scholarly journals Study on the Physical Properties of a SiNW Biosensor to the Sensitivity of DNA Detection

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5716
Author(s):  
Siti Noorhaniah Yusoh ◽  
Khatijah Aisha Yaacob
Keyword(s):  
Surface Roughness ◽  
Physical Properties ◽  
Limit Of Detection ◽  
Silicon Nanowire ◽  
Volume Ratio ◽  
Silicon Nanowire Arrays ◽  
Atomic Force ◽  
Local Anodic Oxidation ◽  
Wet Chemical ◽  
Biosensor Device

SiNW (silicon nanowire) arrays consisting of 5- and 10-wires were fabricated by using an atomic force microscope—the local anodic oxidation (AFM-LAO) technique followed by wet chemical etching. Tetramethylammonium hydroxide (TMAH) and isopropyl alcohol (IPA) at various concentrations were used to etch SiNWs. The SiNWs produced were differed in dimension and surface roughness. The SiNWs were functionalized and used for the detection of deoxyribonucleic acid (DNA) dengue (DEN-1). SiNW-based biosensors show sensitive detection of dengue DNA due to certain factors. The physical properties of SiNWs, such as the number of wires, the dimensions of wires, and surface roughness, were found to influence the sensitivity of the biosensor device. The SiNW biosensor device with 10 wires, a larger surface-to-volume ratio, and a rough surface is the most sensitive device, with a 1.93 fM limit of detection (LOD).

SILICON NANOWIRE TRANSISTOR FABRICATED BY AFM NANOLITHOGRAPHY FOLLOWED BY WET CHEMICAL ETCHING PROCESS

2010 ◽  
Vol 09 (04) ◽  
pp. 289-293 ◽  
Author(s):  
K. C. LEW ◽  
SABAR D. HUTAGALUNG
Keyword(s):  
Chemical Etching ◽  
Oxidation Process ◽  
Silicon Nanowire ◽  
Silicon Layer ◽  
Silicon On Insulator ◽  
Atomic Force ◽  
Nanowire Transistor ◽  
Local Anodic Oxidation ◽  
Wet Chemical ◽  
Anodic Oxidation Process

Atomic force microscope (AFM) nanolithography was performed to create nanowire transistor pattern via local anodic oxidation process on surface of silicon-on-insulator (SOI) wafer. This nanoscale oxide pattern is used as a mask system for chemical etching to produce silicon nanowire transistor. The device with component structures of a silicon nanowire (SiNW) as channel with source, drain, and gate pads had been drawn at 9 V tip voltage, 6 μm/s writing speed with humidity 55.8–68.9%RH. The designed device was etched with tetramethylammonium hydroxide (TMAH) to remove uncovered silicon layer but oxide pattern remains. In order to obtain SiNW transistor, sample was etched using hydrogen fluoride (HF) to remove oxide layer. From the AFM and field emission scanning electron microscope (FESEM) observation found that the SiNW transistor with wire size of 92.65 nm in wire thickness, 90.83 nm wire width and 10.30 μm in length with contact pads size of about 5 μ m × 5 μ m has been successfully fabricated.

Fractal analysis with scanning probe microscopy

1992 ◽  
Vol 50 (2) ◽  
pp. 1046-1047
Author(s):  
Paul E. West ◽  
Sid Marchesse-Rugona ◽  
Zhuoning Li
Keyword(s):  
Surface Roughness ◽  
Fractal Dimension ◽  
Physical Properties ◽  
Fractal Analysis ◽  
Three Dimensional ◽  
Optical Microscope ◽  
Two Dimensional ◽  
Atomic Force ◽  
Dimensional Measurements ◽  
Surface Profiles

Surface roughness determined qualitatively by direct visualization can be correlated to several physical properties. However, finding a suitable method of quantifying surface roughness, until recently, has been difficult. The concept of Fractal Dimension, recently popularized by Mandelbrot(1982) has been extremely successful in quantifying surface roughness and relating it to such measurable physical properties such as; cleanability, catalytic activity, rate of corrosion, and even flavor.Atomic Force Microscopes permit direct three dimensional measurements of surface microstructure. AFM images are obtained by measuring the motion of a sharp stylus as it is scanned across a surface. Because the AFM directly measures three dimensional topograms, it is ideally suited for two dimensional and three dimensional fractal analysis. Other microscope techniques such as the scanning electron or optical microscope give only two dimensional magnification and fractal measurements are not easily made.The Atomic Force Microscope enables us to obtain the fractal dimension of surface profiles as well as surface areas. For surface profiles we use a box counting method (Mandelbrot 1986, Chesters et al. 1989).

Fabrication and Properties of Large-Area Silicon Nanowire Arrays

2009 ◽  
Vol 610-613 ◽  
pp. 604-609
Author(s):  
Hui Fang ◽  
Yin Wu ◽  
Jing Zhu
Keyword(s):  
Silicon Nanowire ◽  
Optical Devices ◽  
Nanowire Arrays ◽  
Photoluminescence Spectra ◽  
Large Area ◽  
Silicon Nanowire Arrays ◽  
Potential Applications ◽  
Wet Chemical ◽  
Wet Chemical Etching ◽  
20 Nm

Wet chemical etching with dry metal deposition method has been developed to fabricate large-area aligned silicon nanowire (SiNW) arrays. The combination of nanoclusters Ag film with proper interconnection and interspaces (of about 20 nm thick), and proper temperature during etching (from 20 to 80 °C) is vital to successfully fabricating large-area uniform SiNW arrays. Raman and photoluminescence spectra of the SiNW arrays indicated their potential applications in chemical detection and optical devices ,respectively.

Chemical Wet Etching of Silicon Wafers from a Mixture of Concentrated Acids

2011 ◽  
Vol 264-265 ◽  
pp. 1027-1032 ◽  
Author(s):  
M.R. Ismail ◽  
Wan Jeffrey Basirun
Keyword(s):  
Surface Roughness ◽  
Surface Condition ◽  
Surface Damage ◽  
Wet Etching ◽  
Tem Analysis ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Wet Chemical ◽  
Thinning Process

Warpage on the backside of silicon wafer after thinning process is examined. The thinning process includes back-grinding (BG) and wet chemical etching (WCE). Results of wafer warpage were compared to sub-surface damage from Transmission Electron Microscopy (TEM) analysis and showed that sub-surface damage on the backside of the silicon 100 would induce high wafer warpage, and reduced wafer strength. Further studies from surface roughness and topography of each surface finish is obtained by Atomic Force Microscopy (AFM) and SEM show that low surface roughness is in accordance with smooth surface condition, which comes after the wet etching process.

Local Anodic Oxidation of Phosporous-Implanted 4H-SiC by Atomic Force Microscopy

2012 ◽  
Vol 717-720 ◽  
pp. 905-908 ◽  
Author(s):  
Jung Ho Lee ◽  
Jung Jun Ahn ◽  
Anders Hallén ◽  
Carl Mikael Zetterling ◽  
Sang Mo Koo
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Oxidation Behavior ◽  
Annealing Process ◽  
Applied Bias ◽  
Force Microscopy ◽  
Atomic Force ◽  
Local Oxidation ◽  
Local Anodic Oxidation ◽  
Post Implantation

In this work, local oxidation behavior in phosphorous ion-implanted 4H-SiC has been investigated by using atomic force microscopy (AFM). The AFM-local oxidation (LO) has been performed on the implanted samples, with and without activation anneal, using varying applied bias (15/20/25 V). It has been clearly shown that the post-implantation annealing process at 1650 oC has a great impact on the local oxidation rate by electrically activating the dopants and by modulating the surface roughness. In addition, the composition of resulting oxides changes depending on the doping level of SiC surfaces.

Wet-Chemical Etching of Ruthenium in Acidic Ce4+ Solution

2018 ◽  
Vol 282 ◽  
pp. 284-287
Author(s):  
Harold Philipsen ◽  
Sander Teck ◽  
Nils Mouwen ◽  
Wouter Monnens ◽  
Quoc Toan Le
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Chemical Etching ◽  
Rutherford Backscattering ◽  
Force Microscopy ◽  
Acidic Solutions ◽  
Atomic Force ◽  
Wet Chemical ◽  
Wet Chemical Etching ◽  
Low K

The wet-chemical etching of ruthenium in acidic solutions of cerium (IV) has been investigated using electrochemical methods. Etch rates were determined using Rutherford backscattering spectroscopy (RBS) and post-etching surface roughness was investigated using atomic force microscopy (AFM). Low-k material is compatible with the etchant, however, residues were formed.

Surface roughness measurements of vanadium-contaminated fluidized cracking catalysts by atomic force microscopy

1996 ◽  
Vol 54 ◽  
pp. 866-867
Author(s):  
H. Kinney ◽  
M.L. Occelli ◽  
S.A.C. Gould
Keyword(s):  
Surface Roughness ◽  
Zeolite Y ◽  
Atomic Level ◽  
Microporous Structure ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
Roughness Measurements ◽  
Cracking Catalysts

For this study we have used a contact mode atomic force microscope (AFM) to study to topography of fluidized cracking catalysts (FCC), before and after contamination with 5% vanadium. We selected the AFM because of its ability to well characterize the surface roughness of materials down to the atomic level. It is believed that the cracking in the FCCs occurs mainly on the catalysts top 10-15 μm suggesting that the surface corrugation could play a key role in the FCCs microactivity properties. To test this hypothesis, we chose vanadium as a contaminate because this metal is capable of irreversibly destroying the FCC crystallinity as well as it microporous structure. In addition, we wanted to examine the extent to which steaming affects the vanadium contaminated FCC. Using the AFM, we measured the surface roughness of FCCs, before and after contamination and after steaming.We obtained our FCC (GRZ-1) from Davison. The FCC is generated so that it contains and estimated 35% rare earth exchaged zeolite Y, 50% kaolin and 15% binder.

In Operando Detection of the Physical Properties Change of the Interfacial Electrolyte during Li-Metal Electrode Reaction by Atomic Force Microscopy

2020 ◽  
Author(s):  
Mitsunori Kitta
Keyword(s):  
Atomic Force Microscopy ◽  
Energy Dissipation ◽  
Physical Properties ◽  
Electrode Surface ◽  
Electrode Reaction ◽  
Metal Electrode ◽  
Ion Concentration ◽  
Force Microscopy ◽  
Atomic Force ◽  
Discharge Reaction

This manuscript propose the operando detection technique of the physical properties change of electrolyte during Li-metal battery operation.The physical properties of electrolyte solution such as viscosity (η) and mass densities (ρ) highly affect the feature of electrochemical Li-metal deposition on the Li-metal electrode surface. Therefore, the operando technique for detection these properties change near the electrode surface is highly needed to investigate the true reaction of Li-metal electrode. Here, this study proved that one of the atomic force microscopy based analysis, energy dissipation analysis of cantilever during force curve motion, was really promising for the direct investigation of that. The solution drag of electrolyte, which is controlled by the physical properties, is directly concern the energy dissipation of cantilever motion. In the experiment, increasing the energy dissipation was really observed during the Li-metal dissolution (discharge) reaction, understanding as the increment of η and ρ of electrolyte via increasing of Li-ion concentration. Further, the dissipation energy change was well synchronized to the charge-discharge reaction of Li-metal electrode.This study is the first report for direct observation of the physical properties change of electrolyte on Li-metal electrode reaction, and proposed technique should be widely interesting to the basic interfacial electrochemistry, fundamental researches of solid-liquid interface, as well as the battery researches.

Brittle Behaviour in Aspirin Crystals: Evidence of Spalling Fracture

2020 ◽  
Author(s):  
Benjamin P. A. Gabriele ◽  
Craig J. Williams ◽  
Douglas Stauffer ◽  
Brian Derby ◽  
Aurora J. Cruz-Cabeza
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Single Crystals ◽  
Spalling Fracture ◽  
Force Microscopy ◽  
Atomic Force ◽  
Afm Imaging

<div> <div> <div> <p>Single crystals of aspirin form I were cleaved and indented on their dominant face. Upon inspection, it was possible to observe strongly anisotropic shallow lateral cracks due to the extreme low surface roughness after cleavage. Atomic Force Microscopy (AFM) imaging showed spalling fractures nucleating from the indent corners, forming terraces with a height of one or two interplanar spacings d100. The formation of such spalling fractures in aspirin was rationalised using basic calculations of attachment energies, showing how (100) layers are poorly bonded when compared to their relatively higher intralayer bonding. An attempt at explaining the preferential propagation of these fractures along the [010] direction is discussed. </p> </div> </div> </div>

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