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10. Nanoparticle Engineering for Chemical-Mechanical Planarization

Author

Paik, Ungyu and Park, Jea-Gun

Subjects
Material Sciences, bic Book Industry Communication::T Technology, engineering, agriculture::TB Technology: general issues::TBN Nanotechnology
Abstract

Increasing reliance on electronic devices demands products with high performance and efficiency. Such devices can be realized through the advent of nanoparticle technology. This book explains the physicochemical properties of nanoparticles according to each step in the chemical mechanical planarization (CMP) process, including dielectric CMP, shallow trend isolation CMP, metal CMP, poly isolation CMP, and noble metal CMP. The authors provide a detailed guide to nanoparticle engineering of novel CMP slurry for next-generation nanoscale devices below the 60nm design rule. This comprehensive text also presents design techniques using polymeric additives to improve CMP performance.

Published
2009
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14. The Perfect Imperfections of Perovskite Oxide Catalysts in the Aspect of Defect Equilibria.

Author

Christy, Maria, Choi, Seunggun, Kwon, Jiseok, Jeong, Jinwoo, Paik, Ungyu, and Song, Taeseup

Subjects
OXYGEN vacancy, CHEMICAL kinetics, ELECTROCATALYSIS kinetics, OXYGEN evolution reactions, CATALYST structure, ELECTROCATALYSIS
Abstract

ABX3 (X = O) perovskite oxides are an uprising class of alternative electrocatalysts in eminent technologies like electrocatalysis, photocatalysis, thermocatalysis, and energy storage. The perquisites of perovskite oxide catalysts encompass ordered atomic structure, structural/compositional extensibility, flexible electronic structure, lucrativeness, and so on. The ingenuity to precisely control and tune the inherent properties by reconstructing their crystal structure is particularly advantageous in electrocatalysis reactions like oxygen reduction and evolution reactions (ORR and OER). Incorporating multidimensional imperfections in the presumably perfect crystal structure of the perovskite catalysts is garnering booming attention among researchers. This concept can expertly influence the electronic structure and boost the reaction kinetics during electrocatalysis. Defects or imperfections are achieved by substituting A‐ and/or B‐sites with heteroatoms or by oxygen vacancies. Defect engineering points to a promising new direction in the development of perovskite oxide catalysts. This work surveys the recent progress in defect engineering and how it plays a vital role in their design, and application in electrocatalysis, mainly ORR/OER. The architecture, dimensionality, and the types of perovskite oxides based on their cations, crystal structures, and stoichiometries are surveyed for a comprehensive understanding. This review aims to provide an extensive outlook on oxide perovskite catalysts concerning structural defects. [ABSTRACT FROM AUTHOR]

Published
2025
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15. Regulating Li electrodeposition by constructing Cu–Sn nanotube thin layer for reliable and robust anode‐free all‐solid‐state batteries.

Author

Kim, Jaeik, Lee, Seungwoo, Kim, Jeongheon, Park, Joonhyeok, Lee, Hyungjun, Kwon, Jiseok, Sun, Seho, Choi, Junghyun, Paik, Ungyu, and Song, Taeseup

Subjects
STRAINS & stresses (Mechanics), SOLID electrolytes, DENDRITIC crystals, COPPER, CRITICAL currents
Abstract

Anode‐free all‐solid‐state batteries (AF‐ASSBs) have received significant attention as a next‐generation battery system due to their high energy density and safety. However, this system still faces challenges, such as poor Coulombic efficiency and short‐circuiting caused by Li dendrite growth. In this study, the AF‐ASSBs are demonstrated with reliable and robust electrochemical properties by employing Cu–Sn nanotube (NT) thin layer (~1 µm) on the Cu current collector for regulating Li electrodeposition. LixSn phases with high Li‐ion diffusivity in the lithiated Cu–Sn NT layer enable facile Li diffusion along with its one‐dimensional hollow geometry. The unique structure, in which Li electrodeposition takes place between the Cu–Sn NT layer and the current collector by the Coble creep mechanism, improves cell durability by preventing solid electrolyte (SE) decomposition and Li dendrite growth. Furthermore, the large surface area of the Cu–Sn NT layer ensures close contact with the SE layer, leading to a reduced lithiation overpotential compared to that of a flat Cu–Sn layer. The Cu–Sn NT layer also maintains its structural integrity owing to its high mechanical properties and porous nature, which could further alleviate the mechanical stress. The LiNi0.8Co0.1Mn0.1O2 (NCM)|SE|Cu–Sn NT@Cu cell with a practical capacity of 2.9 mAh cm−2 exhibits 83.8% cycle retention after 150 cycles and an average Coulombic efficiency of 99.85% at room temperature. It also demonstrates a critical current density 4.5 times higher compared to the NCM|SE|Cu cell. [ABSTRACT FROM AUTHOR]

Published
2024
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37. 10 mAh cm−2 Cathode by Roll‐to‐Roll Process for Low Cost and High Energy Density Li‐Ion Batteries.

Author

Kim, Jiwoon, Park, Keemin, Kim, Minsung, Lee, Hyungjun, Choi, Junghyun, Park, Ho Bum, Kim, Hansu, Jang, Jaeyoung, Kim, Young‐Hoon, Song, Taeseup, and Paik, Ungyu

Subjects
ENERGY density, LITHIUM-ion batteries, ELECTRIC batteries, CATHODES, ENERGY industries, MANUFACTURING processes, POLYTEF
Abstract

Roll‐to‐roll dry processing enables the manufacture of high energy density and low cost Li‐ion batteries (LIBs). However, as the thickness of the electrode fabricated by dry processing becomes greater (≥10 mAh cm−2), Li‐ion migration resistance (Rion) and charge‐transfer resistance (Rct) in the electrode dramatically increase due to long diffusion lengths for Li‐ion and electron. Therefore, it is important to reduce diffusion lengths in the electrode to achieve high energy density LIBs. The dry electrode with a high areal capacity of 10 mAh cm−2 and low resistance can be achieved by following three characteristics. First, the fibrillization behavior of polytetrafluoroethylene (PTFE) binder is controlled by adjusting the processing temperature during the fibrillization process, which enables uniform distribution of PTFE binder and carbon black (CB). Second, pore size/distribution and conducting network are engineered by multi‐dimensional conducting agents, enhancing Li‐ions and electrons transport in the electrode. Finally, the structural integrity of LiNi0.80Co0.15Al0.05O2 (NCA) particles is improved without fractures, which enables uniform pore distribution in the electrode by controlling the calendering step. The prepared 10 mAh cm−2 dry electrode with homogeneous microstructure shows reduced Rion and Rct due to short diffusion lengths, which improves electrochemical performances in LIBs with a high volumetric energy density of ≈710 Wh L−1. [ABSTRACT FROM AUTHOR]

Published
2024
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41. Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation

Author

Lee, Kyu-Tae, Yao, Yuan, He, Junwen, Fisher, Brent, Sheng, Xing, Lumb, Matthew, Xu, Lu, Anderson, Mikayla A., Scheiman, David, Han, Seungyong, Kang, Yongseon, Gumus, Abdurrahman, Bahabry, Rabab R., Lee, Jung Woo, Paik, Ungyu, Bronstein, Noah D., Alivisatos, A. Paul, Meitl, Matthew, Burroughs, Scott, Hussain, Muhammad Mustafa, Lee, Jeong Chul, Nuzzo, Ralph G., and Rogers, John A.

Published
2016

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