Redeposition mechanism on silicon oxide layers during selective etching process in 3D NAND manufacture

Zihan Zhou,Yunwen Wu,Huiqin Ling,Jie Guo,Su Wang,Ming Li 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.119 No.-

3D NAND flash memory with vertically stacked cells has been developed to break through the limits oftechnology nodes. However, during the selective etching process, it is difficult to ensure the byproductsdiffuse away from the trenches in the multistacked layers. Once saturated, the byproduct causes abnormalredeposition on the SiO2 layers. This problem has restricted the development of high-density 3DNAND memory. To solve this problem, the composition and formation mechanism of the redepositedlayer must be clarified. In this study, a ternary-wafer system comprising a Si3N4/SiO2/Si3N4 stack was fabricatedto study the redeposition mechanism, and the morphology, elastic properties, and chemical compositionof the redeposited layer were clarified. The redeposited layer consists of spherical particles withelastic surfaces (average Young’s modulus of 24.17 GPa). The particles were confirmed to comprise colloidalsilica gel covered by silanols. By considering the chemistry of silica, the redeposition mechanismwas proposed as follows: colloidal silica gel is formed by the aggregation of silicic acids from Si3N4 etching,which adsorb onto the SiO2 layer through oxide bridges and hydrogen bonding. Our work will contributeto the development of high-density 3D NAND memory.

Influences of weaving architectures and impact locations on the ballistic resistance of UHMWPE fabric

Zihan Zhu,Hu Zhou,Xiangshao Kong,Fang Liu,Yongqiang Zhang,Cheng Zheng,Weiguo Wu 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12

This study is devoted to reveal the influence of weaving architectures and impact locations on the ballistic resistance of UHMWPE (ultrahigh high molecular weight polyethylene) fabrics. Firstly, a mesoscopic model of UHMWPE fabric is established and the accuracy of the numerical method is verified. Subsequently, the models with different weaving architectures are further established, and the impact resistance performances are evaluated. Finally, the influence factors on the fabric ballistic resistance is explored. It is proved that the ballistic resistance of UHMWPE fabric mainly dominated by the tensile strength of yarn under highvelocity impact. The plain fabric shows best anti-ballistic performance, while basket and woven fabric are slightly inferior. The damage pattern of fabrics with different weaving architectures changes greatly. In addition, this study proposes a residual impact velocity correction model for projectile based on the probability distribution of impact positions, which can better characterize the protective ability of fiber fabrics.

A New Method for Measuring Refractive Index with a Laser Frequency-shifted Feedback Confocal Microscope

Zhou, Borui,Wang, Zihan,Shen, Xueju Optical Society of Korea 2020 Current Optics and Photonics Vol.4 No.1

In this paper, a new method is presented to measure the refractive index of single plain glass or multilayered materials, based on a laser frequency-shifted confocal feedback microscope. Combining the laser frequency-shifted feedback technique and the confocal effect, the method can attain high axial-positioning accuracy, stability and sensitivity. Measurements of different samples are given, including N-BK7 glass, Silica plain glass, and a microfluidic chip with four layers. The results for N-BK7 glass and Silica plain glass show that the measurement uncertainty in the refractive index is better than 0.001. Meanwhile, the feasibility of this method for multilayered materials is tested. Compared to conventional methods, this system is more compact and has less difficulty in sample processing, and thus is promising for applications in the area of refractive-index measurement.

Customized maxillary incisor position relative to dentoskeletal and soft tissue patterns in Chinese women: A retrospective study

Zhou Xueman,Zheng Yingcheng,Zhang Zhenzhen,Zhang Zihan,Wu Lina,Liu Jiaqi,Yang Wenke,Wang Jun 대한치과교정학회 2022 대한치과교정학회지 Vol.52 No.2

Objective: To provide reliable prediction models based on dentoskeletal and soft tissue variables for customizing maxillary incisor positions and to optimize digitalized orthodontic treatment planning. Methods: This study included 244 Chinese women (age, 18–40 years old) with esthetic profiles after orthodontic treatment with fixed appliances (133 in group I: 1° ≤ The angle between the nasion [N]-A point [A] plane and the N-B point [B] plane [ANB] ≤ 4°; 111 in group II: 4° < ANB ≤ 7°). Dental, skeletal, and soft tissue measurements were performed on lateral cephalograms of the participants. Correlation and multiple linear regression analyses were used to determine the influence of dentoskeletal and soft tissue variables on maxillary incisor position. Results: The ideal anteroposterior position of the maxillary incisor varied between sagittal skeletal patterns. The position of the maxillary incisor correlated with the sagittal discrepancy between the maxilla and the mandible (ANB), protrusion of the midface, nasal tip projection, development of the chin, and inclination of both the maxillary and mandibular incisors. Distance from the maxillary central incisor to nasion-pogonion plane predicted using multiple linear regression analysis was accurate and could be a practical measurement in orthodontic treatment planning. Conclusions: Instead of using an average value or norm, orthodontists should customize a patient’s ideal maxillary incisor position using dentoskeletal and soft tissue evaluations.

A New Method for Measuring Refractive Index with a Laser Frequency-shifted Feedback Confocal Microscope

Borui Zhou,Zihan Wang,Xueju Shen 한국광학회 2020 Current Optics and Photonics Vol.4 No.1

In this paper, a new method is presented to measure the refractive index of single plain glass or multilayered materials, based on a laser frequency-shifted confocal feedback microscope. Combining the laser frequency-shifted feedback technique and the confocal effect, the method can attain high axialpositioning accuracy, stability and sensitivity. Measurements of different samples are given, including N-BK7 glass, Silica plain glass, and a microfluidic chip with four layers. The results for N-BK7 glass and Silica plain glass show that the measurement uncertainty in the refractive index is better than 0.001. Meanwhile, the feasibility of this method for multilayered materials is tested. Compared to conventional methods, this system is more compact and has less difficulty in sample processing, and thus is promising for applications in the area of refractive-index measurement.

병원의 서비스품질 및 서비스가치가 고객만족도에 미치는 영향: 한·중 종합병원의 비교분석을 중심으로

( Shi Chen ),( Zihan Zhou ),정진섭 ( Jin Sup Jung ) 한국유통경영학회 2021 유통경영학회지 Vol.24 No.4

Purpose: The goal of this study seeks to consider the impact of the hospital’s service quality and perceived service value on customer satisfaction. To this end, the two regions were compared and analyzed by customers visiting general hospitals in Osong (Korea) and Wuhan (China). Research design, data, and methodology: The independent variables (or service qualities) are set as assurance, responsiveness, empathy, tangibles, reliability, and accessibility, the dependent variable is customer satisfaction, and the mediating variable is (perceived) service value. Finally, convenience of facilities was set as a moderating variable. In this study, questionnaire design were constructed based on the model, and then empirical analyses were performed. Data were collected through questionnaires for customers who visited general hospitals in Osong, Korea and Wuhan, China. Multiple regression analyses were used for comparative analyses of the two regions. Results: Regarding the effect of ‘service qualities’ on ‘service value’, in Korea, ‘responsiveness’ and ‘tangibles’ did not show significant, while, in China, ‘assurance’ and ‘tangibles’ did not. Regarding the effect of independent variables on dependent variable, Korea did not show statistical significance in ‘responsiveness’, ‘empathy’ and ‘tangibles’, while China did not show in ‘responsiveness’. On the other hand, the mediating effect of ‘service value’ between the service quality and customer satisfaction was confirmed in both Korea and China, while the moderating effect of ‘convenience of facilities’ was not statistically significant in both Korea and China. Implications: Based on the empirical results, service quality and service value have a significant impact on customer satisfaction, so differentiation strategies by region for each characteristics of service quality will be needed. In addition, because the mediating effect of ‘service value’ is important, special attention should be paid to the perceived ‘service value.’ Finally this study suggested relevant practical and policy implications.

Removal of fluoroquinolone antibiotics by adsorption of dopamine-modified biochar aerogel

Hongjuan Bai,Qiaofei Zhang,Xuan Zhou,Junhang Chen,Zihan Chen,Zhuangzhuang Liu,Jun Yan,Jing Wang 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.1

As emerging contaminants used for treating various tract infections, fluoroquinolones (such as enoxacin, ofloxacin, etc.) enter water bodies via point-source discharges of wastewater treatment plants and many of them raise environmental and health concerns. Herein, a novel adsorbent, derived from a useful renewable low-cost grapefruit peel, was prepared to investigate the adsorption behavior of fluoroquinolone antibiotics (enoxacin and ofloxacin). The obtained adsorbent was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), X-ray diffraction (XRD) and thermo-gravimetric analysis and differential scanning calorimetry (TG-DSC). Further, the equilibrium sorption of the adsorption process was analyzed with isotherm models and kinetic models. Under optimal adsorption conditions, equilibrium data conformed to the Elovich model, and the kinetics of adsorption was fitted well with Redlich-Peterson model. Combined with thermodynamic analysis, electrostatic interaction, hydrogen bond, π-π stacking interaction were the possible adsorption mechanisms for both fluoroquinolone antibiotics onto the novel adsorbent. This work explored a promising adsorbent for the elimination of fluoroquinolone antibiotics in environmental remediation.

Ginseng-derived type I rhamnogalacturonan polysaccharide binds to galectin-8 and antagonizes its function

Yi Zheng,Yunlong Si,Xuejiao Xu,Hongming Gu,Zhen He,Zihan Zhao,Zhangkai Feng,Jiyong Su,Kevin H. Mayo,Yifa Zhou,Guihua Tai The Korean Society of Ginseng 2024 Journal of Ginseng Research Vol.48 No.2

Background: Panax ginseng Meyer polysaccharides exhibit various biological functions, like antagonizing galectin-3-mediated cell adhesion and migration. Galectin-8 (Gal-8), with its linker-joined N- and C-terminal carbohydrate recognition domains (CRDs), is also crucial to these biological processes, and thus plays a role in various pathological disorders. Yet the effect of ginseng-derived polysaccharides in modulating Gal-8 function has remained unclear. Methods: P. ginseng-derived pectin was chromatographically isolated and enzymatically digested to obtain a series of polysaccharides. Biolayer Interferometry (BLI) quantified their binding affinity to Gal-8, and their inhibitory effects on Gal-8 was assessed by hemagglutination, cell migration and T-cell apoptosis. Results: Our ginseng-derived pectin polysaccharides consist mostly of rhamnogalacturonan-I (RG-I) and homogalacturonan (HG). BLI shows that Gal-8 binding rests primarily in RG-I and its β-1,4-galactan side chains, with sub-micromolar K_D values. Both N- and C-terminal Gal-8 CRDs bind RG-I, with binding correlated with Gal-8-mediated function. Conclusion: P. ginseng RG-I pectin β-1,4-galactan side chains are crucial to binding Gal-8 and antagonizing its function. This study enhances our understanding of galectin-sugar interactions, information that may be used in the development of pharmaceutical agents targeting Gal-8.