Fabrication of 3D metal dot arrays by geometrically structured dynamic shadowing lithography.

Langmuir

Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States.

Published: November 2011

Sphere lithography (SL), sometimes erroneously generalized as nanosphere lithography (NSL), stands out as a versatile technique capable of producing 2D periodic micro- and nanostructures with general materials applicability, flexible size and shape control, high throughput, and elegance of simplicity. Many of the fundamental aspects of the features produced by SL have been investigated in a systematic manner, including the optical, magnetic, electronic, and catalytic behaviors with emphasis toward applications in biosensing, ultrasensitive spectroscopy, and nanodevice fabrication. Previous work has primarily focused on two-dimensional patterning, however, with little attention paid to vertical growth of the SL features. In this work, the 3D structural evolution of metal dot arrays at two different length scales was demonstrated by SL-based geometrically structured dynamic shadowing lithography (GSDSL). An empirically derived model of structural growth is also developed to predict the shape and size of the features in this system.

Download full-text PDF

Source
http://dx.doi.org/10.1021/la2027785DOI Listing

Publication Analysis

Top Keywords

metal dot
8
dot arrays
8
geometrically structured
8
structured dynamic
8
dynamic shadowing
8
shadowing lithography
8
fabrication metal
4
arrays geometrically
4
lithography
4
lithography sphere
4

Similar Publications

Supercycle Al-Doped ZnMgO Alloys via Atomic Layer Deposition for Quantum Dot Light-Emitting Diodes.

ACS Appl Mater Interfaces

January 2025

Department of Photonics and Nanoelectronics, and BK21 FOUR ERICA-ACE Center, Hanyang University, Ansan 15588, Korea.

Colloidal quantum-dot light-emitting diodes (QD-LEDs) have been significantly improved in terms of device performance and lifetime by employing zinc oxide (ZnO) as an electron transport layer (ETL). Although atomic layer deposition (ALD) allows fabrication of uniform, high-quality ZnO films with minimal defects, the high conductivity of ZnO has hindered its straightforward application as an ETL in QD-LEDs. Herein, we propose fabrication of Al-doped ZnMgO (Al:ZnMgO) ETLs for QD-LEDs through a supercycle ALD, with alternating depositions of various metal oxides.

View Article and Find Full Text PDF

Motivated by the importance of Hg detection in water due to its harmful effect on the environment and human health, we investigated a recently developed nanocomposite based on carbon dots (CDs) and LAPONITE as an optical chemical sensor using photoluminescence emission. While several studies have reported the Hg detection using CDs' photoluminescence emission, there is a lack of in-depth investigation into the quenching mechanisms involved in turn-off sensors. In this study, we propose a Stern-Volmer analysis at three different temperatures (288, 298, and 303 K).

View Article and Find Full Text PDF

We demonstrate the use of [2-(9-carbazol-9-yl)ethyl]phosphonic acid (2PACz) and [2-(3,6-di--butyl-9-carbazol-9-yl)ethyl]phosphonic acid (-Bu-2PACz) as anode modification layers in metal-halide perovskite quantum dot light-emitting diodes (QLEDs). Compared to conventional QLED structures with PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrenesulfonate)/PVK (poly(9-vinylcarbazole)) hole-transport layers, the QLEDs made with phosphonic acid (PA)-modified indium tin oxide (ITO) anodes show an over seven-fold increase in brightness, achieving a brightness of 373,000 cd m, one of the highest brightnesses reported to date for colloidal perovskite QLEDs. Importantly, the onset of efficiency roll-off, or efficiency droop, occurs at ∼1000-fold higher current density for QLEDs made with PA-modified anodes compared to control QLEDs made with conventional PEDOT:PSS/PVK hole transport layers, allowing the devices to sustain significantly higher levels of external quantum efficiency at a brightness of >10 cd m.

View Article and Find Full Text PDF

Temperature-sensitive driving assembled fluorescence hydrogel based dual-mode sensor for adsorbing and detecting of heavy metal cadmium ions in food and water.

Food Chem

December 2024

State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Quality and Health of Tianjin, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China.

The denatured bovine serum albumin (dBSA) is coupled with the CdTe/CdS quantum dot and the resulting CdTe/CdS@dBSA complex is assembled and retained in the poly(n-isopropyl acrylamide) (PNIPAM) hydrogel via regulating temperature and pH to form the CdTe/CdS@dBSA-PNIPAM fluorescence hydrogel substrate, which is able to adsorb and sense cadmium ions (Cd). Based on this fluorescence hydrogel, a fluorescence and colorimetric dual-mode detection system is established to quantitatively detect Cd with a limit of detection (LOD) of 2.88 nM for fluorescence detection and 11.

View Article and Find Full Text PDF

For moiré bilayer TMD superlattices, full-configuration-interaction (FCI) calculations are presented that take into account both the intra-moiré-quantum-dot (MQD) charge-carrier Coulombic interactions, as well as the crystal-field effect from the surrounding moiré pockets (inter-moiré-QD interactions). The effective computational embedding strategy introduced here allows for an FCI methodogy that enables the complete interpretation of the counterintuitive experimental observations reported recently in the context of moiré TMD superlattices at integer fillings ν=2 and 4. Two novel states of matter are reported: (i) a genuinely quantum-mechanical supercrystal of sliding Wigner molecules (WMs) for unstrained moiré TMD materials (when the crystal field is commensurate with the trilobal symmetry of the confining potential in each embedded MQD) and (ii) a supercrystal of pinned Wigner molecules when the crystal field is incommensurate with the trilobal symmetry or straining of the whole material is involved.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!