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991.
Jaehyun Moon Joohyun Hwang Jin Woo Huh Jin-Wook Shin Doo-Hee Cho Seung Koo Park Jun-Han Han Chul Woong Joo Jeong-Ik Lee Hye Yong Chu 《Materials Research Bulletin》2012,47(10):2788-2791
A linear stability model was formulated to analyze the perturbation of solid polymer surfaces. Surface energy and thermal stress were considered as the main variables. The surface tends to more unstable as the temperature increase. This is interpreted as the dominancy of the lattice vacancy diffusion over surface mass diffusion and the increase in thermal stress. 相似文献
992.
Photo‐Stable Organic Thin‐Film Transistor Utilizing a New Indolocarbazole Derivative for Image Pixel and Logic Applications 下载免费PDF全文
Ji Hoon Park Hee Sung Lee Soohyung Park Sung‐Wook Min Yeonjin Yi Cheon‐Gyu Cho Jiwon Han Tae Woong Kim Seongil Im 《Advanced functional materials》2014,24(8):1109-1116
Small molecule pentacene layer has been a representative among many organic thin‐film transistor (OTFT) channels with decent p‐type mobilities, but it is certainly light‐sensitive due to its relatively small highest occupied molecular orbital‐lowest unoccupied molecular orbital (HOMO‐LUMO) gap (1.85 eV). Although a few other small molecule‐based layers have been reported later, their photo‐stabilities or related device applications have hardly been addressed. Here, a new photostable organic layer is reported, heptazole (C26H16N2), which has almost the same HOMO level as that of pentacene but with a higher HOMO‐LUMO gap (≈2.95 eV). This heptazole OTFT displays a decent mobility comparable to that of conventional amorphous Si TFTs, showing good photostability unlike pentacene OTFTs. An image pixel driving the photostable heptazole OTFT connected to a pentacene/Al Schottky photodiode is demonstrated. This heptazole OTFT also conveniently forms a logic inverter coupled with a pentacene OTFT, sharing Au for source/drain. 相似文献
993.
A Review of Three‐Dimensional Resistive Switching Cross‐Bar Array Memories from the Integration and Materials Property Points of View 下载免费PDF全文
Jun Yeong Seok Seul Ji Song Jung Ho Yoon Kyung Jean Yoon Tae Hyung Park Dae Eun Kwon Hyungkwang Lim Gun Hwan Kim Doo Seok Jeong Cheol Seong Hwang 《Advanced functional materials》2014,24(34):5316-5339
Issues in the circuitry, integration, and material properties of the two‐dimensional (2D) and three‐dimensional (3D) crossbar array (CBA)‐type resistance switching memories are described. Two important quantitative guidelines for the memory integration are provided with respect to the required numbers of signal wires and sneak current paths. The advantage of 3D CBAs over 2D CBAs (i.e., the decrease in effect memory cell size) can be exploited only under certain limited conditions due to the increased area and layout complexity of the periphery circuits. The sneak current problem can be mitigated by the adoption of different voltage application schemes and various selection devices. These have critical correlations, however, and depend on the involved types of resistance switching memory. The problem is quantitatively dealt with using the generalized equation for the overall resistance of the parasitic current paths. Atomic layer deposition is discussed in detail as the most feasible fabrication process of 3D CBAs because it can provide the device with the necessary conformality and atomic‐level accuracy in thickness control. Other subsidiary issues related to the line resistance, maximum available current, and fabrication technologies are also reviewed. Finally, a summary and outlook on various other applications of 3D CBAs are provided. 相似文献
994.
Optical Waveguiding: Remote Biosensing with Polychromatic Optical Waveguide Using Blue Light‐Emitting Organic Nanowires Hybridized with Quantum Dots (Adv. Funct. Mater. 24/2014) 下载免费PDF全文
995.
Marc-Joseph Antonini Atharva Sahasrabudhe Anthony Tabet Miriam Schwalm Dekel Rosenfeld Indie Garwood Jimin Park Gabriel Loke Tural Khudiyev Mehmet Kanik Nathan Corbin Andres Canales Alan Jasanoff Yoel Fink Polina Anikeeva 《Advanced functional materials》2021,31(43):2104857
Fiber drawing enables scalable fabrication of multifunctional flexible fibers that integrate electrical, optical, and microfluidic modalities to record and modulate neural activity. Constraints on thermomechanical properties of materials, however, have prevented integrated drawing of metal electrodes with low-loss polymer waveguides for concurrent electrical recording and optical neuromodulation. Here, two fabrication approaches are introduced: 1) an iterative thermal drawing with a soft, low melting temperature (Tm) metal indium, and 2) a metal convergence drawing with traditionally non-drawable high Tm metal tungsten. Both approaches deliver multifunctional flexible neural interfaces with low-impedance metallic electrodes and low-loss waveguides, capable of recording optically-evoked and spontaneous neural activity in mice over several weeks. These fibers are coupled with a light-weight mechanical microdrive (1 g) that enables depth-specific interrogation of neural circuits in mice following chronic implantation. Finally, the compatibility of these fibers with magnetic resonance imaging is demonstrated and they are applied to visualize the delivery of chemical payloads through the integrated channels in real time. Together, these advances expand the domains of application of the fiber-based neural probes in neuroscience and neuroengineering. 相似文献
996.
Ik Seon Kwon Tekalign Terfa Debela In Hye Kwak Yun Chang Park Jaemin Seo Ju Yong Shim Seung Jo Yoo Jin‐Gyu Kim Jeunghee Park Hong Seok Kang 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(13)
2D MoS2 nanostructures have recently attracted considerable attention because of their outstanding electrocatalytic properties. The synthesis of unique Co–Ru–MoS2 hybrid nanosheets with excellent catalytic activity toward overall water splitting in alkaline solution is reported. 1T′ phase MoS2 nanosheets are doped homogeneously with Co atoms and decorated with Ru nanoparticles. The catalytic performance of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is characterized by low overpotentials of 52 and 308 mV at 10 mA cm?2 and Tafel slopes of 55 and 50 mV decade?1 in 1.0 m KOH, respectively. Analysis of X‐ray photoelectron and absorption spectra of the catalysts show that the MoS2 well retained its metallic 1T′ phase, which guarantees good electrical conductivity during the reaction. The Gibbs free energy calculation for the reaction pathway in alkaline electrolyte confirms that the Ru nanoparticles on the Co‐doped MoS2 greatly enhance the HER activity. Water adsorption and dissociation take place favorably on the Ru, and the doped Co further catalyzes HER by making the reaction intermediates more favorable. The high OER performance is attributed to the catalytically active RuO2 nanoparticles that are produced via oxidation of Ru nanoparticles. 相似文献
997.
Raman Scattering Mapping: Sensitive and Reproducible Immunoassay of Multiple Mycotoxins Using Surface‐Enhanced Raman Scattering Mapping on 3D Plasmonic Nanopillar Arrays (Small 39/2018) 下载免费PDF全文
998.
999.
Mansu Kim Nam-Ki Min Alexander Efremov Hyun Woo Lee Chi-Sun Park Kwang-Ho Kwon 《Journal of Materials Science: Materials in Electronics》2008,19(10):957-964
The analysis of the Er-doped silica glass films (62%SiO2–30%B2O3–8%P2O5 + 0.2 wt%. Er2O3) etch mechanism in the CF4/O2 inductively coupled plasma was carried out using the combination of simplified models for plasma chemistry and etch kinetics.
As the O2 mixing ratio in the CF4/O2 plasma increases from 0% to 30%, the etch rate decreases monotonically in the range of 385–190 nm/min that contradicts with
the behavior of F atom density and flux. From the model-based analysis, it was found that, at low ion bombardment energies,
the etch process followed the formal kinetics of ion-assisted chemical reaction and was controlled by both neutral and ion
fluxes. 相似文献
1000.
Jong-Keuk Park 《Thin solid films》2008,516(11):3661-3664
This study investigated the effects of a nanoscale multi-layered structure on the hardness and thermal stability of Ti-Al-B-N coating. Bilayer period of nanoscale multi-layered TiAlN/BN coating, prepared by alternating deposition of TiAlN and BN layers, was controlled by changing BN target power. The hardness value of TiAlN coating increased through nanoscale multi-layered structurization with a thin (∼ 0.6 nm) BN phase. The intensity of low angle XRD peaks and hardness of the nanoscale multi-layered TiAlN/BN coatings increased after heat-treatment in an N2 atmosphere. The nanoscale multi-layered TiAlN/BN coating showed better thermal stability than that of TiAlN coating. 相似文献