Dielectric properties of BaMg1∕3Nb2∕3O3 doped Ba0.45Sr0.55Tio3 thin films for tunable microwave applications

Ba(Mg[Formula: see text]Nb[Formula: see text]O3 (BMN) doped and undoped Ba[Formula: see text]Sr[Formula: see text]TiO3 (BST) thin films were deposited via radio frequency magnetron sputtering on Pt/TiO2/SiO2/Al2O3 substrates. The surface morphology and chemical state analyses of the films have shown that the BMN doped BST film has a smoother surface with reduced oxygen vacancy, resulting in an improved insulating properties of the BST film. Dielectric tunability, loss, and leakage current (LC) of the undoped and BMN doped BST thin films were studied. The BMN dopant has remarkably reduced the dielectric loss ([Formula: see text]38%) with no significant effect on the tunability of the BST film, leading to an increase in figure of merit (FOM). This is attributed to the opposing behavior of large Mg[Formula: see text] whose detrimental effect on tunability is partially compensated by small Nb[Formula: see text] as the two substitute Ti[Formula: see text] in the BST. The coupling between [Formula: see text] and V[Formula: see text] charged defects suppresses the dielectric loss in the film by cutting electrons from hopping between Ti ions. The LC of the films was investigated in the temperature range of 300–450[Formula: see text]K. A reduced LC measured for the BMN doped BST film was correlated to the formation of defect dipoles from [Formula: see text], V[Formula: see text] and Nb[Formula: see text] charged defects. The carrier transport properties of the films were analyzed in light of Schottky thermionic emission (SE) and Poole–Frenkel (PF) emission mechanisms. The result indicated that while the carrier transport mechanism in the undoped film is interface limited (SE), the conduction in the BMN doped film was dominated by bulk processes (PF). The change of the conduction mechanism from SE to PF as a result of BMN doping is attributed to the presence of uncoupled Nb[Formula: see text] sitting as a positive trap center at the shallow donor level of the BST.

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Processing and Characterization of Pure and Doped Ba0.6Sr0.4TiO3 Thin Films for Tunable Microwave Applications

MRS Proceedings ◽

10.1557/proc-656-dd4.9 ◽

2000 ◽

Vol 656 ◽

Author(s):

P. C. Joshi ◽

M. W. Cole ◽

E. Ngo ◽

C. W. Hubbard

Keyword(s):

Thin Films ◽

Dielectric Loss ◽

Leakage Current ◽

Microwave Devices ◽

Silicon Substrates ◽

Electrical Measurements ◽

Bst Thin Films ◽

Tunable Microwave ◽

Current Characteristics ◽

And Control

ABSTRACTBa1−xSrxTiO3 thin films are being developed for high-density DRAM devices. The nonlinearity of its dielectric properties with respect to applied dc voltage makes it attractive for tunable microwave devices. For successful integration into microwave devices, extremely reliable Ba1−xSrxTiO3 thin films with enhanced dielectric and insulating properties are desired. Properties of Ba1−xSrxTiO3are typically varied by changing the Ba/Sr ratio and/or doping. In this paper, we reports on the effects of acceptor and donor doping on the microstructural and electrical properties of Ba0.6Sr0.4TiO3 (BST) thin films deposited by metalorganic solution deposition technique on platinum coated silicon substrates. The effects of doping on structure, dielectric permittivity, dielectric loss tangent, and leakage current have been analyzed. The structure of the films was analyzed by x-ray diffraction (XRD). The surface morphology of the films was examined by field emission scanning electron microscope (FESEM) and atomic force microscope (AFM). The electrical measurements were conducted on MIM capacitors using Pt as the top and bottom electrode. It was possible to significantly improve the dielectric loss and leakage current characteristics, and control the dielectric tunability by doping the BST thin films.

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A High Throughput Search of Dielectric Thin Films for Tunable Devices

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.2351 ◽

2006 ◽

Vol 45 ◽

pp. 2351-2354

Author(s):

Ji Won Choi ◽

Chong Yun Kang ◽

Jin Sang Kim ◽

Seok Jin Yoon ◽

Hyun Jai Kim ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Dielectric Properties ◽

Dielectric Loss ◽

Rf Magnetron Sputtering ◽

Dielectric Materials ◽

Si Substrate ◽

Dielectric Thin Films ◽

Low Dielectric ◽

Film Dielectric

The dielectric properties of (Ba,Sr)TiO3 (BSTO) and Zr doped BSTO thin films have been investigated to identify candidate thin film dielectric materials having low dielectric loss without degradation of the tunability by continuous composition spread (CCS) technique using off-axis rf magnetron sputtering. The optimized properties of BSTO thin films deposited on Pt/SiO2/Si substrate by CCS were dielectric loss 0.031, tunability 31.5, respectively. The optimized properties of Zr doped BSTO thin films deposited on Pt/SiO2/Si substrate by CCS were improved by dielectric loss 42%, FOM 68% at the same BSTO composition, respectively. To confirm the dielectric properties and compositions by CCS technique, Zr doped BSTO bulk ceramics were evaluated.

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Engineering Thin Films of a Tetrabenzoporphyrin toward Efficient Charge-Carrier Transport

10.29363/nanoge.iperop.2020.022 ◽

2019 ◽

Author(s):

Hiroko Yamada

Keyword(s):

Thin Films ◽

Charge Carrier ◽

Carrier Transport ◽

Charge Carrier Transport ◽

Efficient Charge

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IN-PLANE DIELECTRIC PROPERTIES OF BST THIN FILMS GROWN ON MgO SUBSTRATES USING THE THIN PEROVSKITE LAYERS FOR MICROWAVE TUNABLE ELECTRONICS

Integrated Ferroelectrics ◽

10.1080/10584580601085404 ◽

2006 ◽

Vol 86 (1) ◽

pp. 159-169 ◽

Cited By ~ 2

Author(s):

SU-JAE LEE ◽

HAN-CHEOL RYU ◽

YOUNG-TAE KIM ◽

MIN-HWAN KWAK ◽

SEUNGEON MOON ◽

...

Keyword(s):

Thin Films ◽

Dielectric Properties ◽

Bst Thin Films

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Effect of photon irradiation on structural, dielectric, and insulating properties of Ba0.60Sr0.40TiO3 thin films

Applied Physics Letters ◽

10.1063/1.2936305 ◽

2008 ◽

Vol 92 (21) ◽

pp. 212906 ◽

Cited By ~ 26

Author(s):

Adrian Podpirka ◽

M. W. Cole ◽

Shriram Ramanathan

Keyword(s):

Thin Films ◽

Photon Irradiation ◽

Insulating Properties

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Two-carrier transport in SrMnBi2 thin films

Frontiers of Physics ◽

10.1007/s11467-017-0663-0 ◽

2017 ◽

Vol 12 (3) ◽

Cited By ~ 4

Author(s):

Xiao Yan ◽

Cheng Zhang ◽

Shan-Shan Liu ◽

Yan-Wen Liu ◽

David Wei Zhang ◽

...

Keyword(s):

Thin Films ◽

Carrier Transport

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Identification of marcasite in pyrite FeS2 thin films and the films' carrier transport characteristics

RSC Advances ◽

10.1039/c6ra18581a ◽

2016 ◽

Vol 6 (84) ◽

pp. 81394-81399 ◽

Cited By ~ 6

Author(s):

Juran Kim ◽

Gee Yeong Kim ◽

Hankyoul Moon ◽

Seokhyun Yoon ◽

Il Wan Seo ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Carrier Transport ◽

Sulfurization Temperature ◽

Light Absorber

400 °C is optimal sulfurization temperature for pure pyrite FeS2 thin film, expecting better performance as light-absorber.

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Transient photocurrents as a spatially resolved probe of carrier transport and defect distributions in silicon thin films

Materials Science and Engineering B ◽

10.1016/j.mseb.2012.10.040 ◽

2013 ◽

Vol 178 (9) ◽

pp. 568-573

Author(s):

Steve Reynolds ◽

Rudi Brüggemann ◽

Björn Grootoonk ◽

Vlad Smirnov

Keyword(s):

Thin Films ◽

Carrier Transport ◽

Spatially Resolved ◽

Silicon Thin Films

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Large modulation of carrier transport by grain-boundary molecular packing and microstructure in organic thin films

Nature Materials ◽

10.1038/nmat2570 ◽

2009 ◽

Vol 8 (12) ◽

pp. 952-958 ◽

Cited By ~ 341

Author(s):

Jonathan Rivnay ◽

Leslie H. Jimison ◽

John E. Northrup ◽

Michael F. Toney ◽

Rodrigo Noriega ◽

...

Keyword(s):

Thin Films ◽

Grain Boundary ◽

Carrier Transport ◽

Organic Thin Films ◽

Molecular Packing

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Electrophysical properties of mixtures of mineral oil and synthetic ester dielectric liquid

Safety and Reliability of Power Industry ◽

10.24223/1999-5555-2021-14-2-132-141 ◽

2021 ◽

Vol 14 (2) ◽

pp. 132-141

Author(s):

M. N. Lyutikova ◽

S. M. Korobeynikov ◽

A. A. Konovalov

Keyword(s):

Dielectric Loss ◽

Breakdown Voltage ◽

Loss Tangent ◽

Dielectric Loss Tangent ◽

Kinematic Viscosity ◽

Mineral Oil ◽

Flash Point ◽

Power Transformers ◽

Synthetic Ester ◽

Insulating Properties

Power transformers are key equipment in power generation, transmission, and distribution systems. The reliability of power transformers is based on the performance of the insulation system, which includes solid cellulose insulation and a liquid dielectric. Modern power engineering requires liquid insulation to have excellent insulating properties, high fire resistance, and biodegradability. Mineral oil that has been in use for over 100 years does not meet certain requirements. Therefore, various methods of enhancing the insulating properties of the oil are currently being considered, including mixing it with other liquid dielectrics, which have excellent properties. Synthetic and natural esters are considered as alternative fluids.This article discusses the possibility of enhancing the insulating characteristics of mineral oil with a high content of aromatic hydrocarbons (for example, T-750 oil) by mixing it with synthetic ester Midel 7131. Assessment is given of insulating parameters of the resulting mixtures with an ester fraction in mineral oil from 0% to fifty%. The main characteristics of the mixtures are described, such as density, kinematic viscosity, flash point, dielectric loss tangent, relative dielectric permittivity, breakdown voltage, and moisture content. It is shown that with an increase in the proportion of ester, some parameters of the obtained insulating liquid improve (flash point, dielectric constant, breakdown voltage), while values of other parameters (density, kinematic viscosity, dielectric loss tangent) with an ester content of more than 10% in the mixture do not meet the requirements for mineral oils.

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