• Journal of the Korean Vacuum Society
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• v.9 no.2
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• pp.99-101
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• 2000

The fabrication of the submicron size hole has been interesting due to the potential application of the near field optical sensor or liquid metal ion source. The 2 micron size dot array was photolithographically patterned. After formation of the V-groove shape by anisotropic KOH etching, dry oxidation at $1000^{\circ}C$ for 600 minutes was followed. In this procedure, the orientation dependent oxide growth was performed to have an etch-mask for dry etching. The reactive ion etching by the inductively coupled plasma (ICP) system was performed in order to etch ~90 nm $SiO_2$ layer at the bottom of the V-groove and to etch the Si at the bottom. The negative ion energy would enhance the anisotropic etching by the $Cl_2$ gas. After etching, the remaining thickness of the oxide on the Si(111) surface was measured to be ~130 nm by scanning electron microscopy. The etched Si aperture can be used for NSOM sensor.

• Korean Journal of Materials Research
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• v.3 no.2
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• pp.158-165
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• 1993

Abstract To investigate the effect of underlying Si on the thermal stability of the TiS$i_2$ film, TiS$i_2$ films obtained by the solid-state reaction of the Ti film on as-deposited or on heat-treated poly-silicon and amorphous-silicon were annealed at 90$0^{\circ}C$ for various times. The poly-Si film was evaluated by XRD, SEM and TEM. The thermal stability of the TiS$i_2$ film was evaluated by measuring the sheet resistance and microstructural evolution during furnace annealing. Agglomeration of the TiSi, film occurred more on amorphous-Si than on poly-Si. The thermal stability of the TiS$i_2$ film was improved by annealing poly-Si. The Si layer crystallized from amorphous-Si has an equiaxed structure with the (111) preferred orientation whereas for as-deposited poly-Si has a columnar structure with the (110) orientation. Better thermal stability of the TiS$i_2$ film can be obtained by the higher surface energy of underlying poly-Si.

• Proceedings of the Korean Vacuum Society Conference
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• 1996.06a
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• pp.97-97
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• 1996

• Proceedings of the Korean Vacuum Society Conference
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• 2002.02a
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• pp.115-115
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• 2002

• Korean Journal of Materials Research
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• v.3 no.4
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• pp.403-409
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• 1993

In this paper, an $NH_3$, added during dry oxidation and annealing m Si( 111) is clarified effect ive to suppress or remove defects. Annealing effects in $N_2$ and $NH_3/N_2$ ambient are estimated with dry $O_2$ and $NH_4$ oxidation($NH_3$ added in dry $O_2$ oxidation) method. C;em'rated defects in dry $O_2$ oxidation are lengthened according to oxidation time. but any defects in $NH_3$ oxidation are not found. Dry oxidation, after $NH_3$ oxidation as an initial oxidation. lias the defect -removing effect at the interface of Si -$SiO_2$. After dry or $NH_3$. oxidation. the annealmg 7.5% $NH_3/N_2$ ambient brings out gettering effect of OSF. The annealing in 7.5% $NH_3/N_2$ ambient for NI L oxidation method decreaSE,s $NH_3$ length of OSF about 20 % compared with dry oxidation method. Tlw feature of OSF is pit type, the gettering is directed to (011) plane for (111) plane. and OSFs are etched following to 110) directIon.

• Journal of the Korean Magnetics Society
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• v.23 no.1
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• pp.7-11
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• 2013

We investigate the perpendicular magnetic anisotropy in $TiO_2$/Co/Pd on GaAs(100), MgO(100), MgO(111), Si(100), and glass substrates. We find that the roughness of $TiO_2$ depends on the $O_2$ partial pressure in the magnetron sputtering process. The perpendicular magnetic anisotropies are found in all substrates with $TiO_2$ seed layer, and the perpendicular magnetic anisotropy of Co/Pd system is insensitive on the type of the substrate when the thickness of $TiO_2$ seed layer is thicker than 5 nm. However, MgO(111) substrate promotes $TiO_2$ rutile (111) structure, and it causes largest perpendicular magnetic anisotropy in $TiO_2$/Co/Pd(111) structures.

• Applied Microscopy
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• v.24 no.4
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• pp.132-144
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• 1994

The application of TEM in investigating the evolution of microstructure during solid phase crystallization of the amorphous Si, $Si_{1-x}Ge_x,\;and\;Si_{1-x}Ge_x/Si$ films deposited on $SiO_2$ substrate, in identifying the failure mechanism of the TiN barrier layer in the Cu-metallization scheme, and in comparing the microstructure of the as-deposited Cu-Cr and Cu-Ti alloy films are discussed. First, it is identified that the evolution of microstructure in Si and $Si_{1-x}Ge_x$ alloy films strongly depends on the concentration of Ge in the film. Second, the failure mechanism of the TiN diffusion barrier in the Cu-metallization is the migration of the Cu into the Si substrate, which results in the formation of a dislocation along the Si {111} plane and precipitates (presumably $Cu_{3}Si$) around the dislocation. Finally, the microstructure of the as-deposited Cu-Cr and Cu-Ti alloy films is also quite different in these two cases. From these several cases, we demonstrate that the information which we obtained using TEM is critical in understanding the behavior of materials.

• Journal of Magnetics
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• v.1 no.1
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• pp.4-8
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• 1996

Employing the LMTO band method, we have studied electronic and magnetic properties of Fe/Si/Fe trilayer in which the z-direction is chosen to be (111) direction of FeSi with B2 phase, We have also determined electronic structure of bulk FeSi, as a reference material. The ground state of FeSi is paramagnetic insulator with a band gap of 0.05 eV. Band structures of Fe/Si/Fe with varying the thickness of the spacer layer reveal that the spacer layer is metallic, and the states along the growth direction do not disperse much reflecting a two-dimensional nature. Magnetic moment of Fe atom in the interfacial layer of Fe/Si/Fe is reduced a lot as compared to the bulk value, suggesting a strong hybridization between Fe and Si states. The geometry of the Fermi surface indicates that the magnetic coupling period of ~8ML (monolayers) in Fe/Si/Fe is explained with a short Fermi wave vector of bcc Si.

• Proceedings of the KWS Conference
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• 1998.10a
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• pp.111-112
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• 1998

• Proceedings of the Korean Vacuum Society Conference
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• 1998.06a
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• pp.105-105
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• 1998