Charge transport in thin layers of ferroelectric Hf0.5Zr0.5O2

AbstractIn this study, we developed a discrete theory of the charge transport in thin dielectric films by trapped electrons or holes, that is applicable both for the case of countable and a large number of traps. It was shown that Shockley–Read–Hall-like transport equations, which describe the 1D transport through dielectric layers, might incorrectly describe the charge flow through ultra-thin layers with a countable number of traps, taking into account the injection from and extraction to electrodes (contacts). A comparison with other theoretical models shows a good agreement. The developed model can be applied to one-, two- and three-dimensional systems. The model, formulated in a system of linear algebraic equations, can be implemented in the computational code using different optimized libraries. We demonstrated that analytical solutions can be found for stationary cases for any trap distribution and for the dynamics of system evolution for special cases. These solutions can be used to test the code and for studying the charge transport properties of thin dielectric films.

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Поляризационные процессы в тонких слоях аморфного MoS-=SUB=-2-=/SUB=-, полученных методом высокочастотного магнетронного распыления

Физика и техника полупроводников ◽

10.21883/ftp.2020.05.49262.9345 ◽

2020 ◽

Vol 54 (5) ◽

pp. 461

Author(s):

А.А. Кононов ◽

Р.А. Кастро Арата ◽

Д.Д. Главная ◽

В.М. Стожаров ◽

Д.М. Долгинцев ◽

...

Keyword(s):

Relaxation Time ◽

Charge Transport ◽

Relaxation Process ◽

Molybdenum Disulfide ◽

Dielectric Spectroscopy ◽

Activation Energies ◽

Thin Layers ◽

Polarization Process ◽

Relaxation Polarization ◽

Dipole Polarization

Abstract The polarization processes in thin layers of amorphous molybdenum disulfide MoS_2 are studied by dielectric spectroscopy techniques. The process of dipole-relaxation polarization is observed. The microscopic parameters of the system are calculated, and the relaxation time of the dipole-polarization process, as well as the activation energies E _ a and E _σ of the relaxation process and conductivity, respectively, are determined. The fact that the two activation energies are close to each other suggests that the processes of relaxation and charge transport are driven by the same mechanism.

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Charge transport in thin layers of organic crystals

Journal of Physics Conference Series ◽

10.1088/1742-6596/30/1/037 ◽

2006 ◽

Vol 30 ◽

pp. 307-320 ◽

Cited By ~ 1

Author(s):

Marian Kuzma

Keyword(s):

Charge Transport ◽

Thin Layers ◽

Organic Crystals

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Markov jump transport of trapped charge in thin dielectric layers

10.21203/rs.3.rs-121844/v1 ◽

2020 ◽

Author(s):

Andrey Pil'nik ◽

Andrey Chernov ◽

Damir Islamov

Keyword(s):

Charge Transport ◽

Theoretical Models ◽

Thin Layers ◽

Dielectric Films ◽

Algebraic Equations ◽

Markov Jump ◽

Dielectric Layers ◽

Linear Algebraic Equations ◽

Special Cases ◽

Thin Dielectric Films

Abstract In this study, we developed a discrete theory of the charge transport in thin dielectric films by trapped electrons or holes, that is applicable both for the case of countable and a large number of traps. It was shown that Shockley-Read-Hall-like transport equations, which describe 1D transport through dielectric layers, might incorrectly describe the charge flow through the ultra-thin layers with a countable number of traps, taking into account injection-from and extraction-to electrodes (contacts). A comparison with other theoretical models shows a good agreement. The developed model can be applied to one-, two- and three-dimensional systems. The model, formulated in a system of linear algebraic equations, can be implemented in the computational code using different optimized libraries. We demonstrated that analytical solutions can be found for stationary cases for any trap distribution and for dynamics of system evolution for special cases. These solutions can be used to test the code and for studying of charge transport properties of thin dielectric films.

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The Influence of Material Density on Bipolar Charge Transport in Polymer-Based Electronic Applications

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.882 ◽

2006 ◽

Vol 514-516 ◽

pp. 882-886

Author(s):

Marta M. D. Ramos ◽

Helena M.G. Correia ◽

Hugo Carmo

Keyword(s):

Charge Transport ◽

Computer Experiments ◽

Film Structure ◽

Thin Layers ◽

Semiconducting Polymers ◽

Key Factors ◽

Material Density ◽

Polymer Density ◽

Bipolar Charge ◽

Modelling Approach

Using a mesoscopic modelling approach, the authors performed computer experiments to study the influence of polymer density on bipolar charge evolution through thin layers of polydiacetylene (PDA) exhibiting specific microstructures. We found that the competition between charge transport, trapping and recombination within the polymer layer leads to several general trends, some of them being non-intuitive, as one varies polymer density. Our results show that polymer density mainly affects current and recombination efficiencies in the absence of defects or impurity states. The overall trends depend both on chain orientation relative to the electrodes and on the strength of the external applied electric field. These results suggest that adequate modelling of charge transport in electronic and optoelectronic devices based on conducting and semiconducting polymers, such as PDA, must include their structure and related key factors at mesoscopic scale. Such models provide the necessary knowledge-base to optimize the polymer film structure for electronic applications.

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An analytic modelling of charge transport in thin layers of disordered organic materials

Journal of Physics Conference Series ◽

10.1088/1742-6596/938/1/012069 ◽

2017 ◽

Vol 938 ◽

pp. 012069 ◽

Cited By ~ 1

Author(s):

M D Khan ◽

V R Nikitenko ◽

Ya V Burdakov

Keyword(s):

Charge Transport ◽

Organic Materials ◽

Thin Layers

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Immunoferritin localization of intracellular antigens in positively stained frozen sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010008170x ◽

1978 ◽

Vol 36 (2) ◽

pp. 168-169

Author(s):

K. T. Tokuyasu

Keyword(s):

Surface Tension ◽

Water Surface ◽

Thin Layers ◽

The Other ◽

Positive Staining ◽

Frozen Sections ◽

The Past ◽

Ultrathin Frozen Sections ◽

Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

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EELS Measurement of the Local Electronic Structure of Copper Atoms Segregated to Aluminum Grain Boundaries

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164179 ◽

1996 ◽

Vol 54 ◽

pp. 342-343

Author(s):

S.J. Splinter ◽

J. Bruley ◽

P.E. Batson ◽

D.A. Smith ◽

R. Rosenberg

Keyword(s):

Electronic Structure ◽

Grain Boundaries ◽

Boundary Segregation ◽

Thin Layers ◽

Nominal Composition ◽

Spatially Resolved ◽

Service Lifetime ◽

Heat Treated ◽

Probe Size ◽

Local Electronic Structure

It has long been known that the addition of Cu to Al interconnects improves the resistance to electromigration failure. It is generally accepted that this improvement is the result of Cu segregation to Al grain boundaries. The exact mechanism by which segregated Cu increases service lifetime is not understood, although it has been suggested that the formation of thin layers of θ-CuA12 (or some metastable substoichiometric precursor, θ’ or θ”) at the boundaries may be necessary. This paper reports measurements of the local electronic structure of Cu atoms segregated to Al grain boundaries using spatially resolved EELS in a UHV STEM. It is shown that segregated Cu exists in a chemical environment similar to that of Cu atoms in bulk θ-phase precipitates.Films of 100 nm thickness and nominal composition Al-2.5wt%Cu were deposited by sputtering from alloy targets onto NaCl substrates. The samples were solution heat treated at 748K for 30 min and aged at 523K for 4 h to promote equilibrium grain boundary segregation. EELS measurements were made using a Gatan 666 PEELS spectrometer interfaced to a VG HB501 STEM operating at 100 keV. The probe size was estimated to be 1 nm FWHM. Grain boundaries with the narrowest projected width were chosen for analysis. EDX measurements of Cu segregation were made using a VG HB603 STEM.

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