Electron glass effects in amorphous NbSi films

We report on non equilibrium field effect in insulating amorphous NbSi thin films having different Nb contents and thicknesses. The hallmark of an electron glass, namely the logarithmic growth of a memory dip in conductance versus gate voltage curves, is observed in all the films after a cooling from room temperature to 4.2~K. A very rich phenomenology is demonstrated. While the memory dip width is found to strongly vary with the film parameters, as was also observed in amorphous indium oxide films, screening lengths and temperature dependence of the dynamics are closer to what is observed in granular Al films. Our results demonstrate that the differentiation between continuous and discontinuous systems is not relevant to understand the discrepancies reported between various systems in the electron glass features. We suggest instead that they are not of fundamental nature and stem from differences in the protocols used and in the electrical inhomogeneity length scales within each material.

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Transport Properties of Granular Nix(SiO2)100−x Thin Films

MRS Proceedings ◽

10.1557/proc-195-129 ◽

1990 ◽

Vol 195 ◽

Cited By ~ 1

Author(s):

John R. Beamish ◽

B.M. Patterson ◽

K.M. Unruh

Keyword(s):

Thin Films ◽

Temperature Dependence ◽

Electrical Transport ◽

Low Temperatures ◽

Room Temperature ◽

Volume Percent ◽

Ni Content ◽

Resistivity Minimum ◽

Temperature Coefficient Of Resistivity ◽

Sputter Deposited

ABSTRACTWe have studied the electrical transport behavior of sputter deposited Nix(SiO2)100−x thin films between room temperature and 100 mK and, at selected temperatures, in applied magnetic fields up to 6 T. As the Ni concentration x is reduced, the resistivity increases systematically. At a Ni concentration (nominal) of about x–70 atomic percent (38 volume percent) the room temperature coefficient of resistivity changes sign. For Ni concentrations greater than 70 percent the resistance first decreases with temperature then increases logarithmically at, low temperatures. This increase becomes smaller and the resistivity minimum moves to progressively lower temperatures as the Ni concentration increases. In films with less than x–70 percent Ni, the resistivity has a temperature dependence of the form ρ(T)–ρo exp \(To/T)α] between room temperature and about 5 K. The exponent a is about 1/2 and To increases with decreasing Ni content. Below 1 K, however, the resistivity increases much less rapidly, with a temperature dependence independent of Ni concentration. In all films the magnetoresistance is small and negative.

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The effect of NaCl on room-temperature-processed indium oxide nanoparticle thin films for printed electronics

Applied Surface Science ◽

10.1016/j.apsusc.2016.11.060 ◽

2017 ◽

Vol 396 ◽

pp. 912-919 ◽

Cited By ~ 4

Author(s):

M. Häming ◽

T.T. Baby ◽

S.K. Garlapati ◽

B. Krause ◽

H. Hahn ◽

...

Keyword(s):

Thin Films ◽

Indium Oxide ◽

Room Temperature ◽

Printed Electronics ◽

Oxide Nanoparticle

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Transport Studies in Single-Crystal Films of Cosi2 and Nisi2

MRS Proceedings ◽

10.1557/proc-25-575 ◽

1983 ◽

Vol 25 ◽

Cited By ~ 4

Author(s):

J. C. Hensel ◽

R. T. Tung ◽

J. M. Poate ◽

F. C. Unterwald ◽

D. C. Jacobson

Keyword(s):

Thin Films ◽

Single Crystal ◽

Temperature Dependence ◽

Room Temperature ◽

Room Temperature Resistivity ◽

Transport Studies ◽

Single Crystal Films ◽

Crystal Films ◽

The Difference ◽

Temperature Resistivity

ABSTRACTTransport studies have been performed on thin films of CoSi 2 and NiSis2 in the temperature range 1 to 300 K. The conductivities are metallic with essentially the same temperature dependence; however, the residual resistivities are markedly different even though the two silicides are structurally similar (the room temperature resistivity of NiSi2 being at least twice that of CoSi2 of 15 μΩ cm). The difference is attributed to intrinsic defects in NiSi2. This defect has been simulated by ion bombardment of the film where it is also shown that Matthiesen's rule is obeyed over a remarkable range of bombardment doses.

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Properties of amorphous tin-doped indium oxide thin films deposited by O2/Ar mixture ion beam-assisted system at room temperature

Surface and Coatings Technology ◽

10.1016/s0257-8972(00)00825-2 ◽

2000 ◽

Vol 131 (1-3) ◽

pp. 201-205 ◽

Cited By ~ 23

Author(s):

H.J. Kim ◽

J.W. Bae ◽

J.S. Kim ◽

K.S. Kim ◽

Y.C. Jang ◽

...

Keyword(s):

Thin Films ◽

Indium Oxide ◽

Room Temperature ◽

Ion Beam ◽

Oxide Thin Films

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Dielectric Properties of Pulsed Excimer Laser Ablated BaBi2Nb2O9 Thin Films

MRS Proceedings ◽

10.1557/proc-748-u6.6 ◽

2002 ◽

Vol 748 ◽

Author(s):

Apurba Laha ◽

S. B. Krupanidhi ◽

S. Saha

Keyword(s):

Thin Films ◽

Phase Transition ◽

Dielectric Constant ◽

Temperature Dependence ◽

Loss Tangent ◽

Dielectric Response ◽

Room Temperature ◽

Dielectric Constant And Loss ◽

Wide Range ◽

Room Temperature Dielectric Constant

ABSTRACTThe dielectric response of BaBi2Nb2O9 (BBN) thin films has been studied as a function of frequency over a wide range of temperatures. Both dielectric constant and loss tangent of BBN thin films showed a ‘power law’ dependence with frequency, which was analyzed using the Jonscher's universal dielectric response model. Theoretical fits were utilized to compare the experimental results and also to estimate the value of temperature dependence parameters such as n(T) and a(T) used in the Jonscher's model. The room temperature dielectric constant (ε') of the BBN thin films was 214 with a loss tangent (tanδ) of 0.04 at a frequency of 100 kHz. The films exhibited the second order dielectric phase transition from ferroelectric to paraelectric state at a temperature of 220 °C. The nature of phase transition was confirmed from the temperature dependence of dielectric constant and sponteneous polarization,respectively. The calculated Currie constant for BBN thin films was 4 × 105°C.

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Tungsten Doped Indium Oxide Thin Films Deposited at Room Temperature by Radio Frequency Magnetron Sputtering

Journal of Material Science and Technology ◽

10.1016/j.jmst.2013.10.023 ◽

2014 ◽

Vol 30 (7) ◽

pp. 644-648 ◽

Cited By ~ 5

Author(s):

Jiaojiao Pan ◽

Wenwen Wang ◽

Dongqi Wu ◽

Qiang Fu ◽

Ding Ma

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Radio Frequency ◽

Indium Oxide ◽

Room Temperature ◽

Radio Frequency Magnetron ◽

Radio Frequency Magnetron Sputtering ◽

Oxide Thin Films

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Electron glass signatures up to room temperature in disordered insulators

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ac4a56 ◽

2022 ◽

Author(s):

Julien Delahaye ◽

Thierry Grenet

Keyword(s):

Thin Films ◽

Equilibrium State ◽

Gate Voltage ◽

Room Temperature ◽

Cryogenic Temperatures ◽

Field Effects ◽

Non Equilibrium

Abstract This paper describes the observation of non-equilibrium ﬁeld eﬀects at room temperature in four disordered insulating systems: granular Al, discontinuous Au, amorphous NbSi and amorphous InOx thin ﬁlms. The use of wide enough gate voltage ranges and a cautious analysis of the data allow us to uncover memory dips, the advocated hallmark of the electron glass, in the four systems. These memory dips are found to relax slowly over days of measurements under gate voltage changes, reﬂecting the impossibility for the systems to reach an equilibrium state within experimentally accessible times. Our ﬁndings demonstrate that these electrical glassy eﬀects, so far essentially reported at cryogenic temperatures, actually extend up to room temperature.

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Nanostructured Indium Oxide Thin Films as a Room Temperature Toluene Sensor

ACS Omega ◽

10.1021/acsomega.1c01831 ◽

2021 ◽

Author(s):

Sunil Gavaskar Dasari ◽

Pothukanuri Nagaraju ◽

Vijayakumar Yelsani ◽

Sreekanth Tirumala ◽

Ramana Reddy M V

Keyword(s):

Thin Films ◽

Indium Oxide ◽

Room Temperature ◽

Oxide Thin Films

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Thermal Transport in Few-Quintuple Bi2Te3 Thin Films and Nanoribbons

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44540 ◽

2011 ◽

Author(s):

Bo Qiu ◽

Xiulin Ruan

Keyword(s):

Thin Films ◽

Thermal Conductivity ◽

Molecular Dynamics ◽

Temperature Dependence ◽

Thermal Transport ◽

Room Temperature ◽

Phonon Scattering ◽

Md Simulations ◽

Boundary Scattering ◽

Nanoporous Films

In this work, thermal conductivity of perfect and nanoporous few-quintuple Bi2Te3 thin films as well as nanoribbons with perfect and zig-zag edges is investigated using molecular dynamics (MD) simulations with Green-Kubo method. We find minimum thermal conductivity of perfect Bi2Te3 thin films with three quintuple layers (QLs) at room temperature, and we believe it originates from the interplay between inter-quintuple coupling and phonon boundary scattering. Nanoporous films and nanoribbons are studied for additional phonon scattering channels in suppressing thermal conductivity. With 5% porosity in Bi2Te3 thin films, the thermal conductivity is found to decrease by a factor of 4–6, depending on temperature, comparing to perfect single QL. For nanoribbons, width and edge shape are found to strongly affect the temperature dependence as well as values of thermal conductivity.

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