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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]

A study was conducted to analyze a novel design theory using a phase inverter for the systematic size reduction and band broadening of a uniplanar hybrid ring coupler. The effective bandwidth of a new reverse-phase hybrid ring coupler can be increased by 28% supporting a return loss of 20 dB. A category of uniplanar phase inverters was then examined. Results indicated that the design supports freedom and tradeoff associated with designing broadband/narrow-band and size-reduced couplers.

An enhanced spectral domain approach (SDA) is developed for analysis of complex quasi-planar transmission lines. The method is based on a combination of spectral domain formulation and power conservation theorem. The relationship between electric and magnetic fields is established inside dielectric layers by using the conventional SDA while characteristic equation related to interface conditions is derived through the power conservation theorem. Maintaining the inherent advantages of the SDA, this technique is able to easily handle more complex quasi-planar structures. Generalized power formulation is also presented to calculate characteristic impedance. Convergence behavior is discussed considering the nature of power conservation. Various finlines with finite thickness of conductors are analyzed to demonstrate its applications.

Propagation characteristics of fundamental and higher-order modes are determined in coupled slotlines with three suspended mounting schemes (pedestal, groove, inverse pedestal) for wideband applications of microwave and millimeter-wave integrated circuits. The analysis is based on a novel enhanced spectral domain approach (ESDA) that combines essentially the conventional spectral domain technique with the power conservation theorem. Numerical results, considering also the influence of finite conductor thickness, are presented for propagation constants and characteristic impedance of the fundamental modes. Effects of different suspended mounting schemes on cutoff frequencies of first higher-order even and odd modes are discussed in detail. Field profiles of the fundamental modes in coupled slotlines with and without pedestals are shown. The inherent mechanism of mode transition is explained with respect to different pedestal sizes, indicating that the monomode bandwidth can be extended by appropriately choosing the dimension of pedestal in coupled slotlines.

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]