• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.73-76
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• 2001

We deposited epitaxial $Ba_{0.6}$S $r_{0.4}$Ti $O_3$(BST) films having thickness of 400 nm on MgO(001) substrates, where a 10 nm thick $Ba_{1-x}$S $r_{x}$Ti $O_3$(x=0.1-0.7) interlayer was inserted between BST and MgO to manipulate the stress of the BST films. Since the main difference of those epitaxial BST films was the lattice constant of the interlayers, we were very successful in controlling the stress of the BST films. BST films under small tensile stress showed larger dielectric constant than that without stress as well as those under compressive stress. Stress relaxation was investigated using epitaxial BST films with various thicknesses grown on different interlayers. For BST films grown on $Ba_{0.7}$S $r_{0.3}$Ti $O_3$ interlayers, the critical thickness was about 600 nm. On the other hand, the critical thickness of single-layer BST film was less than 100 nm.00 nm.m.m.m.

• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.4
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• pp.288-294
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• 2002

This paper presents the design, fabrication and characterization of a 32 by 32 electroplated micromirror array on a glass, a low cost substrate. Approaches taken in this work for the fabrication of micromachined mirror arrays include a line addressing scheme, a seamless array design for high fill factor, planarization techniques of polymeric interlayers, a high yield methodology for the removal of sacrificial polymeric interlayers, and low temperature and chemically safe fabrication techniques. The micromirror is fabricated by aluminum and the size of a single micromirror is 200 $\mu\textrm{m}{\;}{\times}200{\;}\mu\textrm{m}$. Static deflection test of the micro-mirror has been carried out and pull-in voltage of 44V and releasing voltage of 30V was found.

• Journal of the Korean Ceramic Society
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• v.33 no.3
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• pp.251-258
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• 1996

The reactions between an active metal brazing alloy and interlayers together with the effects of interlayer type on the interfacial microstructure change were investiaged for silicon nitride/stainless steel joint. The bending strengths were measured for joints with Mo, Cu, Ni interlayer type of different thicknesses. It was found that the interlayer with a low yield strength value is effective to improve the bending strength of the Si3N4/stainless steel joint. The maximum joint strength obtained at room temperature for a laminated Cu/Mo interlayer was about 460 MPa. The combined use of Mo and thin Cu layer was found to be effective in enhancing the bending strength for the Si3N4/S.S.316 joint.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.114.2-114.2
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• 2014

The orientation of the constituent molecules in organic thin film devices can affect significantly their performance due to the highly anisotropic nature of ${\pi}$-conjugated molecules. We report here an angle dependent x-ray absorption study of the control of such molecular orientation using well-ordered interlayers for the case of a bilayer heterojunction of chloroaluminum phthalocyanine (ClAlPc) and C60. Furthermore, the orientation-dependent energy level alignment of the same bilayer heterojunction has been measured in detail using synchrotron radiation-excited photoelectron spectroscopy. Regardless of the orientation of the organic interlayer, we find that the subsequent ClAlPc tilt angle improves the ${\pi}-{\pi}$ interaction at the interface, thus leading to an improved short-circuit current in photovoltaic devices based on ClAlPc/C60. The use of the interlayers does not change the effective band gap at the ClAlPc/C60 heterointerface, resulting in no change in open-circuit voltage.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.9
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• pp.672-675
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• 1999

Si-to-Si electrostatic bonding was carried out by employing LSG interlayer instead of conventional Corning #7740 interlayer in order to improve bonding properties. The surface roughness and dielectric breakdown field of the LSG interlayers deposited on Si substrates were investigated. Also, the bonding interface, bonding strength and bonding mechanism were discussed for the electrostatically-bonded Si-Si wafer pairs having LSG interlayers.

• Korean Journal of Materials Research
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• v.13 no.5
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• pp.279-284
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• 2003

The $CoSi_2$ process is widely employed in a salicide as well as an ohmic layer process. In this experiment, we investigated the characteristics of $CoSi_2$ films by combinations of I-type (TiN 100$\AA$/Co 150$\AA$), II-type(TiN 100$\AA$/Co 150$\AA$/Ti 50$\AA$), III-type(Ti 100$\AA$/Co 150$\AA$/Ti 50$\AA$), and IV-type(Ti 100$\AA$/Co 150$\AA$/Ti 100$\AA$). Sheet resistances of $CoSi_2$ show the lowest resistance with 2.9 $\Omega$/sq. in a TiN/Co condition and much higher resistances in conditions simultaneously applying Ti capping layers and Ti interlayers. Though we couldn't observe a $CoSi_2$roughness dependence on the film stacks from RMS values, Ti capping layers turned into 78∼94$\AA$ thick TiN layers of (200) preferred orientation at $N_2$ambient. In addition, Ti interlayers helped to form the epitaxial $CoSi_2$with (200) preferred orientation and ternary compounds of Co-Ti-Si. We propose that film structures of II-type and III-type may be appropriate in the salicide process and the ohmic layer process from the viewpoint of Co diffusion kinetics and the CoSi$_2$epitaxy.

• Journal of the Korean Electrochemical Society
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• v.2 no.4
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• pp.221-226
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• 1999

Two needle cokes (NC-A and NC-B) that differ in both the texture and impurity content to each other were graphitized at $2000-3000{\circ}C$, and the average particle size, size distribution and surface area were compared after milling. Their anodic properties in Li secondary batteries were also analyzed. Two materials showed a higher degree of graphitization with an increase in the preparation temperature, however, the NC-B series was less graphitized than NC-A due to the presence of impurities and less ordered mosaic texture. The mein particle size of the milled powder was proportional to the degree of graphitization, but the surface area showed the opposite trend. The highly graphitized materials yielded powders of lower uniformity in the size distribution. The discharge capacity of the resulting carbons steadily decreased in the temperature range of 1000 to $2000^{\circ}C$ due to the depletion of carbonaceous interlayers that contain crystal defects. A later increase in the discharge capacity was observed at $>2000^{\circ}C$, which arises from the formation of graphitic interlayers. The milling process gave rise to a sloping discharge curve at >1.0 V, but this was converted to a plateau at <0.25V after a repeated cycling or additional heat-treatment at $1000^{\circ}C$. The discharge at >1.0V likely comes from the disordered surface structure formed during the milling process. The evolution of a plateau at <0.25 V suggests that this disordered structure transforms to a more ordered graphitic one upon a cell cycling or heat-treatment.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.135.2-135.2
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• 2005

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.531-533
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• 1996

• Proceedings of the Korean Magnestics Society Conference
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• 2003.06a
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• pp.36-37
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• 2003