• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1459-1462
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• 2007

In general a thermoelectric cooler (TEC) consists of a series of P type and N type thermoelectric materials sandwiched between two wafers. When a DC current passes through these materials, three different effects take place; Peltier effect, Joule heating effect and heat transfer by conduction due to temperature difference between hot and cold plates. In this study we have developed a micro TEC using $Bi_2Te_3$ (N type) and $Bi_{0.5}Sb_{1.5}Te_3$ (P type) thin films. In order to improve that performance of a micro TEC, we made 10 um height TE legs using special PR only for lift-off. We measured COP (coefficient of performance) and temperature difference between hot and cold connectors with current.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.3
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• pp.201-207
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• 2011

Total heat recovery type ventilators that are connected to each room with ducts are mainly installed in Korea, but they raise concern over duct pollution. In this study, indoor environments made by thin line type ventilators installed in dwelling units of apartment houses are investigated by CFD. Results show the case that thin line type ventilators installed in each room-including kitchens-make the best indoor environment that maintains air velocity at under 0.25m/s, and evenly distributes the age of air in all areas.

• Journal of Information Display
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• v.6 no.4
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• pp.6-10
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• 2005

The dependence of hysteresis characteristics in low temperature poly-Si (LTPS) thin film transistors (TFTs) on the gate-source voltage (Vgs) or the drain-source voltage (Vds) bias is investigated and discussed. The hysteresis levels in both p-type and n-type LTPS TFTs are independent of Vds bias but increase as the sweep range of Vgs increases. It has been found that the hysteresis in both p-type and n-type LTPS TFTs originated from charge trapping and de-trapping in the channel region rather than at the source/drain edges.

• Korean Journal of Optics and Photonics
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• v.9 no.5
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• pp.282-290
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• 1998

The equivalent lens conversion technique is applied to design achromatic doublet and aplanatic doublet. A thin doublet which has zero axial thicknesses, are corrected for the third order aberrations at first, and the thin doublet is converted into thick lens system by using the equivalent lens conversion. Two types of cemented doublets, the Fraunhofer type and the Steinheil type, are designed by using a crown glass BaK-2 and a flint glass SF-2. In the thin doublet design, there are two achromatic solutions and a aplanatic solution for the both types.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.532-534
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• 2000

Si thin films on p-type (100) Si substrate have been fabricated by pulsed laser deposition technique using a Nd:YAG laser. The pressure of the environmental gas during deposition was varied from 1 to 3 Torr. After deposition, Si thin film has been annealed again at nitrogen ambient. Strong violet-indigo photoluminescence have been observed from Si thin film annealed in nitrogen ambient gas. As increasing environmental gas pressure, weak green and red emissions from annealed Si thin films also observed by photoluminescence.

• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.3
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• pp.182-186
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• 2005

In this work, thermal evaporation system was employed to deposit thin films of SiC on glass substrates in order to determine the parameters of them. Measurements included transmission, absorption, Seebak effect, resistivity and conductivity, absorption coefficient, type of energy band-gap, extinction coefficient as functions of photon energy and the effect of increasing film thickness on transmittance. Results explained that SiC thin film is an n-type semiconductor of indirect energy band-gap of ${\sim}3eV$, cut-off wavelength of 448nm, absorption coefficient of $3.4395{\times}10^{4}cm^{-1}$ and extinction coefficient of 0.154. The experimental measured values are in good agreement with the typical values of SiC thin films prepared by other advanced deposition techniques.

• Journal of the Korean Society of Costume
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• v.53 no.6
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• pp.145-159
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• 2003

The purpose of this study was to classify body type for ready-to-wear sizes. The subjects were 300 women ages of 18-24. they were measured direct anthropometry. The body types for sizing system were divided by Rohrer Index. KS drop value and ISO drop value. The results of this study were as follows. 1. By adapting the Rohrer Index. we classify 3 types from anthropometric measurements. The thin type covered 39.3%, the standard type 51.0% and the obesity type 18.7%. The characteristics of clusters were as follows. Thin type was characterized by tall. slender type and slim. The standard type was characterized by middle sized. The obesity type was characterized by short. fat type. and large bust. 2. By adapting the KS system drop value. we classify 3 types from anthropometric measurements. The H type(drop 0) covered 25.6%. the N type(drop 6) 65.2% and the A type(drop 12) 9.2%. Type H was slightly tall large bust. and curved from waist to hip. Type A was slightly thin. large hip and smaller bust than type N. Principal factor components were bust size. The height could be divided into three groups. The Petite(l50cm) covered 5.5%. the Regular(l60cm) 64.7% and the Tall(l70cm) 29.8%. Through the crosstab of height and body type. we extracted regular height by N type 46.2% the largest cell. The body type was the higher order of N type. H type and A type. The tall was the higher order of Regular. Tall and Petite. 3. By adapting the ISO system drop value. we classify 3 types from anthropometric measurements. The H type(drop 0) covered 15.0%. the M type(drop 6) 41.0% and the A type(drop 12) 44.0%. Type H was slightly short. slightly fat and large bust. Type A was slightly tall. slight thin than type M. The height could be divided into three groups. We adjust the height section after allow for height distribution. The Short(152cm) covered 12.8%. the Regular(160cm) 66.9% and the Long(168cm) 20.3%. Through the crosstab of height and body type, we extracted regular height by M type 29.3% the largest cell. The body type was the higher order of M type, A type and H type. The tall was the higher order of Regular, Long and short.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.226-226
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• 2012

The electronic and electrical properties of nickel oxide (NiO) thin films were investigated by reflection electron energy loss spectroscopy (REELS), x-ray photoelectron spectroscopy (XPS), and Hall Effect measurements. REELS spectra revealed that the band gap of the NiO thin film was increased from 3.50 eV to 4.02 eV after annealing the sample at $800^{\circ}C$. Our XPS spectra showed that the amount of Ni2O3 decreased after annealing. The Hall Effect results showed that the doping type of the sample changed from n type to p type after annealing. The resistivity decreased drastically from $4.6{\times}10^3$ to $3.5{\times}10^{-2}$ ${\Omega}{\cdot}cm$. The mobility of NiO thin films was changed form $3.29{\times}10^3$ to $3.09{\times}10^5cm^2/V{\cdot}s$. Our results showed that the annealing temperature plays a crucial role in increasing the carrier concentration and the mobility which leads to lowering resistivity of NiO thin films.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.223-226
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• 2004

MgO thin films were deposited bye-beam evaporation on $SiO_2$/Si wafers for the application of a protective layer in alternating current plasma display panels (AC-PDPs). Three different MgO sources, single crystal, melted polycrystal and sintered polycrystal, were used to find out the change of the properties of MgO protective layer depending on the source type. The properties of MgO thin films such as density, orientation and surface morphology were influenced by the source type. MgO thin films deposited with the melted polycrystal source had the highest density with the highest (100) preferred orientation, whereas the films deposited with the sintered polycrystal source had the lowest density with less preferred orientation. Such a result seems to be originated from the different mobility of adatoms on the surface of the deposited MgO thin films. Different microstructures of MgO thin films deposited even in the same deposition condition were observed depending on the MgO source type, resulting in different discharge characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.888-891
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• 2003

This paper describes on the fabrication and characteristics of micro ceramic thin-film type pressure sensors based on Ta-N strain-gauges for high-temperature applications. The Ta-N thin-film strain-gauges are deposited onto thermally oxidized Si diaphragms by RF sputtering in an argon-nitrogen atmosphere($N_2$ gas ratio: 8 %, annealing condition: $900^{\circ}C$, 1 hr.), Patterned on a wheatstone bridge configuration, and use as pressure sensing elements with a high stability and a high gauge factor. The sensitivity is $1.097{\sim}1.21mV/V.kgf/cm^2$ in the temperature range of $25{\sim}200^{\circ}C$ and the maximum non-linearity is 0.43 %FS. The fabricated pressure sensor presents a lower TCR, non-linearity than existing Si piezoresistive pressure sensors. The fabricated micro ceramic thin-film type pressure sensor is expected to be usefully applied as pressure and load sensors that is operable under high-temperature environments.