Investigation of the Effect of Native Oxide Layer on Performance of Interdigitated Impedance-Based Silicon Biochemical Sensors

Volume 1: 14th International Conference on Micro- and Nanosystems (MNS) ◽

10.1115/detc2020-22207 ◽

2020 ◽

Author(s):

Nadia Ebrahimpour Tolouei ◽

Shima Ghamari ◽

Mohammad Shavezipur

Keyword(s):

Oxide Layer ◽

Double Layer ◽

Electrode Materials ◽

Low Frequency ◽

Native Oxide ◽

Native Oxide Layer ◽

Double Layer Capacitance ◽

Biochemical Sensors ◽

Electrode Surfaces ◽

In Series

Abstract Chemical and biological detection using Electrochemistry Impedance Spectroscopy (EIS) highly depends on the electrical characteristics of the electrodes used in the measurement process. In this work, the effect of surface coating on behavior of interdigitated impedance-based biochemical sensors is studied. Two interdigitated sensors with the same geometry and different electrode materials are fabricated using a standard process. One electrode is made of gold and the other electrode is made of polycrystalline silicon covered with a thin layer of native silicon dioxide. Different concentrations of di(2-ethylhexyl) phthalate (DEHP) in water are used and the Nyquist responses of the two sensors exposed to these solutions are obtained. The measurement results show that at high frequency both sensors form double-layer capacitance values on their electrode surfaces, however, the silicon sensor has a much lower double-layer capacitance values, because formation of oxide layer adds to the gap between charges at the interface of the electrode and the solution. Moreover, comparing the low frequency regions of the Nyquist plots for two sensors shows that the presence of oxide layer affects the Warburg effect and the charge diffusion near the surface of the electrode, creating an extra capacitive element in series with the diffusion effect. The results of this work may be extended to other interdigitated biochemical sensors that may have other sources of contamination on their surfaces.

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Wettability in pressure infiltration of SiC and oxidized SiC particle compacts by molten Al and Al-12wt%Si alloy

Journal of Materials Research ◽

10.1557/jmr.2007.0282 ◽

2007 ◽

Vol 22 (8) ◽

pp. 2273-2278 ◽

Cited By ~ 3

Author(s):

J.M. Molina ◽

J. Tian ◽

C. Garcia-Cordovilla ◽

E. Louis ◽

J. Narciso

Keyword(s):

Contact Angle ◽

Oxide Layer ◽

Low Temperatures ◽

Native Oxide ◽

Native Oxide Layer ◽

Threshold Pressure ◽

Pressure Infiltration ◽

Surface Conditions ◽

Infiltration Behavior ◽

Sic Particle

The infiltration behavior of compacts of SiC particles in two surface conditions, as-received and thermally oxidized, was investigated by using pure Al and Al-12wt%Si as infiltrating metals. Analysis of the threshold pressure for infiltration revealed that the process is governed by the same contact angle for all different systems, no matter the metal or particle condition. This leads to the conclusion that oxidation does not modify the wetting characteristics of the particles, most probably because they are already covered by a thin native oxide layer that remains unaltered in processing routes involving short contact times and low temperatures, such as actual conditions of pressure infiltration at 700 °C.

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The Effect of Surface States on Secondary Electron (SE) Dopant Contrast from Silicon p-n Junctions

MRS Proceedings ◽

10.1557/proc-1026-c04-02 ◽

2007 ◽

Vol 1026 ◽

Author(s):

Augustus K. W. Chee ◽

Conny Rodenburg ◽

Colin John Humphreys

Keyword(s):

Oxide Layer ◽

Computer Modelling ◽

Surface States ◽

Native Oxide ◽

Native Oxide Layer ◽

Element Analysis ◽

Surface Band ◽

Band Bending ◽

Wide Range ◽

Se Doping

AbstractDetailed computer modelling using finite-element analysis was performed for Si p-n junctions to investigate the effects of surface states and doping concentrations on surface band-bending, surface junction potentials and external patch fields. The density of surface states was determined for our Si specimens with a native oxide layer. Our calculations show that for a typical density of surface states for a Si specimen with a native oxide layer, the effects of external patch fields are negligible and the SE doping contrast is due to the built-in voltage across the p-n junction modified by surface band-bending. There is a good agreement between the experimental doping contrast and the calculated junction potential just below the surface, taking into account surface states, for a wide range of doping concentrations.

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Nano-Thick Amorphous Oxide Layer Produced by Plasma on Type 316L Stainless Steel for Improved Corrosion Resistance Under Plastic Deformation

CORROSION ◽

10.5006/2674 ◽

2018 ◽

Vol 74 (9) ◽

pp. 1011-1022 ◽

Cited By ~ 1

Author(s):

Megan Mahrokh Dorri ◽

Stéphane Turgeon ◽

Maxime Cloutier ◽

Pascale Chevallier ◽

Diego Mantovani

Keyword(s):

Plastic Deformation ◽

Stainless Steel ◽

Oxide Layer ◽

Electrochemical Impedance ◽

Open Circuit ◽

Localized Corrosion ◽

Native Oxide ◽

Native Oxide Layer ◽

Amorphous Oxide ◽

Amorphous Oxide Layer

Localized corrosion constitutes a major concern in medical devices made of stainless steel. The conventional approach to circumvent such a problem is to convert the surface polycrystalline microstructure of the native oxide layer to an amorphous oxide layer, a few micrometers thick. This process cannot, however, be used for devices such as stents that undergo plastic deformation during their implantation, especially those used in vascular surgery for the treatment of cardiac, neurological, and peripheral vessels. This work explores the feasibility of producing a nano-thick plastic-deformation resistant amorphous oxide layer by plasma-based surface modifications. By varying the plasma process parameters, oxide layers with different features were produced and their properties were investigated before and after clinically-relevant plastic deformation. These properties and the related corrosion mechanisms were mainly evaluated using the electrochemical methods of open-circuit potential, cyclic potentiodynamic polarization, and electrochemical impedance spectroscopy. Results showed that, under optimal conditions, the resistance to corrosion and to the permeation of ions in a phosphate buffered saline, even after deformation, was significantly enhanced.

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Nanoscale patterning of Si(100) surfaces by scratching through the native oxide layer using atomic force microscope

Applied Physics Letters ◽

10.1063/1.1404195 ◽

2001 ◽

Vol 79 (12) ◽

pp. 1882-1884 ◽

Cited By ~ 35

Author(s):

L. Santinacci ◽

T. Djenizian ◽

P. Schmuki

Keyword(s):

Atomic Force Microscope ◽

Oxide Layer ◽

Native Oxide ◽

Native Oxide Layer ◽

Nanoscale Patterning ◽

Atomic Force

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Эволюция физико-химических свойств поверхности GaSb(100) в растворах сульфида аммония

Физика и техника полупроводников ◽

10.21883/ftp.2019.07.47866.9070 ◽

2019 ◽

Vol 53 (7) ◽

pp. 908

Author(s):

М.В. Лебедев ◽

Т.В. Львова ◽

А.Л. Шахмин ◽

О.В. Рахимова ◽

П.А. Дементьев ◽

...

Keyword(s):

Oxide Layer ◽

Photoelectron Spectroscopy ◽

Treatment Time ◽

Solution Concentration ◽

Native Oxide ◽

Semiconductor Surface ◽

Native Oxide Layer ◽

Force Microscopy ◽

Fermi Level Pinning ◽

Ammonium Sulfide

AbstractVarious conditions of passivation of the GaSb(100) surface by ammonium sulfide ((NH_4)_2S) solutions depending on the solution concentration, solvent, and treatment time are investigated by X-ray photoelectron spectroscopy and atomic-force microscopy. It is shown that treatment of the GaSb(100) surface by any (NH_4)_2S solution leads to removal of the native oxide layer from the semiconductor surface and the formation of a passivating layer consisting of various gallium and antimony sulfides and oxides. The surface with the lowest roughness (RMS = 0.85 nm) is formed after semiconductor treatment with 4% aqueous ammonium sulfide solution for 30 min. Herewith, the atomic concentration ratio Ga/Sb at the surface is ~2. It is also found that aqueous ammonium sulfide solutions do not react with elemental antimony incorporated into the native-oxide layer. The latter causes a leakage current and Fermi-level pinning at the GaSb(100) surface. However, a 4% (NH_4)_2S solution in isopropanol removes elemental antimony almost completely; herewith, the semiconductor surface remains stoichiometric if a treatment duration is up to 13 min.

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Photoluminescence properties of cuprous phosphide prepared through phosphating copper with a native oxide layer

RSC Advances ◽

10.1039/d1ra07112b ◽

2021 ◽

Vol 11 (54) ◽

pp. 34095-34100

Author(s):

Xue Peng ◽

Yanfei Lv ◽

Li Fu ◽

Fei Chen ◽

Weitao Su ◽

...

Keyword(s):

Oxide Layer ◽

Cuprous Oxide ◽

Fluorescence Properties ◽

Native Oxide ◽

Native Oxide Layer ◽

Photoluminescence Properties ◽

Band Bending ◽

Carrier Traps

The presence of cuprous oxide results in band bending at the interface between cuprous phosphide and cuprous oxide, forming carrier traps, which improves the fluorescence properties of cuprous phosphide.

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