Sol-Gel Processing of Glasses and Glass-Ceramics for Microelectronic Packaging

1991 ◽  
Vol 249 ◽  
Author(s):  
M.A. Sriram ◽  
P.N. Kumta
Keyword(s):  
Dielectric Constant ◽  
Thermal Analyses ◽  
Sol Gel ◽  
Glass Ceramics ◽  
Signal Propagation ◽  
Ceramic Materials ◽  
X Ray Diffraction ◽  
Low Dielectric ◽  
Heat Treated ◽  
Gel Processing

In recent years considerable progress has been made in electronic packaging substrate technology. The future need of miniaturization of devices to increase the signal processing speeds calls for an increase in the device density requiring the substrates to be designed for better thermal, mechanical and electrical efficiency.Fast signal propagation with minimum delay requires the substrate to possess very low dielectric constant. Several glasses and glass-ceramic materials have been identified over the years which show good promise as candidate substrate materials. Among these borophosphate and borophosphosilicate glass-ceramics have been recently identified to have the lowest dielectric constant (3.8). Sol-gel processing has been used to synthesize borosilicate, borophosphosilicate and borophosphate glasses and glass-ceramics using inexpensive boron oxide and phosphorus pentoxide precursors. Preliminary results of the processing of these gels and the effect of volatility of boron alkoxide and its modification on the gel structure are described. X-ray diffraction, Differential thermal analyses and FTIR have been used to characterize the as-prepared and heat treated gels.

Gel-derived amorphous cesium-aluminosilicate powders useful for formation of pollucite glass-ceramics

1991 ◽  
Vol 6 (2) ◽  
pp. 217-219 ◽  
Author(s):  
Mari A. Hogan ◽  
Subhash H. Risbud
Keyword(s):  
Electron Microscopy ◽  
Sol Gel ◽  
Glass Ceramics ◽  
Amorphous Powder ◽  
Glass Crystallization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Amorphous Powders ◽  
Gel Processing ◽  
Scanning Electron

Amorphous powders in the Cs2O–Al2O3−SiO2 system were prepared by sol-gel processing. Gels made from TEOS, Al-chelate, and Cs-acetate were dried and calcined to obtain molecularly mixed powders of analyzed compositions in the range useful for conversion to pollucite (CsAlSi2O6) glass-ceramics. X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetry (TG), and scanning electron microscopy (SEM) were used to characterize the powders. A typical amorphous powder of analyzed chemical composition (in wt.%) = 28.05Cs2O, 37.77SiO2, and 37.96Al2O3 was found to have a glass transition temperature of 945 °C and a glass crystallization temperature of 1026 °C. Preliminary experimental results of densification and crystallization of the amorphous powders show pollucite/mullite phases to be present.

Pentadionate: An Alternate Sol-Gel Method for the Synthesis of Ferroelectric Ba1−xSrxTiO3

1999 ◽  
Vol 606 ◽  
Author(s):  
Pramod K. Sharma ◽  
K. A. Jose ◽  
V. V. Varadan ◽  
V. K. Varadan
Keyword(s):  
Metal Oxides ◽  
Sol Gel ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
Barium Strontium ◽  
Transitional Metal ◽  
Heat Treated ◽  
Transitional Metal Oxides ◽  
Sol Gel Synthesis ◽  
Gel Processing

AbstractSol-gel synthesis of transitional metal oxides is one of the important technique to obtain the pure and homogenous materials at low temperature. In this work, Barium strontium titantate (BST) was synthesized by sol-gel processing using 2,4-pentadionate as the precursors of metal oxides. The Ba1−xSrxTiO3 was prepared for four values of x i.e. 0.2, 0.4, 0.5 and 0.6. The obtained powders were heated from 400 °C to 800 °C at the interval of 100 °C to determine the temperature of crystallization. The phase of the final products was investigated by x-ray diffraction (XRD). Two particle sizes (< 100 nm and 200-400 nm) were observed under the scanning electron microscope (SEM) of the heat treated xerogel. The dielectric properties were determined by impedance analyzer at the frequency of 1MHz and explained in detail for the different values of x.

Preparation, Dielectric and Magnetic Properties of Barium-Ferrite-Containing Microcrystalline Glass Ceramic by Citrate Sol-Gel Process

2007 ◽  
Vol 280-283 ◽  
pp. 457-460 ◽  
Author(s):  
Hai Jun Zhang ◽  
Xiao Lin Jia ◽  
Xi Yao ◽  
Liang Ying Zhang
Keyword(s):  
Dielectric Constant ◽  
Barium Ferrite ◽  
Sol Gel ◽  
Glass Ceramics ◽  
Complex Dielectric Constant ◽  
Complex Permeability ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sol Gel Process ◽  
Scanning Electron

Four kinds of barium-ferrite-containing microcrystalline glass ceramics, such as BaFe12O19/SiO2, BaFe12O19/SiO2-B2O3, BaFe12O19/SiO2-B2O3-K2O and BaFe12O19/SiO2-Al2O3-K2O were prepared by citrate sol-gel process, in which inceptive formation temperatures varied from 850°C to 1100°C. The complex dielectric constant and complex permeability of those glass ceramics were measured at 0.1-5.0GHz, and the frequency dependence of complex dielectric constant and permeability was studied. The microcrystalline glass ceramics were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM).

scholarly journals Sol-gel bioactive glass-ceramics Part II: Glass-ceramics in the CaO-SiO2-P2O5-MgO system

2009 ◽  
Vol 7 (3) ◽  
pp. 322-327 ◽  
Author(s):  
Lachezar Radev ◽  
Vladimir Hristov ◽  
Irena Michailova ◽  
Bisserka Samuneva
Keyword(s):  
Sol Gel ◽  
Glass Ceramics ◽  
Static Condition ◽  
Ceramic Materials ◽  
Molar Ratio ◽  
In Vitro Test ◽  
X Ray Diffraction ◽  
Vitro Test ◽  
Good Agreement

AbstractCeramics, with basic composition based on the CaO-SiO2-P2O5-MgO system with different Ca+ Mg/P+Si molar ratio (R), were prepared via polystep sol-gel technique. The structure of the obtained ceramic materials has been studied by XRD, FTIR spectroscopy, and SEM. X-ray diffraction showed the presence of akermanite and HA for the sample with R = 1.68 and Mg substituted β-TCP and silicocarnotite for the sample with R = 2.16, after thermal treatment at 1200°C/2 h. The obtained results are in good agreement with FTIR. In vitro test for bioactivity in static condition proved that the carbonate containing hydroxyapatite (CO3HA) can be formed on the surface of the synthesized samples. CO3HA consisted of both A- and B-type CO 32− ions. SEM micrographs depicted different forms of HA particles, precipitated on the surface after soaking in 1.5 simulated body fluid (SBF).

Photo-induced Large Area Growth Of Dielectrics With Excimer Lamps

2000 ◽  
Vol 617 ◽  
Author(s):  
Ian W. Boyd ◽  
Jun-Ying Zhang
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Low Temperature ◽  
Leakage Current ◽  
Sol Gel ◽  
Low Dielectric Constant ◽  
Large Area ◽  
Excimer Lamp ◽  
Low Dielectric ◽  
Current Densities

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.

Sol–gel deposited xerogel, aerogel and porogen based porous low-k thin films: A comparative investigation

2021 ◽  
pp. 2140019
Author(s):  
Swati Gupta ◽  
Anil Gaikwad ◽  
Ashok Mahajan ◽  
Lin Hongxiao ◽  
He Zhewei
Keyword(s):  
Dielectric Constant ◽  
Sol Gel ◽  
Comparative Investigation ◽  
Crosstalk Noise ◽  
Nanoelectronic Devices ◽  
Low Dielectric ◽  
Interconnect Delay ◽  
Xerogel Films ◽  
Low K ◽  
Porosity Percentage

Low dielectric constant (Low-[Formula: see text]) films are used as inter layer dielectric (ILD) in nanoelectronic devices to reduce interconnect delay, crosstalk noise and power consumption. Tailoring capability of porous low-[Formula: see text] films attracted more attention. Present work investigates comparative study of xerogel, aerogel and porogen based porous low-[Formula: see text] films. Deposition of SiO2 and incorporation of less polar bonds in film matrix is confirmed using Fourier Transform Infra-Red Spectroscopy (FTIR). Refractive indices (RI) of xerogel, aerogel and porogen based low-[Formula: see text] films observed to be as low as 1.25, 1.19 and 1.14, respectively. Higher porosity percentage of 69.46% is observed for porogen-based films while for shrinked xerogel films, it is lowered to 45.47%. Porous structure of low-[Formula: see text] films has been validated by using Field Emission Scanning Electron Microscopy (FE-SEM). The pore diameters of porogen based annealed samples were in the range of 3.53–25.50 nm. The dielectric constant ([Formula: see text]) obtained from RI for xerogel, aerogel and porogen based films are 2.58, 2.20 and 1.88, respectively.

Stress Development in Low Dielectric Constant Silica Films During Drying and Heating Process

1999 ◽  
Vol 594 ◽  
Author(s):  
Mengcheng Lu ◽  
C. Jeffrey Brinker
Keyword(s):  
Dielectric Constant ◽  
Tensile Stress ◽  
Sol Gel ◽  
Low Dielectric Constant ◽  
Heating Process ◽  
Residual Tensile Stress ◽  
Silica Films ◽  
Stress Development ◽  
Low Dielectric

AbstractLow dielectric constant silica films are made using a surfactant templated sol-gel process (K∼2.5) or an ambient temperature and pressure aerogel process (K∼1.5). This paper will present the in-situ measurement and analysis of stress development during the making of these films, from the onset of drying till the end of heating. The drying stress is measured by a cantilever beam technique; the thermal stress is measured by monitoring the wafer curvature using a laser deflection method. During the course of drying, the surfactant templated films experience a low drying stress due to the influence of the surfactant on surface tension and extent of siloxane condensation. The aerogel films first develop a biaxial tensile stress due to solidification and initial drying. At the final stage of drying where the drying stress vanishes, dilation of the film recreates the porosity of the wet gel state, reducing the residual stress to zero. For the surfactant templated films, very small residual tensile stress remains after the heat treatment is finished (∼30MPa). Aerogel film has almost no measurable stress developed in the calcination process. In situ spectroscopic ellipsometry analysis during drying and heating, and TGA/DTA are all used to help understand the stress development.

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