• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.12
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• pp.142-148
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• 1995

Sb ${\delta}$-doped Si layers were grown by Si MBE (Molecular Beam Epitaxy) system using substrate temperature modulation technique. The Si substrate temperatures were modulated between 350$^{\circ}C$ and 600$^{\circ}C$. The doping profile was as narrow as 41$\AA$ and the doping concentration of up to 3.5${\times}10^{20}cm^{3}$ was obtained. The film quality was as good as bulk material as verified by RHEED (Reflected High Energy Electron Diffraction), SRP (Spreading Resistance Profiling) and Hall measurement. Since the film quality is not degraded after the growth a Sb ${\delta}$-doped Si layer, the ${\delta}$-doped layers can be repeated as many times as we want. The doping technique is useful for many Si devices including small scale devices and those which utilize quantum mechanical effects.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.675-677
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• 2012

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.52.4-52
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• 1998

• Journal of the Korean Applied Science and Technology
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• v.7 no.1
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• pp.1-11
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• 1990

• Journal of the Korean Chemical Society
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• v.59 no.1
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• pp.18-21
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• 2015

We use a scanning tunneling microscope based break-junction technique to measure the conductance of a 4,4'-dimethoxybiphenyl molecular junction formed with Ag and Au electrodes. We observe the formation of a clear molecular junction with Ag electrodes that result from stable Ag-oxygen bonding structures. However we have no molecular bonding formation when using Au electrodes, resulting in a tunneling current between the top and bottom metal electrodes. We also see a clear peak in the conductance histogram of the Ag-oxygen molecular junctions, but no significant molecular features are seen with Au electrodes. Our work should open a new path to the conductance measurements of single-molecule junctions with oxygen linkers.

• Journal of Magnetics
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• v.3 no.3
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• pp.89-91
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• 1998

The magnetisation behaviour of polycrystalline permalloy/copper multilayers with mixed antiferromagnetic/ferromagnetic coupling was investigated as function of temperature. The results are discussed in a framework of a realistic model of anitferromagnetically coupled layers connected by ferromagnetic pinholes. A microstructure of pinholes (their density and dimensions) was varied either by a proper annealing treatment or by choosing samples with various Cu spacer thicknesses. It was demonstrated that the temperature changes of the net magnetic moment measured in a magnetic field smaller than the saturation field was strongly affected by the composition of the pinholes, their density, cross-sectional area and their lengths.

• Electrical & Electronic Materials
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• v.16 no.6
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• pp.21-28
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• 2003

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.9
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• pp.38-48
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• 2000

This paper presents the photonic bandgap structure that has a defect mode within a broad stopband. In order to create a broad stopband, we eliminated one of periodic stopbands of PBG structure by using a quarter-wavelength transformer and cascaded another PBG structure having a center frequency corresponding to the eliminated stopband. We have demonstrated that it is a simple and effective method that can solve an overlapping problem of periodic stopband in two cascaded PBG structures.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.96-101
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• 2013

In this paper we analyzed the effects of polystyrene(PS) blended in TIPS-pentacene on the performance of OTFTs. With the various molecular weight and the content of PS the performance of TIPS-pentacene OTFTs was examined and the proper molecular weight and the content were extracted for the best results. With the molecular weight of 9,580 and 0.3 wt% of PS OTFTs produced the mobility of $1.0{\pm}0.19cm^2/V{\cdot}sec$, the subthreshold slope $0.22{\pm}0.05$ V/dec, the threshold voltage $-1.19{\pm}1.21$ V, the current on/of ratio $7.12{\pm}2.09{\times}10^6$. Additionally the suitable substrate temperature for ink jet printing of the blended TIPS-pentacene OTFTs was also extracted and it was $46^{\circ}C$.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.3
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• pp.53-59
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• 2011

Charge transfer through DNA oligonucleotides has been investigated for potential applications of DNA into molecular electrooptic switching devices. Electrons were injected using gold electrode probes where DNA oligomers were adsorbed that are separated in medium. The results show that increased adsorption of DNA reduces the ionization current due to the combined effect of charge transfer through DNA and surface-limited charge transport. The probe-based charge injection was extended to examine the capability of extinguishing fluorescence of Cy3 dye molecules attached to DNA. It is expected that the results may be employed to implementing a novel electrooptic switching device based on DNA molecules.