• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.1
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• pp.49-55
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• 2023

The deposition of indium zinc oxide (IZO) thin films was carried out on substrate at room temperature by RF magnetron sputtering. The effects of substrate temperature, RF power and deposition pressure were investigated with respect to physical and optical properties of films such as deposition rate, electrical properties, structure, and transmittance. As the RF power increases, the resistivity gradually decreases, and the transmittance slightly decreases. For the variation of deposition pressure, the resistivity greatly increases, and the transmittance is decreased with increasing deposition pressure. As a result, it was demonstrated that an IZO film with the resistivity of 3.89 × 10^-4 Ω∙cm, the hole mobility of 51.28 cm²/Vs, and the light transmittance of 86.89% in the visible spectrum at room temperature can be prepared without post-deposition annealing.

• Journal of the Korean institute of surface engineering
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• v.53 no.1
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• pp.9-14
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• 2020

CuS (copper sulfide) thin films having the same thickness of 100nm were deposited on the glass substrates using by radio frequency (RF) magnetron sputtering method. RF powers were applied as a process variable for the growth of CuS thin films. The structural and optical properties of CuS thin films deposited under different power conditions (40-100W) were studied. XRD analysis revealed that all CuS thin films had hexagonal crystal structure with the preferential growth of (110) planes. As the sputtering power increased, the relative intensity of the peak with respect to the (110) planes decreased. The peaks of the two bands (264cm^-1 and 474cm^-1) indicated in the Raman spectrum exactly matched the typical spectral values of the covellite (CuS). The size and shape of the grains constituting the surface of the CuS thin films deposited under the power condition ranging from 40W to 80W hardly changed. However, the spacing between crystal grains tended to increase in proportion to the increase in sputtering power. The maximum transmittance of CuS thin films grown at 40W to 80W ranged from 50 % to 51 % based on 580nm wavelength, and showed a relatively small decrease of 48% at 100W. The band gap energy of the CuS thin films decreased from 2.62eV (at 40W) to 2.56eV (at 100W) as the sputtering power increased.

• Journal of the Korean institute of surface engineering
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• v.34 no.5
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• pp.503-509
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• 2001

Thin films of hydrogenated amorphous silicon (a-Si : H) and hydrogenated amorphous silicon carbide (a-SiC:H) of different compositions were deposited on Si(100) wafer and glass by RF plasma-enhanced chemical vapor deposition (RF-PECVD). In the present work, we have investigated the effects of the RF power on the properties, such as optical band gap, transmittance and crystallinity. The Raman data show that the a-Si:H material consists of an amorphous and crystalline phase for the co-presence of two peaks centered at 480 and $520 cm^{-1}$ . The UV-VIS data suggested that the optical energy band gap ($E_{g}$ ) is not changed effectively with RF power and the obtained $E_{g}$(1.80eV) of the $\mu$c-Si:H thin film has almost the same value of a-Si:H thin film (1.75eV), indicating that the crystallity of hydrogenated amorphous silicon thin film can mainly not affected to their optical properties. However, the experimental results have shown that$ E_{g}$ of the a-SiC:H thin films changed little on the annealing temperature while $E_{g}$ increased with the RF power. The Raman spectrum of the a-SiC:H thin films annealed at high temperatures showed that graphitization of carbon clusters and microcrystalline silicon occurs.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.5
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• pp.560-566
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• 2004

In this paper, the electrical and emission properties of electrodeless fluorescent lamp were discussed using the inductively coupled plasma (ICP) with the variation of argon gas pressure and RF power. The RF output was applied to the antenna in the range of 5∼50 W at 13.56 MHz. The internal plasma voltage of the chamber and the probe current were measured while varying the supply voltage to the Langmuir probe in the range of －100V∼＋100V. When the pressure of argon gas was increased, electric current was decreased. There was a significant electric current increase from 10 to 30 W. Also, when the RF power was increased, electron density was increased. Also, the emission spectrum, Ar- I lins, luminance were investigated. At this time, the input parameter for ICP RF plasma, Ar gas pressure and RF power were applied in the range of 10∼60 mTorr, 10∼300 W, respectively. This implies that this method can be used to find an optimal RF power for efficient light illumination in an electrodeless fluorescent lamp.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.1
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• pp.1-4
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• 2001

We have fabricated and evaluated a new Si pin photodetector for APF optical link. The fabricated device has the $p^{+}$-guard ring around the metal-semiconductor contact and the web patterned $p^{+}$-shallow diffused region in the light absorbing area. From the measurements of electo-optical characteristics under the bias of -5 V, the junction capacitance of 4 pF and the dark current of 180 pA were obtained. The optical signal current of 1.22 $\mu$A and the responsivity of 0.55 A/W were obtained when the 2.2 $\mu$W optical power with peak wavelength of 670 nm was incident on the device. The fabricated device showed the maximum spectral response in a spectrum of 650-700 nm. It is expected that the fabricated device can be very useful for detecting the optical signal in the application of red light optics.

• Korean Journal of Optics and Photonics
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• v.5 no.2
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• pp.266-271
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• 1994

The output power and the energy of Rh-6G dye laser were enhanced by the mixture of Rh-560 dye whose fluorescence spectrum was coincident with the absorption spectrum of Rh-6G. The argon filled coaxial flashlamp used for pulsed pumping and argon laser for CW pumping. The concentration of Rh-6G dye was optimized in each pumping method before Rh-560 dye was mixed in Rh-6G dye solution. In the coaxial flash lamp pumped Rh-6G laser the output energy was increased about 30% when Rh-560 was mixed at 1% of Rh-6G concentration. In the case of argon laser pumping with multiline, the output power was increased 18% at the concentration of 2.5%. In the single line laser pumping, the output power was enhanced more efficiently. The power enhancements were 72% and 88% when the pumping wavelengths were 488 nm and 514.5 nm respectively. ively.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.35-44
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• 2006

Reflective semiconductor optical amplifiers(R-SOAs) were designed with high gain, wide optical bandwidth, high thermal reliability and wide modulation bandwidth in TO-can package for the transmitter of wavelength division multiplexed-passive optical network(WDM-PON) application. Double trench structure and current block layer were introduced in designing the active layer of R-SOA to enable high speed modulation. The injection power requirement and the viable temperature range of WDM-PON system are experimentally analysed in based on Amplified Spontaneous Emission(ASE)-injected R-SOAs. The effect of the different injection spectrum in the gain-saturated R-SOA was experimentally characterized based on the measurements of excessive intensity noise, Q factor, and BER. The proposed spectral pre-composition method reduces the bandwidth of injection source below the AWG bandwidth and thereby avoids spectrum distortion impeding the intensity noise reduction originated from the amplitude squeezing.

• Korean Journal of Optics and Photonics
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• v.10 no.5
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• pp.396-400
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• 1999

In the fiber-optic gyroscope employing a high-power erbium-doped fiber source, the source excess noise was subtracted from the gyro output through a single processing to improve the gyroscope sensitivity. As the result, we obtained the reduction of noise by 13.5 dB (electrical) which was measured from the noise floor spectrum when the gyro was modulated with the depth of 1.8 rad. In addition, the random walk coefficient of the gyro output was reduced by a factor of 4~5.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.263-268
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• 2008

Building Integrated PV(BIPV) is one of the best fascinating PV application technologies. To apply PV module in building, various factors should be reflected such as installation position, shading, temperature, and so on. Especially a temperature should be considered, for it affects both electrical efficiency of a PV module and heating/cooling load in a building. This study investigates a semitransparent PV module that is designed as finished material for windows. Therefore it needs to considerate about the optical characteristics of the transparent module. It reports the effect of thermal and optical characteristics of the PV module on generation performance. The study was performed by measuring sun spectrum and luminance through the PV modules and by monitoring the temperature and experiment. The results showed that 1 degree temperature rise reduced about 0.48% of output power.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.31-35
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• 2011

Photovoltaic modules are well known to be one of the most eco generation of electricity. But usually study solar cell. Otherwise, PV modules are also important in power generation. We have to check other subsidiary materials. In this work benefit of using optically superior encapsulation materials(EVA) in generation temperature is demonstrated. Optical characterization of three EVA products demonstrates reduced transmission in the visible ray region of the solar spectrum. It will have a decisive effect to the module efficiency. Test is shown reduction of reflectance and transmittance. Reflections is dependent on the low iron glass. It can be seen between a specific wave length(240~350mm) about 1%. Transmittance in the entire ray region of light is markedly reduced to depending on the temperature rise. The graph is shown optical properties on EVA. Transmission was reduced. about 1%.