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Synthesis of Oxide Thin Films on Silicon Substrate using Supercritical Carbon Dioxide Fluid Fuyuki Kano, Hiroshi Uchida, Kazuko Sugimoto and Seiichiro Koda Department of Chemistry, Faculty of Science and Technology, Sophia University 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554, Japan Keywords: supercritical fluid, carbon dioxide, titanium oxide, silicon wafer ABSTRACT Thin films of titanium oxide (TiO2) were synthesized from Titanium diisopropoxide bis(dipivaloylmethanate) [Ti(O-i-Pr)2(dpm)2] as a source material using supercritical carbon dioxide (CO2) fluid.
For achieving advanced integration of memory devices, the techniques for oxide film deposition have to satisfy some requests like (1) conformal deposition on the substrate with complicated structure such as nano-trench and hole units, (2) selective control of chemical composition for multicomponent films, and (3) crystallization at lower temperatures to avoid the oxidation of Si surface, etc.
However, the conventional film-deposition techniques have hardly satisfied these demands simultaneously; for instance, chemical vapor deposition (CVD) process enables to deposit uniform films of organized complicated structure whereas it still has difficulty in controlling the individual amount of source supply which determines the chemical composition of the resultant multicomponent films.
The present authors consider that the material characteristics, such as microstructure and crystal structure, of the products using SCFD process would be influenced significantly by the temperature and/or pressure of the supercritical fluid, because the physical properties of the fluid vary greatly according to these parameters.
In this study, therefore, the influence of the various parameters for the supercritical CO2 fluid on the structure of the resulting oxide films by SCFD process was investigated.

Studies of Asymmetric Hysteresis Loops and Leakage Current Behaviors in Pt/Al2O3/SiO2/Si /PZT/Au Structures Prepared by MOCVD Method Masruroh1,a, Masayuki TODA2,b 1Physics Department, Faculty of Mathematics & Natural Science, Brawijaya University, Malang, Indonesia 2Department of Chemistry and Chemical Engineering, Yamagata University, Yonezawa-Yamagata 992-8510 * WACOM R&D CO., LTD, 568 TANAKA, Fukaya shi, Saitama 369-1108, Japan arafizen_02@yahoo.com, bmasa-t@ivory.plala.or.jp Keywords: PZT films, Pt bottom electrode, Au top electrode, different work function, asymmetries Abstract.
Properties of PZT film depend on many parameters including composition, crystal structure, substrate films, film thickness and electrodes.
The generated substrate structure was Pt/Al2O3/SiO2/Si(100).
The top electrode structures were patterned with circles using a shadow mask with a diameter of 100 mm.
Illustration model of Pt/PZT/Au structure with a different top and bottom electrode and work function; when drive applied to Pt (left) and drive applied to Au (right)

China aqixu2007@126.com, bfengdaolun@aliyun.com Keywords: TiO2 nanotube structure, Anodization, Granulation, Microwave-assisted annealing, Photocatalytic activity Abstract.
In contrast, the top and side SEM image of TNs without annealing are presented in Fig. 1D, and their structure show no difference from the results obtained elsewhere [17].
Occasionally, Cracking of TNs, and relative mild granulation without destroying the tube structure is also observed.
Schmuki, European Journal of Inorganic Chemistry 2010 (2010) 4351-4356

The results show that the alloy mainly contains hexagonal structure MgZn2 and tetragonal structure Al2CeZn2 precipitates.
Al has a cubic structure (a=b=c=4.0497Å，α=β=γ=90°), Al2CeZn2 phase has a tetragonal structure (a=b=4.25Å，c=11.02Å，α=β=γ=90°), and MgZn2 phase has a hexagonal structure (a=b=5.223, c=8.569, α=β=90°, γ=120°).
Electroanalytical Chemistry, 2007 (585): 220-229

The unique capabilities of atom probe tomography (APT) to characterize internal interfaces and layer chemistry with sub-nanometer scale resolution in three dimensions have been recently opened up to materials with poor electrical conductivity by the use of ultrafast laser pulses.
This low value of the solubility is limited by the fact that Ni2Si and Pt2Si crystallographic structures are different (respectively orthorhombic and rhombohedral).

The structure of ionic liquid was characterized by IR, 1HNMR and quantum chemical calculations.
Their negligible vapor pressure, excellent thermal stabilities and their polar and non-coordinating properties, especially the provision of a simple and effective method of recovering products and recycling catalysts have made them solvents of choice for green chemistry[1-5].
The number of imaginary vibrational frequencies (NImag) was determined if the optimized structures were local minima or higher-order saddle points.
However, the large volume and the heptagon structure of caprolactam made it large steric hindrance to form four H bonds.
It was in agreement with the structures.

It is shown that the introduction of limestone waste contributes to changing the nature of crystallization and structure formation of cement stone.
When creating construction composites, on the basis of Portland cement in particular a significant attention is paid to the creation of an optimal dense structure of the hardened composition.
Also an effective way of compacting the structure of cement composites is the use of fine mineral fillers [1-5].
It can be due to the effective compaction of the cement stone structure by waste particles and ensuring a more complete flow of the processes of cement hydration in their presence.
Kurdowski, Mineral Additions for Cement Production, in: Cement and Concrete Chemistry.

It was applied to calculating mono-vacancy formation energy, divacancy binding energy, elastic constants, energy difference of different structures, the surface energy, and the phonon spectra of iron and europium.
r/r1e Eu Fe Fig.1 Pair potentials of Fe-Fe, Eu-Eu Fig. 2 Electron density distribution and Fe-Eu functions of Fe and Eu 1.75 2.00 2.25 2.50 2.75 3.00 3.25 3.50 -5 -4 -3 -2 -1 0 1 2 E(r) /eV r /angstrom present Rose Fe 2.5 3.0 3.5 4.0 4.5 5.0 5.5 -2 -1 0 1 2 E(r) /eV r /angstrom Present Rose Eu Fig. 3 Comparison of total energy of Fe and Eu between the present model and Rose's equation 3 Results and discussion The calculated elastic constants, energy differences between different structures, and surface energies of low index are given in Table 2.
The structural energy differences between BCC structure and FCC, HCP, SC structures calculated with the present model are reasonable.
The BCC structure is the most stable structure.
Eyring, Handbook on the physics and chemistry of rare earths, Vol 8, (North-Holland, Amsterdam 1986) [16] C.

Synthesis of Hydrophobic Modified Polyacrylamide Functional Materials in Supercritical CO2 Lan Zheng1, a*, Yuqi Wang 1,b and Yin Dang2,c 1 School of Chemical Engineering, Northwest University, Xi’an, China 2 School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guang Zhou, China a lanny@nwu.edu.cn, bwangyuqi@nwu.edu.cn, cdangyinjupiter@yahoo.com.cn Keywords: supercritical CO2; polyacrylamide; copolymerization; hydrophobic associating.
The functional fluoride hydrophobic associating polymer products have some special characters with excellent performance of gas storage The structure of the copolymer products was characterized by FTIR, MR, 1H-NMR and SEM analysis..
Structure analysis of copolymer .
The monomer ratio in the copolymer is the possible structure of the copolymer is approximate consistent to the the molar ratio of feed.
The structure of the copolymer was characterized by FTIR, 1H-NMR, MS and SEM.

The products maintain perfect flower-like structure when Ce:ZnO (molar ratio) is 0.5%.
But effects of Ce doped ZnO on its structure especially on absorbing properties are rarely reported [8-11].
ZnO remains flower like structure basicallywith Ce doping concentration is 0.5% [Fig. 2(a)].
It has been found that the structure of Ce doped ZnO composite and pure ZnO is consistent.
Materials Chemistry and Physics, 2003,66: 568~570