Relationship between variable range hopping transport and carrier density of amorphous In2O3–10 wt. % ZnO thin films

In this paper, copper oxide (CuOx) thin films with amorphous phase were prepared on glass substrates by reactive dc magnetron sputtering. The influence of the flow rate of O2 on the structural, optical and electrical properties of the as-deposited films was systematically studied. XRD revealed that the as-deposited films remained amorphous in the whole range of adjusted oxygen flow rate. Surface morphology and nanoparticle size of the films were observed by AFM. Electrical resistivity and Hall effect measurements were performed on the films with van der Pauw configuration. The positive sign of the Hall coefficient confirmed the p-type conductivity in all studied films. From temperature-dependent electrical conductivity of the films prepared at R(O2) of 1.5 sccm, it was show that three types of behavior can be expected, nearest-neighbor hopping at high temperature range (200-300 K), the Mott variable range hopping at low temperature (110-190 K) and Efros-Shklovskii variable range hopping at very low temperature (65-100 K). Some important parameters corresponding to Mott-VRH and ES-VRH like density of localized states near the Fermi level, localization length, degree of disorder, hopping distance and hopping energy were determined. These parameters would be helpful for optimizing the performance of photovoltaic applications.

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Variable Range Hopping in Single-Wall Carbon Nanotube Thin Films: A Processing–Structure–Property Relationship Study

Langmuir ◽

10.1021/la401264r ◽

2013 ◽

Vol 29 (27) ◽

pp. 8694-8702 ◽

Cited By ~ 30

Author(s):

Sida Luo ◽

Tao Liu ◽

Shermane M. Benjamin ◽

James S. Brooks

Keyword(s):

Thin Films ◽

Carbon Nanotube ◽

Variable Range Hopping ◽

Structure Property ◽

Single Wall Carbon Nanotube ◽

Single Wall Carbon ◽

Variable Range ◽

Property Relationship ◽

Structure Property Relationship ◽

Relationship Study

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Variable range hopping conduction in ZnO nanocrystal thin films

Nanotechnology ◽

10.1088/1361-6528/aad6ce ◽

2018 ◽

Vol 29 (41) ◽

pp. 415202 ◽

Cited By ~ 2

Author(s):

Brian T Benton ◽

Benjamin L Greenberg ◽

Eray Aydil ◽

Uwe R Kortshagen ◽

S A Campbell

Keyword(s):

Thin Films ◽

Hopping Conduction ◽

Variable Range Hopping ◽

Variable Range ◽

Variable Range Hopping Conduction ◽

Zno Nanocrystal

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Decrease in Work Function of Boron Ion-Implanted ZnO Thin Films

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.086 ◽

2007 ◽

Vol 7 (11) ◽

pp. 4021-4024 ◽

Cited By ~ 4

Author(s):

Gi-Seok Heo ◽

Sang-Jin Hong ◽

Jong-Woon Park ◽

Bum-Ho Choi ◽

Jong-Ho Lee ◽

...

Keyword(s):

Thin Films ◽

Ion Implantation ◽

Work Function ◽

Carrier Density ◽

Carrier Mobility ◽

Optical Transmittance ◽

Zno Thin Films ◽

Electrical And Optical Properties ◽

Visible Wavelength Range ◽

Ion Implanted

We have fabricated boron ion-implanted ZnO thin films by ion implantation into sputtered ZnO thin films on a glass substrate. An investigation of the effects of ion doses and activation time on the electrical and optical properties of the films has been made. The electrical sheet resistance and resistivity of the implanted films are observed to increase with increasing rapid thermal annealing (RTA)time, while decreasing as the ion dose increases. Without any RTA process, the variation of the carrier density is insensitive to the ion dose. With the RTA process, however, the carrier density of the implanted films increases and approaches that of the un-implanted ZnO film as the ion dose increases. On the other hand, the carrier mobility is shown to decrease with increasing ion doses when no RTA process is applied. With the RTA process, however, there is almost no change in the mobility. We have achieved the optical transmittance as high as 87% within the visible wavelength range up to 800 nm. It is also demonstrated that the work function can be engineered by changing the ion dose during the ion implantation process. We have found that the work function decreases as the ion dose increases.

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Non variable range hopping transport on doped polypyrrole films

10.1109/stsm.1994.834761 ◽

1994 ◽

Author(s):

F.L. dos Santos ◽

C.P. de Melo

Keyword(s):

Variable Range Hopping ◽

Hopping Transport ◽

Variable Range ◽

Polypyrrole Films

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High Temperature Variable Range Hopping in Heavy Al Implanted 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.858.283 ◽

2016 ◽

Vol 858 ◽

pp. 283-286 ◽

Cited By ~ 3

Author(s):

Antonella Parisini ◽

Andrea Parisini ◽

Marco Gorni ◽

Roberta Nipoti

Keyword(s):

Electrical Transport ◽

Room Temperature ◽

Hole Transport ◽

Variable Range Hopping ◽

Electrical Transport Properties ◽

Hopping Transport ◽

Variable Range ◽

Transmission Electron ◽

Temperature Variable ◽

Post Implantation

In this work, we confirm and extend the results of a previous study where a variable range hopping transport through localized impurity states has been found to dominate the electrical transport properties of 3×1020 cm-3 and 5×1020 cm-3 Al+ implanted 4H-SiC layers after 1950-2000 °C post implantation annealing. In this study, samples with longer annealing times have been taken into account. The temperature dependence of these sample conductivity follows a variable range hopping law, consistent with a nearly two-dimensional hopping transport of non-interacting carriers that in the highest doped samples, persists up to around room temperature. This result indicates that the hole transport becomes strongly anisotropic on increasing the doping level. At the origin of this unusual electrical behavior, may be the presence of basal plane stacking faults, actually observed by transmission electron microscopy in one of the 5×1020 cm-3 samples

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