• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.224-227
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• 2006

We have chained 459nm blue laser radiation generated by intracavity sum frequency generation( SFG ) due to the mixing of the 1064 nm laser output of a Nd:YVO4 pumped by diode and the 809nm radiation from higg-power semiconductor laser(500mW). The maximum blue output power of 0.95 mW was obtained using 400 mW input power of semiconductor laser at the type II phase matching condition (${\psi}=90^{\circ}\;{\theta}=90^{\circ}$). The threshold input power of blue laser generation was 120 mW.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.2
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• pp.17-22
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• 2008

To develop an imaging optical system for the 545 nm fluorescent plate of X-ray. Methods: We designed and manufactured a new imaging optical system for the 545 nm fluorescent plate of X-ray by Sigma 2000 program after deciding the design comparison standards referred to Canon CX2-70 model. Results: The characteristics of the new imaging optical system for the 545 nm fluorescent plate of X-ray have the magnification of -0.225x, the image field size of $90mm{\times}90mm$, and the 0.033 mm resolution line width at the 30% MTF value criterion. These mean that the new model has a capability of deciphering for the more large screen and the resolution of deciphering is superior to that of Canon CX2-70 model. Also the image side NA (-0.196) of the new model is about $\sqrt{2}$ times than that (-0.139) of CX2-70 and the object side NA (0.044) of the new model is about 2 times than that (0.022) of CX2-70. These mean that the sensitivity of the film in the new design model is able to be increased to about 4 times and there is the possibility of reducing the bombed time of X-ray to 1/4 times. Conclusions: We could design and manufacture the imaging optical system for the 545 nm fluorescent plate of X-ray having the possibility of reducing the bombed time of X-ray to 1/4 times in comparision to Canon CX2-70 model, the characteristics of which have the image field size of $90mm{\times}90mm$ and the MTF of 30% or more at 15 lines/mm criterion.

• Korean Journal of Optics and Photonics
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• v.8 no.3
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• pp.183-188
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• 1997

Cut-off filters would reject all the radiation below and transmit all that above a certain wavelength or vice versa. In this paper, we study design and farbrication of dichroic mirror and broadband high reflective mirror for color separation of white laser beam source to R.G.B color beam source. In laser display system, color separation is very important. We fabricated below specific component for finite color separation of the Kr-Ar laser source. At 45$^{\circ}$ incidence s-polarized light , it is required that - H/R in blue region R>99%, H/T in green and red region T>90% - H/R in green and red region R>99%, H/T in blue region T>90% - H/R in green region R>99%, H/T in red region T>90% We composed the optical system and realize the full color image.

• Journal of the Korean Magnetics Society
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• v.18 no.5
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• pp.180-184
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• 2008

The relation of ferromagnet anisotropic magnetization and the antiferromagnet atomic spin configuration has been investigated for variously angles of unidirectional deposition magnetic field of FeMn layer in Corning glas/Ta(5 nm)/NiFe(7 nm)/FeMn(25 nm)/ Ta(5 nm) multilayer prepared by ion beam deposition. Three unidirectional deposition angles of FeMn layer are $0^{\circ},\;45^{\circ}$, and $90^{\circ}$, respectively. The exchange bias field ($H_{ex}$) obtained from the measuring easy axis MR loop was decreased to 40 Oe in deposition angle of $45^{\circ}$, and to 0 Oe in the angle of $90^{\circ}$. One other side hand, $H_{ex}$ obtained from the measuring hard axis MR loop was increased to 35 Oe in deposition angle of $45^{\circ}$, and to 79 Oe in the angle of $90^{\circ}$. Although the difference of uniderectional axis between ferromagnet NiFe and antiferromagnet FeMn was 90o, the strong antiferromagnetic dipole moment of FeMn caused to rotate the weak ferromagnetic dipole moment of NiFe in the interface. This result implies that one of origins for exchange coupling mechanism depends on the effect of magnetic field angle during deposition of antiferromgnet FeMn layer.

• Korean Journal of Optics and Photonics
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• v.8 no.6
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• pp.450-455
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• 1997

A pulsed Ti:sapphire laser with a Z-folded cavity, which was pumped by a freqeuncy-doubled Nd:YAG laser, was developed. It shows 120 nm wavelength tuning range from 740 nm to 860 nm with 90 nm FWHM under a pumping energy of 3 mJ with 18% output coupler. Using a birefringent filter, the effective efficiency was improved about 10 times compare to without a birefringent filter. The output energy obtained was $\365mu$Jwith 4 nm FWHM. And the wavelength tuning range was broadened to about 160 nm within an output energy fluctuation of $\pm$10%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.424-427
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• 2001

Combining ability study was carried out on the components of synchronization in maturity and determinate growth habit in mungbean, using 6$\times$6 diallel cross. Both additive and non-additive gene effects were found conditioning the inheritance of days to first flower, days between first pod and 90% pod maturity (DDd1), plant height from first pod stage to 90% pod maturity (DDhl, DDh2, and DDh3). Only non-additive gene action was important in degree of determination from first pod stage to 90% pod maturity (DDd2). While only additive action was important in plant height at first flower. The predominant additive gene action was observed in all traits but non-additive was significant in only DDd$_2$. For synchronization in maturity, determinate growth habit, and their components, the best combiners were NM92, VCl560D, and NM89, whereas the best indeterminate combinations were NM92 $\times$ NM89, NM92 $\times$ VCl560D, and NM92 $\times$ ML-5.

• Korean Journal of Optics and Photonics
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• v.7 no.4
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• pp.390-396
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• 1996

A pulsed Ti : sapphire laser with a Z-folded cavity, which was pumped by a frequency-doubled Nd : YAG laser, was developed. A laser output energy of 822 $\mu$J with a pulsewidth of 5 ns and an output efficiency of 27.4% was obtained at a center wavelength of 790 nm using an output coupler of 18% reflectance. The slope efficiency was 35%. The output beam diameter was 0.9 mm, and the divergence angle was 1.8 mrad. The spectrum tunability was about 120 nm from 740 nm to 860 nm with a FWHM of 90 nm at an 18% output coupler and a pumping energy of 3 mJ.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.2
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• pp.76-82
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• 2003

The robust stack storage node and sufficient cell capacitance for high performance is indispensable for 90 nm DRAM capacitor. For the first time, we successfully demonstrated MIS capacitor process integration for 90 nm DRAM technology. Novel cell layout and integration technology of 90 nm DRAM capacitor is proposed and developed, and it can be extended to the next generation DRAM. Diamond-shaped OCS with 1.8 um stack height is newly developed for large capacitor area with better stability. Furthermore, the novel $Al_2O_3/HfO_2$ dielectric material with equivalent oxide thickness (EOT) of 25 ${\AA}$ is adopted for obtaining sufficient cell capacitance. The reliable cell capacitance and leakage current of MIS capacitor is obtained with ~26 fF/cell and < 1 fA/ceil by $Al_2O_3/HfO_2$ dielectric material, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.777-779
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• 2003

In this paper, we have investigated Characteristics of C-V for Double gate MOSFET with main gate and side gate. DG MOSFET has the main gate length of 50nm and the side gate length of 70nm. We have investigated characteristics of C-V and main gate voltage is changed from -5V to ＋5V. Also we have investigated characteristics of C-V for DG MOSFET when the side gate length is changed from 40nm to 90nm. As the side gate length is reduced, the transconductance is increased and the capacitance is reduced. When the side gate voltage is 3V, we know that C-V curves are bending at near the main gate voltage of 1.8V. We have simulated using ISE-TCAD tool for characteristics analysis of device.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.3
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• pp.261-264
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• 2005

The 90 nm gate pattern technology have been virtualized by employing the hard mask and the planarization of fate poly silicon. We fabricated 70nm poly-Si on $200 nm-SiO_2/p-Si(100)$ substrates using low pressure chemical vapor deposition (LPCVD) to investigate roughness evolution by varying rapid annealing temperatures. The samples were annealed at the temperatures of $700^{\circ}C\~1100^{\circ}C$ for 40 seconds with a rapid thermal annealer. The surface image and the surface roughness were measured by a field emission scanning electron microscopy (FESEM) and an atomic force microscopy (AFM), respectively. The poly silicon surface became more rough as temperature increased due to surface agglomeration. The optimum conditions of poly silicon planarization were achieved by annealed at $700^{\circ}C$ for 40 seconds.