• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.55-56
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• 2006

We investigated the diffraction grating efficiency by the DPSS laser beam wavelength to improve the diffraction efficiency on AsGeSeS & Ag/ AsGeSeS thin film. Diffraction efficiency was obtained from DPSS(532nm)(P:P)polarized laser beam on AsGeSeS, Ag/ AsGeSeS and AsGeSeS/Ag/AsGeSeS thin films. As a result, for the laser beam intensity, 0.24 mW, single AsGeSeS thin film shows the highest value of 0.161% diffraction efficiency at 300 s and for 2.4 mW, it was recorded with the fastest speed of 50 s, which the diffraction grating forming speed is faster than that of 0.24 mW beam. Ag/ AsGeSeS and AsGeSeS/ Ag/ AsGeSeS multi-layered thin film also show the faster grating forming speed at 2.4 mW and higher value of diffraction efficiency at 0.24 mW.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.3
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• pp.240-244
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• 2007

We investigated the diffraction grating efficiency by the Diode Pumped Solid State(DPSS 532 nm) laser beam wavelength to improve the diffraction efficiency on $As_{40}Ge_{10}Se_{15}S_{35},\;Ag/As_{40}Ge_{10}Se_{15}S_{35}$ and $As_{40}Ge_{10}Se_{15}S_{35}/Ag/As_{40}Ge_{10}Se_{15}S_{35}$ thin film. Diffraction efficiency was obtained from DPSS laser, used (P:P)polarized laser beam on each thin films. As a result, for the laser beam intensity in $0.24mW/cm^2$, single $As_{40}Ge_{10}Se_{15}S_{35}$ thin film shows the highest value of 0.161% diffraction efficiency at 300 s and for laser beam intensity in $2.4mW/cm^2$, it was recorded with the fastest speed of 50 s(0.013%), which the diffraction grating forming speed is faster than that of $0.24mW/cm^2$ beam. $Ag/As_{40}Ge_{10}Se_{15}S_{35}$ double layer and $As_{40}Ge_{10}Se_{15}S_{35}/Ag/As_{40}Ge_{10}Se_{15}S_{35}$ multi-layered thin film also show the faster grating forming speed at $2.4mW/cm^2$ and higher value of diffraction efficiency at $0.24mW/cm^2$.

• Journal of the Korean Vacuum Society
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• v.22 no.2
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• pp.86-91
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• 2013

The optical properties of InAs quantum dots (QDs) grown on GaAs substrates grown by molecular beam epitaxy have been studied using photoluminescence (PL) and time-resolved PL measurements. InAs QDs were grown using an arsenic interruption growth (AIG) technique, in which the As flux was periodically interrupted by a closed As shutter during InAs QDs growth. In this study, the shutter of As source was periodically opened and closed for 1 (S1), 2 (S2), or 3 s (S3). For comparison, an InAs QD sample (S0) without As interruption was grown in a pure GaAs matrix for 20 s. The PL intensity of InAs QD samples grown by AIG technique is stronger than that of the reference sample (S0). While the PL peaks of S1 and S2 are redshifted compared to that of S0, the PL peak of S3 is blueshifted from that of S0. The increase of the PL intensity for the InAs QDs grown by AIG technique can be explained by the reduced InAs clusters, the increased QD density, the improved QD uniformity, and the improved aspect ratio (height/length). The redshift (blueshift) of the PL peak for S1 (S3) compared with that for S0 is attributed to the increase (decrease) in the QD average length compared to the average length of S0. The PL intensity, PL peak position, and PL decay time have been investigated as functions of temperature and emission wavelength. S2 shows no InAs clusters, the increased InAs QD density, the improved QD uniformity, and the improved QD aspect ratio. S2 also shows the strongest PL intensity and the longest PL decay time. These results indicate that the size (shape), density, and uniformity of InAs QDs can be controlled by using AIG technique. Therefore the emission wavelength and luminescence properties of InAs/GaAs QDs can also be controlled.

• Journal of Technology Innovation
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• v.5 no.1
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• pp.113-149
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• 1997

This paper, searching for the origin of the science and technology policy, is one of the research series on the original form of current S&T policy such as origin, evolution and changing patterns. Without understanding the origin, it is very difficult to understand the evolution and the current change of the policy. To answer this question, 2 kinds of conditions are set: 4 concepts for the origin of a policy and also 4 conditions for the S&T policy itself. As the origin of a policy, 4 concepts are set such as independence, continuance, diffusion and modern state as a policy body. Also as conditions for S&T policy, there may be 4 conditions such as policy targets, policy functions, administration body and the usage of the name of the policy. S&T can be distinguished as science, technology and S&T along it's development path. There, hence, are 2 origins of science and technology policy. French policy for modern science at the late 18th century and the establishment of the Agency of Science and Technology Policy of Japan in 1956 can be pointed out as the origin of the policy. The former can be called as the origin for natural science, and the latter as the origin for S&T. This study implies that new paradigm of S&T policy is a reflection for both the needs of new S&T and social needs. When there were big problems in a society and when there appeared new S&T, they exploited new S&T vigorously. This has been remained as a rememberable monuments in the history of the S&T policy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.823-827
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• 2001

The AgInS$_2$epilayers with chalcopyrite structure grown by using a hot-wall epitaxy (HWE) method have been confirmed to be a high quality crystal. From the optical absorption measurement, the temperature dependence of the energy band gap on the AgInS$_2$/GaAs was derived as the Varshni's relation of Eg(T)=2.1365 eV-(9.89${\times}$10$\^$-3/ eV)T$^2$/(2930+T). After the as-grown AgInS$_2$/GaAs was annealed in Ag-,S-, and In-atmosphere, the origin of point defects of the AgInS$_2$/GaAs has been investigated by using the photoluminescence (PL) at 10 K. The native defects of V$\_$Ag/, V$\_$s/, Ag$\_$int/, and S$\_$int/ obtained from PL measurement were classified to donors or acceptors type. And, we concluded that the heat-treatment in the S-atmosphere converted the AgInS$_2$/GaAs to optical p-type. Also, we confirmed that the In in the AgInS$_2$/GaAs did net from the native defects because the In in AgInS$_2$did exist as the form of stable bonds.

• KSBB Journal
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• v.10 no.1
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• pp.71-77
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• 1995

Characteristics of S-acid and its derivatives, as biosurfactants, were investigated. Sodium salt of S-acid(S-lNa) effectively decreased the surface tension to near 30 dyne/cm and showed superior dispersing ability than commercial surfactants such as SDS and Tween 80. The emulsion made by S-lNa could be maintained even with increased concentration of calcium ion. Also the penetratlng ability of S-lNa was observed as effective as that of LAS. All derivatives of S-acid were degraded by microorganisms much faster than conventional surfactants. Among the derivatives, S-3Na prevented rust formation as effectively as commercial anti-rust agents did.

• Transactions on Electrical and Electronic Materials
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• v.5 no.2
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• pp.50-54
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• 2004

The AgInS$_2$epilayers with chalcopyrite structure grown by using a hot-wall epitaxy (HWE) method have been confirmed to be a high quality crystal. From the optical absorption measurement, the temperature dependence of the energy band gap on the AgInS$_2$/GaAs was derived as the Varshni's relation of E$\_$g/(T) = 2.1365 eV - (9.89${\times}$10$\^$－3/ eV/K) T$^2$/(2930＋T eV). After the as-grown AgInS$_2$/GaAs was annealed in Ag－, S－. and In-atmosphere, the origin of point defects of the AgInS$_2$/GaAs has been investigated by using the photoluminescence (PL) at 10 K. The native defects of $V_{Ag}$, $V_s$, $Ag_{int}$, and $S_{int}$ obtained from PL measurement were classified to donors or accepters type. And, we concluded that the heat-treatment in the S- atmosphere converted the AgInS$_2$/GaAs to optical p-type. Also, we confirmed that the In in the AgInS$_2$/GaAs did not form the native defects because the In in AgInS$_2$did exist as the form of stable bonds.

• Journal of Families and Better Life
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• v.16 no.1
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• pp.81-94
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• 1998

The purpose of this study is to examine men's role conflicts of dual-earner family based on man's role type. Man's role type is composed of man's sex role attitude and family-role performance and categorized in four types such as traditionalism type neo-traditionalism type equalitarianism type and inconsistancy type. The test analysis can be summarized as follows; First test analysis can be summarized as follows; role performance and man's role conflict as working hours is long wife's role requirement is high family-role conflict as working hours is long wife's role requirement is high family-role is not commit man's role conflict directly affected. In addition indirect affect through family-role performance shows that man's role conflict level is low as level of income is high level of income difference between man and wife is low child is younger and intent to modern sex-role attitude. Second looking into the difference role conflict to man's role type it shows that equalita ianism type's role conflict is low and man's role conflict in traditionalism and neo-traditonalism types is high.

• Proceedings of the Optical Society of Korea Conference
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• 1991.06a
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• pp.98-101
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• 1991

The As2S3 thin film has a characteristics of optical modulation in both amplitude and phase. Since the As2S3 thin film can be used as a real-time reconfigurable optical filter, the fSDF filter can be optically fabricated on it. According to the modulation characteristics of the As2S3, the optimal fSDF filter recorded on this thin plate has the form of continuous amplitude and binary phase. Computer simulation and optical experiments on the optical pattern classification show that the As2S3 is suitable for the optical fSDF filter.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.4
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• pp.196-201
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• 2002

The $AgInS_{2}$ epilayers with a chalcopyrite structure grown using a hot-wall epitaxy method have been confirmed to be a high quality crystal. From the optical absorption measurements, a temperature dependence of the energy band gap on $AgInS_{2}/GaAs$ was found to be $Eg(T)=2.1365eV-(9.89{\times}10^{-3}eV)T^{2}/(2930+T)$. After the as-grown $AgInS_{2}/GaAs$ was annealed in Ag-, S-, and In-atmospheres, the origin of point defects of $AgInS_{2}/GaAs$ has been investigated by using photoluminescence measurements at 10 K. The native defects of $V_{Ag},\;V_{S},\;Ag_{int}$ and $S_{int}$ obtained from photoluminescence measurements were classified as donors or accepters. It was concluded that the heat-treatment in the S-atmosphere converted $AgInS_{2}/GaAs$ to an optical p-type. Also, it was confirmed that In in $AgInS_{2}/GaAs$ did not form the native defects because In in $AgInS_{2}$ did exist in the stable form.