsequent CMP steps. Finally, we applied the linear superposition method to predict stress and validated its accuracy by comparing the results with finite element analysis simulation. The results of the comparison demonstrated that the superposition method was accurate. Therefore, it could be used to predict the stress for full-chip design. [ABSTRACT FROM PUBLISHER]

Effects of catalyst concentration and ultraviolet intensity on chemical mechanical polishing (CMP) of GaN were deeply investigated in this paper. Working as an ideal homogeneous substrate material in LED industry, GaN ought to be equipped with a smooth and flat surface. Taking the strong chemical stability of GaN into account, photocatalytic oxidation technology was adopted in GaN CMP process to realize efficient removal. It was found that, because of the improved reaction rate of photocatalytic oxidation, GaN material removal rate (MRR) increases by a certain extent with catalyst concentration increasing. Cross single line analysis on the surface after polishing by Phase Shift MicroXAM-3D was carried out to prove the better removal effect with higher catalyst concentration. Ultraviolet intensity field in H 2 O 2 -SiO 2 -based polishing system was established and simulated, revealing the variation trend of ultraviolet intensity around the outlet of the slurry. It could be concluded that, owing to the higher planarization efficiency and lower energy damage, the UV lamp of 125 W is the most appropriate lamp in this system. Based on the analysis, defects removal model of this work was proposed to describe the effects of higher catalyst concentration and higher power of UV lamp. [ABSTRACT FROM AUTHOR]

GaN is so hard and so chemically inert that it is difficult to obtain a high material removal rate (MRR) in the chemical mechanical polishing (CMP) process. This paper discusses the application of photocatalytic oxidation technology in GaN planarization. Three N-type semiconductor particles (TiO 2 , SnO 2 , and Fe 2 O 3 ) are used as catalysts and added to the H 2 O 2 –SiO 2 -based slurry. By optical excitation, highly reactive photoinduced holes are produced on the surface of the particles, which can oxidize OH − and H 2 O absorbed on the surface of the catalysts; therefore, more OH* will be generated. As a result, GaN MRRs in an H 2 O 2 –SiO 2 -based polishing system combined with catalysts are improved significantly, especially when using TiO 2 , the MRR of which is 122 nm/h. The X-ray photoelectron spectroscopy (XPS) analysis shows the variation trend of chemical composition on the GaN surface after polishing, revealing the planarization process. Besides, the effect of pH on photocatalytic oxidation combined with TiO 2 is analyzed deeply. Furthermore, the physical model of GaN CMP combined with photocatalytic oxidation technology is proposed to describe the removal mechanism of GaN. [ABSTRACT FROM AUTHOR]

Adsorption removal of Cu (II) and Pb (II) on cross-linked chitosan/Al13-pillared montmorillonite (CCPM) was examined in solutions. The chitosan dosage was drastically reduced in the new nanocomposite, which is made from the treated clay (Al13-pillared montmorillonite). Several important parameters that influenced the adsorption of Cu (II) and Pb (II) ions, such as cross-linked chitosan-to-clay ratio, pH, temperature, initial concentration, dosage, and contact time effect, were systematically investigated. Result showed that in the nanocomposite with cross-linked chitosan-to-clay ratio of 0.45:1, the maximum removal efficiencies of Cu (II) [pH 6.5, dosage 10 g/L, initial Cu (II) concentration 100 mg/L, contact time 2 h, 298 K] and Pb (II) [pH 6.0, dosage 5 g/L, initial Pb (II) concentration 100 mg/L, contact time 2 h, 298 K] were 96.0% and 99.5%, respectively. Kinetic and isotherm studies have indicated that the adsorption process of Cu (II) or Pb (II) nanocomposites was better fitted by the pseudo-second-order equation and the Freundlich equation, with chemical adsorptions as the rate-limiting step. The metal–ion affinity to the functional groups of CCPM followed the order Pb (II) > Cu (II). The thermodynamic parameters ΔHand ΔSvalues showed that the sorption process of Cu (II) or Pb (II) was spontaneous (ΔG < 0), was endothermic (ΔH < 0), and had decreased entropy (ΔS < 0). HNO3(0.1 M) could be a good desorbent in the recovery of metal ions after adsorption and regeneration of the adsorbent. [ABSTRACT FROM AUTHOR]

When the feature size of integrated circuit continues to shrink below 14 nm, ruthenium (Ru) has become one of the most promising candidates for the application of novel barrier layer. To reveal the material removal mechanism of Ru during chemical mechanical polishing (CMP), surface characteristics of Ru in KIO 4 -based slurry were investigated. The corrosion behavior of ruthenium was measured by the surface chemistry and morphology analysis. Then the mechanical properties of the passivated/corroded surface were evaluated by AES and tribocorrosion experiments. CMP experiments were carried out to make clear the effects of surface property during polishing. It was found that the Ru surface chemistry and mechanical properties vary obviously as a function of slurry pH. In neutral slurries, the Ru surface is covered with RuO 2 ·2H 2 O/RuO 3 inhomogeneous passivation films, with the highest material removal rate obtained during the CMP process. It could be concluded that the material removal mechanism largely depends on the slurry pH values. In near neutral slurries, Ru is passivated with thick and heterogeneous oxides film, which proves the easiest to be mechanically removed during polishing. The weak alkaline slurry is preferred in order to achieve desirable polishing rate as well as avoid the formation of toxic RuO 4 . [ABSTRACT FROM AUTHOR]