• Journal of the Korean institute of surface engineering
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• v.46 no.2
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• pp.55-60
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• 2013

Superhard TiN coatings were fabricated by DC and ICP (inductively coupled plasma) assisted magnetron sputtering techniques. The effect of ICP power, ranging from 0 to 300 W, on coating microstructure, preferred orientation mechanical properties were systematically investigated with HR-XRD, SEM, AFM and nanoindentation. The results show that ICP power has a significant influence on coating microstructure and mechanical properties of TiN coatings. With the increasing of ICP power, coating microstructure evolves from the columnar structure of DC process to a highly dense one. Grain sizes of TiN coatings were decreased from 12.6 nm to 8.7 nm with increase of ICP power. The maximum nanohardness of 67.6 GPa was obtained for the coatings deposited at ICP power of 300 W. Preferred orientation in TiN coatings also vary with ICP power, exerting an effective influence on film nanohardness.

• The Journal of the Petrological Society of Korea
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• v.3 no.1
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• pp.20-33
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• 1994

Some of the seven types of subgrain boundaries (Means and Ree, 1988) in octachloropropane samples show distinctive deformation patterns during their development. Type II subgrain boundaries migrate to accommodate the deformation difference between adjacent grains. The formation of Type III requires a rigid-body roation of grains to reduce misorientation of adjacent grains. Type I, IV, V and VI develop either in static or dynamic condition. Type VII form only in static environments after deformation. Ribbon grains can develop via Type III or Type IV process. The orientation pattern and density of subgrain boundaries are more or less stable through a post-deformation heating. Subgrain boundary orientations are symmetric with respect to the grain-shape foliation in pure shear. In simple shear, their maximum inclines toward the direction of shear.

• Korean Journal of Crystallography
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• v.12 no.4
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• pp.233-238
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• 2001

X-ray microdiffraction which uses x-ray beam focused down to a micron size from synchrotron radiation sources allow precision measurements of local orientation and strain variations in polycrystalline materials. Using x-ray microdiffraction setup at Pohang Light Source, we investigated the tex-ture of Cu interconnects with various widths on Si wafer by collecting Laue images and focused to about 2×3㎛ ² in size. Our results show that 1㎛ wide Cu interconnect had grains in rather ran- dom orientation. On the other hand the 20㎛ wide interconnects showed a 〈111〉fiber texture near the center. The grains were 2∼5㎛ long at the 1㎛ wide interconnect and 6∼8㎛ in size at the 20㎛ wide interconnect.

• Journal of the Korean Ceramic Society
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• v.49 no.6
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• pp.556-560
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• 2012

Nanocrystalline CrN coatings were deposited by DC and ICP-assisted magnetron sputtering on Si (100) substrates. The influences of the ICP power on the microstructural and crystallographic properties of the coatings were investigated. For the generation of the ICP, radio frequency was applied using a dielectric-encapsulated coil antenna installed inside the deposition chamber. As the ICP power increased from 0 to 500W, the crystalline grain size decreased. It is believed that the decrease in the crystal grain size at higher ICP powers is due to resputtering of the coatings as a result of ion bombardment as well as film densification. The preferential orientation of CrN coatings changed from (111) to (200) with an increase in the ICP power. The ICP magnetron sputtering CrN coatings showed excellent surface roughness compared to the DC magnetron sputtering coatings.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.4052-4059
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• 2021

The microstructure of the fuel pellet plays an essential role in fission gas buildup and release and is critical for the safe and continued operation of nuclear power stations. Structural analysis of uranium dioxide (UO₂)-molybdenum (Mo) composite fuel pellets prepared at a range of sintering temperatures from 1300 to 1800 ℃ was performed. Mo micro and nanoparticles were used in making the composite pellets. A systematic investigation into the influence of processing parameters during Spark Plasma Sintering (SPS) of the pellets on the microstructure, texture, grain size, and grain boundary characters of UO₂-Mo is presented. UO₂-Mo composite show significant differences in the fraction of general boundaries and also special/coincident site lattice (CSL) boundaries. EBSD orientation maps demonstrated that <111> texturing was observed in the pellets fabricated at 1500 ℃. The experimental investigations suggest that UO₂-Mo composite pellets have favorable microstructural features compared to the UO₂ pellet.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.1
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• pp.26-35
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• 2024

Aluminum-induced crystallization (AIC) as a route to reduce the fabrication cost and to obtain polycrystalline Si (p-Si) thin-film of large grain size is a promising alternative of single-crystalline (s-Si) substrate or p-Si thin-film obtained by conventional methods such as solid phase crystallization (SPC) and laser-induced crystallization (LIC). As the AIC process occurs at the interface between a-Si and Al thin-films, there are various process and interface parameters. Also, it directly means that there is a certain parametric window to obtain p-Si of large grain size having uniform crystal orientation. In this article, we investigate the effect of the various process and interface parameters to obtain p-Si of large grain size and uniform crystal orientation from the literature review. We also suggest the potential use of the p-Si as a virtual substrate for the growth of various compound semiconductors in a form of low-dimension as well as thin-film as a way for their monolithic integration on Si.

• Korean Journal of Materials Research
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• v.22 no.4
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• pp.190-194
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• 2012

The formation of high-quality polycrystalline silicon (poly-Si) on relatively low cost substrate has been an important issue in the development of thin film solar cells. Poly-Si seed layers were fabricated by an inverse aluminum-induced crystallization (I-AIC) process and the properties of the resulting layer were characterized. The I-AIC process has an advantage of being able to continue the epitaxial growth without an Al layer removing process. An amorphous Si precursor layer was deposited on Corning glass substrates by RF magnetron sputtering system with Ar plasma. Then, Al thin film was deposited by thermal evaporation. An $SiO_2$ diffusion barrier layer was formed between Si and Al layers to control the surface orientation of seed layer. The crystallinity of the poly-Si seed layer was analyzed by Raman spectroscopy and x-ray diffraction (XRD). The grain size and orientation of the poly-Si seed layer were determined by electron back scattering diffraction (EBSD) method. The prepared poly-Si seed layer showed high volume fraction of crystalline Si and <100> orientation. The diffusion barrier layer and processing temperature significantly affected the grain size and orientation of the poly Si seed layer. The shorter oxidation time and lower processing temperature led to a better orientation of the poly-Si seed layer. This study presents the formation mechanism of a poly seed layer by inverse aluminum-induced crystallization.

• Proceedings of the Korean Ceranic Society Conference
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• 2000.04a
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• pp.22.1-22.1
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• 2000

• Nuclear Engineering and Technology
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• v.6 no.4
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• pp.219-230
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• 1974

The previous expression for the diffracted neutron intensity by a highly oriented polycrystalline is modified using the Kunitomi's formula of the crystal reflectivity The method of studying the preferred orientation in metals with white neutron is proposed utilizing the above formula and the fact that the real position of the diffraction of certain grain in the sample can be found by the comparison of the smaller angle part of the maxwellian curve of the calculated intensity of neutrons diffracted and the experimenal curves. The most probable wavelength of thermal neutrons from the reactor is found by the measurement of the neutron spectrum with the correction for the crystal about the multiple reflection and the absorption of neutrons and turned out to be 1.025 $\pm$ 0.001$\AA$. The preferred orientations of some electric steel sheets, mostly with the cube-on-face orientations, are investigated by the present method. The orientations of most grains relative to the rolling directions are found to be within 5 degrees. It is found the most of theories for large crystals may be extended to highly oriented polycrystalline materials without extensive modification.

• Corrosion Science and Technology
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• v.16 no.1
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• pp.1-7
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• 2017

When aiming for an increased and more sustainable use of metals a thorough knowledge of the corrosion phenomenon as function of the local metal microstructure is of crucial importance. In this work, we summarize the information presented in our previous publications[1-3] and present an overview of the different local (electrochemical) techniques that have been proven to be effective in studying the relation between different microstructural variables and their different electrochemical behavior. Atomic force microscopy (AFM)[1], scanning electrochemical microscopy (SECM)[2], and electrochemical scanning tunneling microscopy (EC-STM)[3] were used in combination with electron backscatter diffraction (EBSD). Consequently, correlations could be identified between the grain orientation and grain boundary characteristics, on the one hand, and the electrochemical behavior on the other hand. The grain orientation itself has an influence on the corrosion, and the orientation of the neighboring grains also seems to play a decisive role in the dissolution rate. With respect to intergranular corrosion, only coherent twin boundaries seem to be resistant.