Develop Single-Phase High Dielectric Constant SiO2-Based Composite Gate Dielectric

2010 ◽  
Vol 434-435 ◽  
pp. 259-262
Author(s):  
Chao Chin Chan ◽  
Yin Fang Wei ◽  
Chien Chen Diao ◽  
Yuan Tai Hsieh ◽  
Ping Shou Cheng
Keyword(s):  
Single Phase ◽  
High Dielectric Constant ◽  
Gate Dielectric ◽  
Raw Materials ◽  
Ceramic Materials ◽  
Dielectric Constants ◽  
Dielectric Characteristics ◽  
X Ray ◽  
High Dielectric ◽  
Ray Patterns

In this study, we hoped to find the single-phase high dielectric FET gate-used ceramic materials, which will be used in the sputtering method and have the dielectric constants higher than those of SiO2 and Si3N4. TiO2, La2O3 and ZrO2 are mixed with SiO2 to format the (1-x) TiO2-x SiO2, (1-x) ZrO2-x SiO2 and (1-x) La2O3-x SiO2 compositions, where x is dependent on the different raw materials. The all compositions are calcined at 1100oC and sintered at 1400oC~ 1550oC for 2hrs, and the X-ray patterns are used to find the crystal phases of all sintered ceramics. Because of the existence of single-phase, the sintering and dielectric characteristics of 0.3 La2O3-0.7 SiO2 ceramic are further developed.

scholarly journals Rapid processing of ferrite ceramics with promising magneto-dielectric characteristics

2017 ◽  
Vol 07 (06) ◽  
pp. 1750040 ◽  
Author(s):  
Zhuohao Xiao ◽  
Chuanhu Wang ◽  
Lie Liu ◽  
Zhihong Yang ◽  
Ling Bing Kong
Keyword(s):  
Single Phase ◽  
Ceramic Materials ◽  
X Ray Diffraction ◽  
Time Duration ◽  
Dielectric Characteristics ◽  
Sintering Aid ◽  
X Ray ◽  
Sintering Time ◽  
One Step ◽  
Rapid Processing

Ferrite ceramics, Ni[Formula: see text]Zn[Formula: see text]Co[Formula: see text]Fe[Formula: see text]O4, with the addition of 4[Formula: see text]wt.% Bi2O3 as sintering aid, were fabricated by using a simple one-step processing without involving the step of calcination. X-ray diffraction (XRD) results indicated that single phase ferrite ceramics can be achieved after sintering at 1000[Formula: see text]C for 2[Formula: see text]h. The samples demonstrated relative densities in the range of 97–99%. Desired magneto-dielectric properties have been approached by adjusting the sintering temperature and sintering time duration. This technique is believed to be applicable to other ceramic materials.

Microstructure, Crystalline Phase, and Dielectric Property Analyses of TiO2 Composition with ZrO2 Addition

2010 ◽  
Vol 660-661 ◽  
pp. 641-645
Author(s):  
José Vitor C. Souza ◽  
Pedro José Castro ◽  
Maria do Carmo de Andrade Nono ◽  
Sergio Luiz Mineiro
Keyword(s):  
High Dielectric Constant ◽  
Raw Materials ◽  
Weight Ratio ◽  
Satellite Communications ◽  
Dielectric Constants ◽  
Sintering Behavior ◽  
Dielectric Losses ◽  
Low Dielectric ◽  
A Value ◽  
High Dielectric

For microwave applications, including mobile and satellite communications, ceramic resonators should have a high dielectric constant, low dielectric losses, and high frequency stability. In this sense, TiO2-ZrO2 ceramics have been investigated as a function of sintering behavior, phase composition, and microstructure. The ceramics were densified reaching a value of about 86% of theoretical density at 1400°C sintering temperature. The ceramics are prepared by mixing raw materials with the following TiO2-ZrO2 weight % ratio: 100 to 0, 90 to 10, and 80 to 20, respectively. The measured dielectric constants are between 79 and 88 values, while the quality factor due to dielectric losses are between 2820 and 5170. These results point out the influence of Ti/Zr ratio on controlling the dielectric properties.

Structural and dielectric properties of Ca1-x MgxCu3Ti4O12 thin films

2003 ◽  
Vol 785 ◽  
Author(s):  
L. A. Bermúdez ◽  
R. P. Guzman ◽  
M.S. Tomar ◽  
R.E. Melgarejo
Keyword(s):  
Thin Films ◽  
Single Phase ◽  
High Dielectric Constant ◽  
Film Material ◽  
X Ray Diffraction ◽  
Detailed Characterization ◽  
Chemical Route ◽  
X Ray ◽  
High Dielectric

ABSTRACTCa1-xMgxCu3Ti4O12 material has been synthesized by chemical route for different compositions and thin films have been deposited by spin coating. X-ray diffraction and Raman spectroscopy were used for detailed characterization of this material for both powder and thin films. X-ray diffraction shows single phase film material for different compositions x < 0.80. The initial measurements on dielectric response indicates high dielectric constant > 10, 000 for the composition x = 0.1.

scholarly journals Synthesis of Graphene-Based Nanocomposite and Investigations of Its Thermal and Electrical Properties

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Manoj Kumar Pati ◽  
Puspalata Pattojoshi ◽  
Gouri Sankar Roy
Keyword(s):  
High Dielectric Constant ◽  
Interfacial Polarization ◽  
Dielectric Constants ◽  
Functionalized Graphene ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal And Electrical Properties ◽  
High Dielectric ◽  
Polymerization Conditions

We describe the synthesis of acid functionalized graphene (GE) which is grafted to chitosan (CH) by first reacting the oxidized GE with thionyl chloride to form acyl-chlorinated GE. This product is subsequently dispersed in chitosan and covalently grafted to form GE-chitosan. GE-chitosan is further grafted onto polymetanitroaniline (PMNA) by free radical polymerization conditions to yield GE-CH-PMNA. We have characterized the structure of synthesized GE-CH-PMNA composites by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy, and conductivity measurements. XRD data suggest the strongly crystalline character of the prepared specimen. Our measurement shows that the dielectric constants of these nanocomposites are remarkably enhanced due to interfacial polarization effect. This study demonstrates that functionalized graphene sheets are ideal nanofillers for the development of new polymer composites with high dielectric constant values.

scholarly journals Preparation of basalt-based glass ceramics

2003 ◽  
Vol 68 (6) ◽  
pp. 505-510 ◽  
Author(s):  
Branko Matovic ◽  
Snezana Boskovic ◽  
Mihovil Logar
Keyword(s):  
Optical Microscopy ◽  
Phase Analysis ◽  
Glass Ceramic ◽  
Glassy Phase ◽  
Raw Materials ◽  
Glass Ceramics ◽  
High Strength ◽  
Ceramic Materials ◽  
X Ray ◽  
Glass Ceramic Materials

Local and conventional raw materials?massive basalt from the Vrelo locality on Kopaonik mountain?have been used as starting materials to test their suitability for the production of glass-ceramics. Crystallization phenomena of glasses of the fused basalt rocks were studied by X-ray phase analysis optical microscopy and other techniques. Various heat treatments were used and their influences, on controlling the microstructures and properties of the products were studied with the aim of developing high strength glass-ceramic materials. Diopside CaMg(SiO3)2 and hypersthene ((Mg,Fe)SiO3) were identifies as the crystalline phases. The final products contained considerable amounts of a glassy phase. The crystalline size was in range of 8?480 ?m with plate or needle shape. Microhardness, crashing strength and wears resistence of the glass-ceramics ranged from 6.5?7.5, from 2000?6300 kg/cm2 and from 0.1?0.2 g/cm, respectively.

scholarly journals Utilization of discarded foundry sand (DFS) and inorganic waste from cellulose and paper industry for the manufacture of glass-ceramic materials

Cerâmica ◽  
2020 ◽  
Vol 66 (380) ◽  
pp. 413-420
Author(s):  
L. M. S. e Silva ◽  
R. S. Magalhães ◽  
W. C. Macedo ◽  
G. T. A. Santos ◽  
A. E. S. Albas ◽  
...  
Keyword(s):  
Glass Ceramic ◽  
Raw Materials ◽  
Paper Industry ◽  
Glass Ceramics ◽  
Ceramic Materials ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Foundry Sand ◽  
X Ray ◽  
Glass Ceramic Materials

Abstract Recycling has been pointed out as an alternative to the disposal of waste materials in industrial landfills. In the present study, the transformation of residues (discarded foundry sand - DFS, grits, and lime mud) in glass-ceramic materials is shown. The glasses were obtained by the melting/cooling method. The precursor materials, glasses, and glass-ceramics were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), and differential scanning calorimetry/thermal gravimetric analysis (DSC/TGA). The glassy materials were milled, pelleted, and thermally treated at the crystallization temperatures given by DSC data to obtain the glass-ceramics (885, 961, and 1090 ºC). The main formed phases were cristobalite, α-wollastonite (parawollastonite), and β-wollastonite (pseudowollastonite). The glass-ceramics showed very low water absorption and apparent porosity (0.26 to 0.88 wt% and 0.66 to 1.77 vol%, respectively). The results confirmed that the studied residues can be used as raw materials for the manufacture of vitreous and glass-ceramic materials.

Lattice Parameters of Bronze-Type 3BaO·2R2O3·9TiO2 (R=Sm and Nd) Solid Solutions for Microwave Dielectric Ceramics

1993 ◽  
Vol 37 ◽  
pp. 79-85 ◽  
Author(s):  
Hitoshi Ohsato ◽  
Toshiyuki Ohhashi ◽  
Kazuhiko Sumiya ◽  
Shinya Suzuki ◽  
Takashi Okuda
Keyword(s):  
Low Temperature ◽  
High Dielectric Constant ◽  
Dielectric Constants ◽  
Dielectric Resonators ◽  
Microwave Dielectric Ceramics ◽  
Low Dielectric ◽  
Satellite Broadcasting ◽  
Microwave Dielectric ◽  
Dielectric Ceramics ◽  
High Dielectric

Microwave dielectric ceramics with high quality have received attention due to the rapid progress in microwave telecommunication and satellite broadcasting. The desirable properties in microwave dielectric resonators are a high dielectric constant (εr), low dielectric loss (tanδ) (i.e. high Q (Q =1/tanδ)), and low temperature coefficient of the resonant frequency(τf). Properties of dielectric ceramics in the TiO2-rich region of the BaO-Nd2O3-TiO2 ternary system (Fig. 1) were reported to have excellent dielectric constants, low dielectric losses and low temperature coefficients of capacitance by Kolar et al. (1978).

Plasma Enhanced Mocvd of BaTiO3 Films

1991 ◽  
Vol 243 ◽  
Author(s):  
Peter C. Van Buskirk ◽  
Robin Gardiner ◽  
Peter S. Kirlin ◽  
Salora Krupanidhi ◽  
Steven Nutt
Keyword(s):  
Single Phase ◽  
Chemical Vapor ◽  
Dielectric Constants ◽  
Polycrystalline Films ◽  
Fine Grained ◽  
Selected Area Electron Diffraction ◽  
Electro Optic ◽  
Ir Reflectance ◽  
High Dielectric ◽  
Very High

AbstractBulk BaTiO3 has a large linear electro-optic coefficient and a very high dielectric constant. We report results obtained for two different MOCVD processes designed to deposit BaTiO3 films with properties suitable for nonlinear electro-optic or high charge storage applications. Epitaxial BaTiO3 films have been grown on NdGaO3 [100] substrates using a high temperature thermal process; the substrate temperature was 1000°C and the total pressure was 4 torr. Selected area electron diffraction (SAED) measurements indicate highly textured, single phase films on the NdGaO3 substrate which are predominantly [100] oriented. Fine grained polycrystalline films have been grown on Pt at 600°C by plasma-enhanced metalorganic chemical vapor deposition (PEMOCVD). Specular IR reflectance was used to determine the concentration of BaCO3 in the film, which was significantly reduced by the plasma. The polycrystalline films had dielectric constants as large as 300 and resistivities exceeding 5 x 108 Ω-cm at room temperature.

Preparation of Manganese Ferrite Powders by Mechanochemical Process

2011 ◽  
Vol 284-286 ◽  
pp. 2268-2271 ◽  
Author(s):  
Ju Hua Luo
Keyword(s):  
Single Phase ◽  
Raw Materials ◽  
Vibrating Sample Magnetometry ◽  
X Ray Diffraction ◽  
Mechanochemical Method ◽  
X Ray ◽  
Starting Mixture ◽  
Ft Ir ◽  
Mechanochemical Treatments ◽  
Firing Method

Mn-ferrite powders were prepared by mechanochemical treatments using MnO2and Fe2O3as raw materials. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometry (VSM) were employed to evaluated the morphologies and structures of samples. The results indicated that the starting mixture became amorphous stage after ball-milled for 40h, and single phase MnFe2O4could be obtained after annealed at 1200°C for 2h. In comparison with the traditional firing method , the mechanochemical method benefited achieving the higher saturation magnetization, which indicated that the samples had a better magnetic properties.

Sign in / Sign up

Export Citation Format

Share Document