Dielectric and Sintering Properties of the Doping CaO-B2O3-SiO2 System Low Temperature Co-Fired Ceramics

2010 ◽  
Vol 434-435 ◽  
pp. 371-375
Author(s):  
Ming He ◽  
Shu Ren Zhang ◽  
Xiao Hua Zhou ◽  
Jian Geng Hu ◽  
Ting Zhang ◽  
...  

. A doping CaO-B2O3-SiO2 system low temperature co-fired ceramics (LTCC) was prepared with a mixture of high temperature melting glass and sol-gel glass for different ratio. The effects of sol-gel glass content on the microstructure, crystalline phases, sintering properties and dielectric properties of CaO-B2O3-SiO2 system were investigated at 850°C. The results show that the samples with sol-gel glass doping had little change in phase composition, but contained more calcium silicates, and less calcium borate. As the amount of sol-gel glass increased, the shrinkage improved, the sintered density slightly decreased, the dielectric constant (εr) reduced, and the dielectric loss (tgδ) decreased. When the amount of sol-gel glass was 14.5wt%, εr and tgδ of the doping sample were 5.80, 4.6×10-5 (at 1 MHz), respectively. Moreover, the doping system had a good matching ability with gold slurry and Au-Pt-Pd slurry.

2000 ◽  
Vol 617 ◽  
Author(s):  
Ian W. Boyd ◽  
Jun-Ying Zhang

AbstractIn this paper, UV-induced large area growth of high dielectric constant (Ta2O5, TiO2and PZT) and low dielectric constant (polyimide and porous silica) thin films by photo-CVD and sol-gel processing using excimer lamps, as well as the effect of low temperature LW annealing, are discussed. Ellipsometry, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), UV spectrophotometry, atomic force microscope (AFM), capacitance-voltage (C-V) and current-voltage (I-V) measurements have been employed to characterize oxide films grown and indicate them to be high quality layers. Leakage current densities as low as 9.0×10−8 Acm−2 and 1.95×10−7 Acm−2 at 0.5 MV/cm have been obtained for the as-grown Ta2O5 films formed by photo-induced sol-gel processing and photo-CVD. respectively - several orders of magnitude lower than for any other as-grown films prepared by any other technique. A subsequent low temperature (400°C) UV annealing step improves these to 2.0×10−9 Acm−2 and 6.4× 10−9 Acm−2, respectively. These values are essentially identical to those only previously formed for films annealed at temperatures between 600 and 1000°C. PZT thin films have also been deposited at low temperatures by photo-assisted decomposition of a PZT metal-organic sol-gel polymer using the 172 nm excimer lamp. Very low leakage current densities (10−7 A/cm2) can be achieved, which compared with layers grown by conventional thermal processing. Photo-induced deposition of low dielectric constant organic polymers for interlayer dielectrics has highlighted a significant role of photo effects on the curing of polyamic acid films. I-V measurements showed the leakage current density of the irradiated polymer films was over an order of magnitude smaller than has been obtained in the films prepared by thermal processing. Compared with conventional furnace processing, the photo-induced curing of the polyimide provided both reduced processing time and temperature, A new technique of low temperature photo-induced sol-gel process for the growth of low dielectric constant porous silicon dioxide thin films from TEOS sol-gel solutions with a 172 nm excimer lamp has also been successfully demonstrated. The dielectric constant values as low as 1.7 can be achieved at room temperature. The applications investigated so far clearly demonstrate that low cost high power excimer lamp systems can provide an interesting alternative to conventional UV lamps and excimer lasers for industrial large-scale low temperature materials processing.


ChemInform ◽  
2016 ◽  
Vol 47 (32) ◽  
Author(s):  
Mohamed Karmaoui ◽  
E. Venkata Ramana ◽  
David M. Tobaldi ◽  
Luc Lajaunie ◽  
Manuel P. Graca ◽  
...  

2000 ◽  
Vol 624 ◽  
Author(s):  
Ian W. Boyd ◽  
Jun-Ying Zhang

ABSTRACTIn this paper, UV-induced large area growth of high dielectric constant (Ta2O5, TiO2and PZT) and low dielectric constant (polyimide and porous silica) thin films by photo-CVD and sol-gel processing using excimer lamps, as well as the effect of low temperature UV annealing, are discussed. Ellipsometry, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), UV spectrophotometry, atomic force microscope (AFM), capacitance-voltage (C-V) and current-voltage (I-V) measurements have been employed to characterize oxide films grown and indicate them to be high quality layers. Leakage current densities as low as 9.0×10−8 A·cm−2and 1.95×10−7 A·cm−2at 0.5 MV/cm have been obtained for the as-grown Ta2O5 films formed by photo-induced sol-gel processing and photo-CVD, respectively – several orders of magnitude lower than for any other as-grown films prepared by any other technique. A subsequent low temperature (400°C) UV annealing step improves these to 2.0×10−9A·cm−2and 6.4×10−9A·cm−2, respectively. These values are essentially identical to those only previously formed for films annealed at temperatures between 600 and 1000°C. PZT thin films have also been deposited at low temperatures by photo-assisted decomposition of a PZT metal-organic sol-gel polymer using the 172 nm excimer lamp. Very low leakage current densities (10−7A·cm2) can be achieved, which compared with layers grown by conventional thermal processing. Photo-induced deposition of low dielectric constant organic polymers for interlayer dielectrics has highlighted a significant role of photo effects on the curing of polyamic acid films. I-V measurements showed the leakage current density of the irradiated polymer films was over an order of magnitude smaller than has been obtained in the films prepared by thermal processing. Compared with conventional furnace processing, the photo-induced curing of the polyimide provided both reduced processing time and temperature. A new technique of low temperature photo-induced sol-gel process for the growth of low dielectric constant porous silicon dioxide thin films from TEOS sol-gel solutions with a 172 nm excimer lamp has also been successfully demonstrated. The dielectric constant values as low as 1.7 can be achieved at room temperature. The applications investigated so far clearly demonstrate that low cost high power excimer lamp systems can provide an interesting alternative to conventional UV lamps and excimer lasers for industrial large-scale low temperature materials processing


2021 ◽  
Vol 1037 ◽  
pp. 167-173
Author(s):  
Natalia Yatsenko ◽  
Aleksandr I. Yatsenko ◽  
Natalia A. Vil'bitskaya ◽  
Olga I. Sazonova ◽  
Rimma V. Savanchuk

The post-sintering properties of walling high-calcium ceramics based on clay-containing raw materials in low-temperature roasting depend on the chemical-mineralogical composition of clay with different contents of iron, calcium-containing and alkaline oxides that contribute to the formation of new crystalline phases, which provide for the production of low-density ceramic material with high-strength properties.


2013 ◽  
Vol 24 (2) ◽  
pp. 170-172 ◽  
Author(s):  
Yong-Sen Sun ◽  
Ai-Ling Li ◽  
Fu-Jian Xu ◽  
Dong Qiu

2020 ◽  
Vol 120 ◽  
pp. 186-195
Author(s):  
E. S. Khomenko ◽  
E. V. Karasik

The results of glass binding obtaining in the Li2O — Al2O3 — SiO2 system for ceramic materials are presented in the article. The lithium aluminum silicate system was chosen taking into account the low temperature expansion coefficients of crystalline phases that form in it. This will allow controlling the thermal expansion of materials into which the glass binding will be introduced. A sol - gel method based on ethyl silicate and soluble salts of the corresponding oxides is proposed as a method for producing of glass binding. This method is more rational in comparison with the traditional method of glass melting due to low energy costs. Also, the method allows to obtain a more uniform and active product. The effect of glass binding on the properties of ceramic materials for various purposes has been investigated. As such materials, low-temperature electrotechnical porcelain, quartz ceramics, and engobe coatings were chosen. The glass binding was introduced into the raw material charge of these materials in an amount of 5 wt. %. Further, the properties of calcined product without additives and with additives under the same conditions were compared. The intense fluxing effect of glass binding during the formation of electrical porcelain has been established. The glass binding reinforces the effect of natural fluxes (pegmatites) that are present in the basic composition of the mass. This contributes to the material compaction during firing. The formation of eucryptite and spodumene helps to reduce the thermal expansion of material. The introduction of glass binding into the engobe led to a less intense compaction of its structure. This was observed due to an insufficient amount of the added glass binding for this type of material. In the composition of quartz ceramics, glass binding contributed to the material sintering, but the thermal properties were deteriorated. Thus, the sintering results of ceramic material with the introduction of glass binding in the charge composition are positive. However, sintering significantly depends on the material type. The glass binding stimulates the formation of a melt in which solid finely dispersed components of the ceramic mass dissolve. This contributes to the formation of a dense durable ceramic.


RSC Advances ◽  
2016 ◽  
Vol 6 (57) ◽  
pp. 51493-51502 ◽  
Author(s):  
Mohamed Karmaoui ◽  
E. Venkata Ramana ◽  
David M. Tobaldi ◽  
Luc Lajaunie ◽  
Manuel P. Graça ◽  
...  

Strontium hafnium oxide (SrHfO3) has great potential as a high-k gate dielectric material, for use in memories, capacitors, CMOS and MOSFETs.


2003 ◽  
Vol 769 ◽  
Author(s):  
C. K. Liu ◽  
P. L. Cheng ◽  
S. Y. Y. Leung ◽  
T. W. Law ◽  
D. C. C. Lam

AbstractCapacitors, resistors and inductors are surface mounted components on circuit boards, which occupy up to 70% of the circuit board area. For selected applications, these passives are packaged inside green ceramic tape substrates and sintered at temperatures over 700°C in a co-fired process. These high temperature processes are incompatible with organic substrates, and low temperature processes are needed if passives are to be embedded into organic substrates. A new high permeability dual-phase Nickel Zinc Ferrite (DP NZF) core fabricated using a low temperature sol-gel route was developed for use in embedded inductors in organic substrates. Crystalline NZF powder was added to the sol-gel precursor of NZF. The solution was deposited onto the substrates as thin films and heat-treated at different temperatures. The changes in the microstructures were characterized using XRD and SEM. Results showed that addition of NZF powder induced low temperature transformation of the sol-gel NZF phase to high permeability phase at 250°C, which is approximately 350°C lower than transformation temperature for pure NZF sol gel films. Electrical measurements of DP NZF cored two-layered spiral inductors indicated that the inductance increased by three times compared to inductors without the DP NZF cores. From microstructural observations, the increase is correlated with the changes in microstructural connectivity of the powder phase.


Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1738
Author(s):  
Saeid Vafaei ◽  
Alexander Wolosz ◽  
Catlin Ethridge ◽  
Udo Schnupf ◽  
Nagisa Hattori ◽  
...  

SnO2 nanoparticles are regarded as attractive, functional materials because of their versatile applications. SnO2 nanoaggregates with single-nanometer-scale lumpy surfaces provide opportunities to enhance hetero-material interfacial areas, leading to the performance improvement of materials and devices. For the first time, we demonstrate that SnO2 nanoaggregates with oxygen vacancies can be produced by a simple, low-temperature sol-gel approach combined with freeze-drying. We characterize the initiation of the low-temperature crystal growth of the obtained SnO2 nanoaggregates using high-resolution transmission electron microscopy (HRTEM). The results indicate that Sn (II) hydroxide precursors are converted into submicrometer-scale nanoaggregates consisting of uniform SnO2 spherical nanocrystals (2~5 nm in size). As the sol-gel reaction time increases, further crystallization is observed through the neighboring particles in a confined part of the aggregates, while the specific surface areas of the SnO2 samples increase concomitantly. In addition, X-ray photoelectron spectroscopy (XPS) measurements suggest that Sn (II) ions exist in the SnO2 samples when the reactions are stopped after a short time or when a relatively high concentration of Sn (II) is involved in the corresponding sol-gel reactions. Understanding this low-temperature growth of 3D SnO2 will provide new avenues for developing and producing high-performance, photofunctional nanomaterials via a cost-effective and scalable method.


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