Nanoscale Investigation of Nb-Doped CaCu3Ti4O12 Grains

2011 ◽  
Vol 364 ◽  
pp. 455-459 ◽  
Author(s):  
Muhammad Azwadi Sulaiman ◽  
Sabar Derita Hutagalung ◽  
Zainal Arifin Ahmad
Keyword(s):  
Domain Boundary ◽  
Domain Size ◽  
Solid State Reaction Method ◽  
Sem Images ◽  
Force Microscopy ◽  
Atomic Force ◽  
Device Applications ◽  
Nanoscale Imaging ◽  
High Dielectric ◽  
Sem Analyses

CaCu3Ti4O12 (CCTO) is a promising material for microelectronic and microwave device applications due to its unique properties that posses high dielectric constant in the wide temperature range. In this work, atomic force microscopy (AFM) and scanning electron microscopy (SEM) analyses were applied for nanoscale imaging of Nb-doped CCTO grains. The Nb-doped CCTO pellets (CaCu3Ti4-xNbxO12+x/2; x = 0, 0.01, 0.03, 0.05, 0.1) were prepared via solid state reaction method and thermally etched at 940°C for an hour. From AFM and SEM images found that tiny bumped as well as terrace type domains are distributed within a grain. The domain size is ranging from 20 to 180 nm measured by AFM. The existence of domains on grain will produce grain boundary and domain boundary resistance inside CCTO. Both domain and grain resistance are believed to strongly influence the electrical properties of CCTO.

scholarly journals Multiple regimes of operation in bimodal AFM: understanding the energy of cantilever eigenmodes

2013 ◽  
Vol 4 ◽  
pp. 385-393 ◽  
Author(s):  
Daniel Kiracofe ◽  
Arvind Raman ◽  
Dalia Yablon
Keyword(s):  
Single Frequency ◽  
Force Microscopy ◽  
Atomic Force ◽  
Afm Imaging ◽  
Multiple Regimes ◽  
Nanoscale Imaging ◽  
Relative Kinetic ◽  
Series Of Experiments ◽  
Tapping Mode Afm ◽  
Afm Cantilever

One of the key goals in atomic force microscopy (AFM) imaging is to enhance material property contrast with high resolution. Bimodal AFM, where two eigenmodes are simultaneously excited, confers significant advantages over conventional single-frequency tapping mode AFM due to its ability to provide contrast between regions with different material properties under gentle imaging conditions. Bimodal AFM traditionally uses the first two eigenmodes of the AFM cantilever. In this work, the authors explore the use of higher eigenmodes in bimodal AFM (e.g., exciting the first and fourth eigenmodes). It is found that such operation leads to interesting contrast reversals compared to traditional bimodal AFM. A series of experiments and numerical simulations shows that the primary cause of the contrast reversals is not the choice of eigenmode itself (e.g., second versus fourth), but rather the relative kinetic energy between the higher eigenmode and the first eigenmode. This leads to the identification of three distinct imaging regimes in bimodal AFM. This result, which is applicable even to traditional bimodal AFM, should allow researchers to choose cantilever and operating parameters in a more rational manner in order to optimize resolution and contrast during nanoscale imaging of materials.

scholarly journals Estimating Step Heights from Top-Down SEM Images

2019 ◽  
Vol 25 (4) ◽  
pp. 903-911 ◽  
Author(s):  
Kerim Tugrul Arat ◽  
Jens Bolten ◽  
Aernout Christiaan Zonnevylle ◽  
Pieter Kruit ◽  
Cornelis Wouter Hagen
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Semiconductor Industry ◽  
Step Edge ◽  
Step Height ◽  
Top Down ◽  
Sem Images ◽  
Force Microscopy ◽  
Atomic Force ◽  
Primary Electrons

AbstractScanning electron microscopy (SEM) is one of the most common inspection methods in the semiconductor industry and in research labs. To extract the height of structures using SEM images, various techniques have been used, such as tilting a sample, or modifying the SEM tool with extra sources and/or detectors. However, none of these techniques focused on extraction of height information directly from top-down images. In this work, using Monte Carlo simulations, we studied the relation between step height and the emission of secondary electrons (SEs) resulting from exposure with primary electrons at different energies. It is found that part of the SE signal, when scanning over a step edge, is determined by the step height rather than the geometry of the step edge. We present a way to quantify this, arriving at a method to determine the height of structures from top-down SEM images. The method is demonstrated on three different samples using two different SEM tools, and atomic force microscopy is used to measure the step height of the samples. The results obtained are in qualitative agreement with the results from the Monte Carlo simulations.

scholarly journals The effect of moiré superstructures on topological edge states in twisted bismuthene homojunctions

2020 ◽  
Vol 6 (23) ◽  
pp. eaba2773 ◽  
Author(s):  
Jian Gou ◽  
Longjuan Kong ◽  
Xiaoyue He ◽  
Yu Li Huang ◽  
Jiatao Sun ◽  
...  
Keyword(s):  
Single Layer ◽  
Scanning Tunneling ◽  
Edge States ◽  
First Principles Calculations ◽  
Tunneling Microscopy ◽  
Force Microscopy ◽  
Atomic Force ◽  
Spatially Distributed ◽  
Topological States ◽  
Device Applications

Creating and controlling the topological properties of two-dimensional topological insulators is essential for spintronic device applications. Here, we report the successful growth of bismuth homostructure consisting of monolayer bismuthene and single-layer black phosphorus–like Bi (BP-Bi) on the HOPG surface. Combining scanning tunneling microscopy/spectroscopy with noncontact atomic force microscopy, moiré superstructures with twist angles in the bismuth homostructure and the modulation of topological edge states of bismuthene were observed and studied. First-principles calculations reproduced the moiré superlattice and indicated that the structure fluctuation is ascribed to the stacking modes between bismuthene and BP-Bi, which induce spatially distributed interface interactions in the bismuth homostructure. The modulation of topological edge states is directly related to the variation of interlayer interactions. Our results suggest a promising pathway to tailor the topological states through interfacial interactions.

scholarly journals Different directional energy dissipation of heterogeneous polymers in bimodal atomic force microscopy

RSC Advances ◽  
2019 ◽  
Vol 9 (47) ◽  
pp. 27464-27474 ◽  
Author(s):  
Xinfeng Tan ◽  
Dan Guo ◽  
Jianbin Luo
Keyword(s):  
Atomic Force Microscopy ◽  
Energy Dissipation ◽  
Dynamic Force ◽  
Force Detection ◽  
Force Microscopy ◽  
Nanomechanical Properties ◽  
Powerful Technique ◽  
Atomic Force ◽  
Nanoscale Imaging ◽  
Heterogeneous Polymers

Dynamic force microscopy (DFM) has become a multifunctional and powerful technique for the study of the micro–nanoscale imaging and force detection, especially in the compositional and nanomechanical properties of polymers.

Structural and mechanical properties of tantalum thin films ected by nitrogen ion implantation

2020 ◽  
Vol 34 (15) ◽  
pp. 2050163 ◽  
Author(s):  
A. H. Ramezani ◽  
S. Hoseinzadeh ◽  
Zh. Ebrahiminejad
Keyword(s):  
Friction Coefficient ◽  
Wear Mechanism ◽  
Mechanism Study ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Force Microscopy ◽  
Atomic Force ◽  
Coefficient Measurement ◽  
Nitrogen Ions ◽  
Nitrogen Ion

Tantalum bulk were implanted with nitrogen ions at different dose of [Formula: see text] ions/cm2 to [Formula: see text] ions/cm2 and at a energy 30 keV. The implanted samples were characterized using X-ray diffraction (XRD), atomic force microscopy (AFM), microhardness testing, friction coefficient measurements and wear mechanism study. Scanning electron microscopy (SEM) images were used to analyze the friction of samples. The XRD results confirmed that the increasing dose affects the formation of the TaN phase. Based on AFM images, the morphology and surface roughness change proportionally to grain size after implantation. It was found that hardness increases as energy increases. From the friction coefficient measurement, this coefficient decreases as energy increases. For the un-implanted sample, the wear mechanism has abrasion, and with increasing the energy, it shifts to being flake and sticky.

Nanoscale imaging of microbial pathogens using atomic force microscopy

2009 ◽  
Vol 1 (2) ◽  
pp. 168-180 ◽  
Author(s):  
David Alsteens ◽  
Etienne Dague ◽  
Claire Verbelen ◽  
Guillaume Andre ◽  
Vincent Dupres ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Microbial Pathogens ◽  
Force Microscopy ◽  
Atomic Force ◽  
Nanoscale Imaging

Optical and Structural Properties of Fluorine Doped SnO2 on Si (100) for Photovoltaic Application

2018 ◽  
Vol 13 (10) ◽  
pp. 1522-1532 ◽  
Author(s):  
S. Nivetha ◽  
K. Kaviyarasu ◽  
A. Ayeshamariam ◽  
N. Punithavelan ◽  
R. Perumalsamy ◽  
...  
Keyword(s):  
Spray Pyrolysis Technique ◽  
Energy Difference ◽  
Vital Role ◽  
X Ray Diffraction ◽  
Energy Storage Devices ◽  
Sem Images ◽  
Storage Devices ◽  
Force Microscopy ◽  
Photovoltaic Application ◽  
Atomic Force

Photovoltaic material plays a vital role in the production of energy storage devices, more specifically in solar cell fabrications. In this work, ITO:F-doped materials were coated over the silicon substrate through spray pyrolysis technique. X-ray diffraction studies were conducted for porous silicon (PSi) coated with ITO:F structures formed at different current densities. This pore formation is evident from the broad peak at 69.9°, revealing an amorphous-like nature but at the same location where the single crystalline peak also is observed. These pores are explicitly shown in the SEM images in which very fine surface fragments are observed. At 20 mA/cm2, well-defined porous patterns that were uniformly distributed over the surface were observed. The microstructures observed via atomic force microscopy for these PSi coated with ITO:F structures are randomly aligned and almost evenly distributed over the entire surface of these nanorods, which are approximately 40 nm. Radiative recombination of electrons from a level in the conduction band or its subband to a level at an energy difference of greater than 1.7 eV in the valance band or its subband will emit visible light.

scholarly journals Self-Assembly of Rice Bran Globulin Fibrils in Electrostatic Screening: Nanostructure and Gels

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Lihua Huang ◽  
Yehui Zhang ◽  
Haibin Li
Keyword(s):  
Ionic Strength ◽  
Rice Bran ◽  
Self Assembly ◽  
Gel Properties ◽  
Sem Images ◽  
Force Microscopy ◽  
Atomic Force ◽  
Repulsive Forces ◽  
Low Ionic Strength ◽  
Kinetics Of

The effects of various ionic strengths and protein concentrations on the fibrils structure and gel properties of rice bran globulin (RBG) at pH 2.0 were investigated using atomic force microscopy (AFM), rheometer, and scanning electron microscope (SEM). AFM images showed the morphology of assembling RBG fibrils from strand beads to becoming branch clustered, when electrostatic repulsive forces attenuated gradually with increasing ionic strength. NaCl seems to accelerate the kinetics of fibrils formation, resulting in a significant increase in Th T fluorescence intensity. The increased ionic strengths promote particle size increasing and zeta potential decreasing synchronously. The percolation modelG'~C-Cpnbe used to calculate theoretical RBG gels concentration at various ionic strengths (0–500 mM), which decreased from 15.17 ± 0.63 to 2.26 ± 0.27 wt%. SEM images exhibited a granular mesh-like gel structure. A more homogenous structure occurred in low ionic strength. This study elucidates properties of RBG fibrils and gels as a bioactive material.

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