Iron-Silicate Glassy Films by Sol-Gel Conversion Induced by Rapid Thermal Processing

ABSTRACTThe sol-gel system iron triethoxide - tetraethylorthosilicate (TEOS) with the Fe/Si atomic ratio ranging from 0 to 1 has been investigated. Our study leads to the conclusion that the annealing method of the hydrolyzed precursor film determines the type of solid film formed. Annealing by Rapid Thermal Processing (RTP) with its high heating and cooling rates yields amorphous, glassy iron silicate films. These films result from polycondensation reactions between Si-OH and Fe-OH groups of the hydrolyzed precursors forming Fe-O-Si and Si-O-Si bonds. These bonds show a characteristic vibration band in FTIR spectra, which is most intense for Fe/Si = 1, and shifts for increasing Fe/Si ratio from 1073 down to 965 cm-1.The iron silicate film with Fe/Si =1 obtained by RTP displays an optical absorption band around 320 nm, which indicates that Fe3+-ions have a tetrahedral coordination similar to the Si4+-ions in Si02 and glass with tetrahedrally coordinated silicon and iron ions linked by bridging oxygen atoms. The films, typically 0.1 μm thick, annealed by RTP have a smooth, mechanically hard surface. This glassy structure can be formally presented as FeSiOx. Conventional furnace heating with low heating/cooling rates yields nanocrystalline films with predominantly Si-O-Si bonding in grains with sizes below 40 nm. More structural and chemical investigation is needed to elucidate the details of the structure and the formation mechanism of the amorphous compound, but we can conclude that the cooling rate has a direct effect on the degree of non-crystallinity of the compound. The high cooling rate of RTP will retain the Fe-O-Si bonds formed in a state of inequilibrium, and “quench” them in an amorphous, metastable glass compound, whereas slow cooling gives rise to nanocomposite film formation.

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Rapid thermal processing of zirconia thin films produced by the sol‐gel method

Journal of Applied Physics ◽

10.1063/1.350333 ◽

1991 ◽

Vol 70 (4) ◽

pp. 2348-2352 ◽

Cited By ~ 21

Author(s):

R. Pascual ◽

M. Sayer ◽

C. V. R. Vasant Kumar ◽

Lichun Zou

Keyword(s):

Thin Films ◽

Thermal Processing ◽

Sol Gel ◽

Rapid Thermal Processing ◽

Gel Method ◽

Sol Gel Method

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Novel Multilayer Process for CuInSe2 Thin Film Formation by Rapid Thermal Processing

MRS Proceedings ◽

10.1557/proc-485-163 ◽

1997 ◽

Vol 485 ◽

Cited By ~ 2

Author(s):

Chih-hung Chang ◽

Billy Stanbery ◽

Augusto Morrone ◽

Albert Davydov ◽

Tim Anderson

Keyword(s):

Thermal Processing ◽

Physical Vapor Deposition ◽

Film Formation ◽

Rapid Thermal Processing ◽

Precursor Film ◽

Bilayer Structure ◽

X Ray Diffraction ◽

X Ray ◽

Deposition Parameters ◽

Cuinse2 Thin Film

AbstractCuInSe2 thin films have been synthesized from binary precursors by Rapid Thermal Processing (RTP) at a set-point temperature of 290°C for 70 s. With appropriate processing conditions no detrimental Cu2-xSe phase was detected in the CIS films. The novel binary precursor approach consisted of a bilayer structure of In-Se and Cu-Se compounds. This bilayer structure was deposited by migration enhanced physical vapor deposition at a low temperature (200°C) and the influence of deposition parameters on the precursor film composition was determined. The bilayer structure was then processed by RTP and characterized for constitution by X-ray diffraction and for composition by Wavelength Dispersive X-ray Spectroscopy.

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Rapid Thermal Processing of Ferroelectric Thin Films

MRS Proceedings ◽

10.1557/proc-224-305 ◽

1991 ◽

Vol 224 ◽

Cited By ~ 10

Author(s):

Zheng Wu ◽

Roberto Pascual ◽

C.V.R. Vasant Kumar ◽

David Amd ◽

Michael Sayer

Keyword(s):

Thin Films ◽

Lead Zirconate Titanate ◽

Thermal Processing ◽

Crystallization Behavior ◽

Sol Gel ◽

Rapid Thermal Processing ◽

Lead Zirconate ◽

Dielectric Constants ◽

Heating Rates ◽

Pzt Films

AbstractThe preparation of ferroelectric lead zirconate titanate (PZT) thin films by rapid thermal processing (RTP) is reported. The films were deposited by chemical sol gel and physical sputter techniques. The heating rate of RTP was found to have significant influence on the crystallization behavior. Faster heating rates lead to lowering of the crystallization temperature and reduction of grain size. PZT films were obtained with dielectric constants ~ 1000, remanent polarizations between 20 and 30μC/cm2, coercive fields 20 to 60kV/cm, and no significant fatigue for 109 to 1010 stressing cycles.

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Chemical and Structural Evolution of Sol-Gel-Derived Hydroxyapatite Thin Films under Rapid Thermal Processing

Journal of the American Ceramic Society ◽

10.1111/j.1151-2916.1996.tb08514.x ◽

1996 ◽

Vol 79 (4) ◽

pp. 837-842 ◽

Cited By ~ 57

Author(s):

Stephen W. Russell ◽

Karen A. Luptak ◽

Carlos Tres A. Suchicital ◽

Terry L. Alford ◽

Vincent B. Pizziconi

Keyword(s):

Thin Films ◽

Thermal Processing ◽

Sol Gel ◽

Rapid Thermal Processing ◽

Structural Evolution

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Thermal stress, cooling-rate and fictive temperature of silicate melts

Contributions to Mineralogy and Petrology ◽

10.1007/s00410-021-01836-y ◽

2021 ◽

Vol 176 (10) ◽

Author(s):

Sharon L. Webb

Keyword(s):

Heat Capacity ◽

Cooling Rate ◽

Heating Rate ◽

Calibration Curve ◽

Silicate Melts ◽

Internal Stresses ◽

Heating Rates ◽

Fictive Temperature ◽

Slow Cooling ◽

Cooling Rates

AbstractThe unknown cooling-rate history of natural silicate melts can be investigated using differential scanning heat capacity measurements together with the limiting fictive temperature analysis calculation. There are a range of processes occurring during cooling and re-heating of natural samples which influence the calculation of the limiting fictive temperature and, therefore, the calculated cooling-rate of the sample. These processes occur at the extremes of slow cooling and fast quenching. The annealing of a sample at a temperature below the glass transition temperature upon cooling results in the subsequent determination of cooling-rates which are up to orders of magnitude too low. In contrast, the internal stresses associated with the faster cooling of obsidian in air result in an added exothermic signal in the heat capacity trace which results in an overestimation of cooling-rate. To calculate cooling-rate of glass using the fictive temperature method, it is necessary to create a calibration curve determined using known cooling- and heating-rates. The calculated unknown cooling-rate of the sample is affected by the magnitude of mismatch between the original cooling-rate and the laboratory heating-rate when using the matched cooling-/heating-rate method to derive a fictive temperature/cooling-rate calibration curve. Cooling-rates slower than the laboratory heating-rate will be overestimated, while cooling-rates faster than the laboratory heating-rate are underestimated. Each of these sources of error in the calculation of cooling-rate of glass materials—annealing, stress release and matched cooling/heating-rate calibration—can affect the calculated cooling-rate by factor of 10 or more.

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116 IMPROVED SURVIVAL BY CRYOPRESERVING RHESUS MACAQUE (MACACA MULATTA) SPERMATOZOA WITH DIRECTIONAL FREEZING TECHNIQUE

Reproduction Fertility and Development ◽

10.1071/rdv22n1ab116 ◽

2010 ◽

Vol 22 (1) ◽

pp. 217 ◽

Cited By ~ 5

Author(s):

W. Si ◽

Y. Lu ◽

X. He ◽

S. Ji ◽

Y. Niu ◽

...

Keyword(s):

Rhesus Monkey ◽

Cooling Rate ◽

Sperm Motility ◽

Genetically Engineered ◽

Human Diseases ◽

Slow Cooling ◽

Cooling Rates ◽

Important Species ◽

Directional Freezing ◽

Acrosomal Integrity

A significant increase in nonhuman primate models of human diseases will be expected in the near future since the successes in production of genetically engineered rhesus monkey models of human diseases. Sperm banking can provide an effective way to preserve valuable genetic resources. Our objective was to (1) develop a protocol using directional freezing technique (DFT) for rhesus monkey spermatozoa cryopreservation, which allows precise control of the velocity and the morphology of the ice-front propagation by transferring the tubes loaded with 2 mL sperm samples at a controllable velocity through two separate chambers with controllable temperature settings, and (2) achieve survival rate that was higher than that achieved with conventional freezing technique (CFT), by which sperm samples were cryopreserved in 0.25 mL straws with liquid nitrogen vapor in a styrofoam box. Sperm motility, acrosomal integrity, and in vitro fertilization (IVF) assay were used to assess the function of frozen-thawed spermatozoa. Data were analyzed by ANOVA and Fisher protected LSD test. Experiment 1 was aimed at optimizing the cooling rate using DFT. Tubes were frozen using the multi-thermal gradient freezing device (MTG 516, Harmony CryoCareTM, IMT Ltd.) at fast (16°C/min), medium (12°C/min), and slow (7°C/min) cooling rates, which corresponded to the transferring velocities (2.5, 1.5, and 0.5 mm s-1, respectively). The results showed that spermatozoa frozen at fast and medium cooling rates showed significantly higher frozen-thawed motility than those frozen at slow cooling rate (61% and 59% v. 50%, P < 0.05). However, no difference was observed on sperm acrosomal integrity among the experimental groups (84, 80, and 78%, respectively, P > 0.05). The purposes of Experiment 2 were determined to examine if using DFT at the optimized cooling rate (12°C/min) can improve the cryo-survival of rhesus monkey spermatozoa compared with CFT. Our results showed that spermatozoa cryopreserved by using DFT achieved significantly higher frozen-thawed sperm motility that those cryopreserved by using CFT (64 v. 54%, P < 0.05). However, no difference was observed on acrosomal integrity between spermatozoa cryopreserved by DFT and CFT (84 and 83%, respectively; P > 0.05). The function of spermatozoa cryopreserved by using DFT was further evaluated by IVF. Females were treated with rhFSH twice-daily for 8 days after the onset of menses and following a treatment of hCG injection on Day 9. Cumulus-oocyte complexes were collected by laparoscopic follicular aspiration 32 h later. Of the inseminated oocytes, 79% were fertilized and 90 and 53% of the resulting zygotes developed into 2-cell and blastocysts, respectively. The fertilization rate was lower and the blastocyst rate was slightly higher than our previous report when fresh spermatozoa were used for IVF (94 and 52%, respectively). Our results indicate that spermatozoa of rhesus monkeys can be effectively cryopreserved using DFT in large volume. This finding provided a new and effective way for genetics preservation purposes in this important species.

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Influence of Cooling Rates on Phase Transitions of Bent-Core Liquid Crystal 1,3-Phenylene-bis[4-(hexylcarboyloxyl)benzylideneamine]

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.428-429.247 ◽

2010 ◽

Vol 428-429 ◽

pp. 247-250 ◽

Cited By ~ 1

Author(s):

Yuan Ming Huang ◽

Qing Lan Ma ◽

Bao Gai Zhai

Keyword(s):

Differential Scanning Calorimetry ◽

Phase Transitions ◽

Liquid Crystal ◽

Optical Microscopy ◽

Cooling Rate ◽

Scanning Calorimetry ◽

Slow Cooling ◽

Cooling Rates ◽

Polarized Optical Microscopy ◽

Fast Cooling

The influence of cooling rate on the phase transitions of a three-benzene-ring containing bent-core liquid crystal 1,3-phenylene-bis[4-(hexylcarboyloxyl)benzylideneamine] has been investigated by means of differential scanning calorimetry and polarized optical microscopy. Our results show that the cooling rates in the second cooling run pose significant effects on the phase transitions of the bent-core liquid crystal despite the cooling rates in the first cooling run pose little effects on the phase transitions. In the second cooling run, the banana phases survived only when the cooling rates were in the range of 14~15oC/min whereas both slow cooling rates which were less than 13oC/min and fast cooling rates which were higher than 16oC/min made the banana phases disappeared.

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Rapid thermal processing of lithium tantalite thin films prepared by a diol-based sol–gel process

Applied Physics A ◽

10.1007/s00339-003-2493-x ◽

2004 ◽

Vol 79 (1) ◽

pp. 103-108 ◽

Cited By ~ 9

Author(s):

M.C. Kao ◽

H.Z. Chen ◽

C.M. Wang ◽

Y.C. Chen ◽

M.S. Lee

Keyword(s):

Thin Films ◽

Thermal Processing ◽

Sol Gel ◽

Rapid Thermal Processing ◽

Sol Gel Process

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Achieving the Dual Phase Structure in Low Alloyed Steel with Slow Cooling Rate

Materials Science Forum ◽

10.4028/www.scientific.net/msf.575-578.1117 ◽

2008 ◽

Vol 575-578 ◽

pp. 1117-1122

Author(s):

Tarja Jäppinen ◽

Seppo Kivivuori

Keyword(s):

Cooling Rate ◽

Phase Structure ◽

Steel Wire ◽

Optical Microscope ◽

Carbon Steels ◽

Alloying Elements ◽

Dual Phase ◽

Low Carbon ◽

Slow Cooling ◽

Cooling Rates

In steel wire processing it is difficult to reach a homogenous structure throughout the cross-section of the wire particularly in greater diameters. One alternative for producing a homogenous structure is to find a cooling path with a wide transformation temperature range. Fully austenite steel wire rolled at high temperatures can be decomposed into ferritic-martensitic dual phase structure using relatively slow cooling rates. Test materials were low alloyed low carbon steels with variations in alloying elements. Gleeble-1500 thermomechanical simulator was utilised to study the effect of cooling rate on decomposition of austenite after deformation. The microstructures were studied with an optical microscope. In certain low alloyed steels slow cooling rates eliminate the bainite transformation and instead martensite is formed. The final microstructure depends mainly on the carbon content but also on the amount of other alloying elements and their effects on the austenite phase.

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Rapid Thermal Processing and Properties of Sol-Gel Derived Ferroelectric Thin-Films for Non-Volatile Memories.

MRS Proceedings ◽

10.1557/proc-224-311 ◽

1991 ◽

Vol 224 ◽

Cited By ~ 3

Author(s):

C. K. Barlingay ◽

S. K Dey

Keyword(s):

Thin Films ◽

Thermal Processing ◽

High Field ◽

Growth Habit ◽

Sol Gel ◽

Rapid Thermal Processing ◽

Field Measurements ◽

Ferroelectric Thin Films ◽

Columnar Growth ◽

Ferroelectric Switching

AbstractFerroelectric Pb(Zr0.52Ti0.48)O3 or PZT (52/48) thin-films (0.5 μm) were integrated onto Pt passivated Si wafers (3–4 inches) by polymeric solgel processing followed by rapid thermal annealing. Dense and crack-free perovskite microstructures were obtained by densification of the amorphous gel-matrix prior to crystallization. The films exhibited submicron grains (0.2–0.6 μm) with a columnar growth habit. High field measurements on thin-films determined Pr, Psp, and Ec in the ranges of 29–32 μC/cm2. 44–58 μC/cm2, and 50–60 kV/cm, respectively, and ferroelectric switching times below 3 ns.

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