• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.141-144
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• 2004

A QVGA active-matrix backplane is produced on a 25${\mu}m$ thin plastic substrate. A 4-mask photolithographic process is used. The insulator layer and the semiconductor layer are organic material processed from solution. This backplane is combined with the electrophoretic display effect supplied by SiPix and E ink, resulting in an electronic paper display with a thickness of only 100${\mu}m$. This is world's thinnest active-matrix display ever made.

• Journal of Information Display
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• v.10 no.4
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• pp.180-183
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• 2009

A stamping-assisted rubbing technique for generating bidirectional alignment in the fabrication of wide-viewing twistednematic (TN) liquid crystal displays (LCDs) was developed. A patterned layer of a fluorinated acrylate polymer was transferred onto the first rubbed alignment layer prepared on a substrate by stamping. The fluorinated acrylate polymer provides a protective layer that covers the first alignment layer during the second rubbing process to facilitate the bidirectional alignment of the LC molecules. The LC cell in the twisted geometry with two bidirectional-alignment layers showed stable electro-optic properties and wide-viewing characteristics. The stamping-assisted rubbing technique serves as a mask-free alignment method of producing multidomains for wide-viewing LCDs.

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.39.2-39
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.189-189
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• 2002

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.4
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• pp.164-168
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• 2011

Etch selectivities of mask materials to ZnO and $SnO_2$ films were studied in $BCl_3$/Ar and $CF_4$/Ar inductively coupled plasmas for fabrication of nanostructure-based gas sensing layer with high aspect ratios. In $25BCl_3$/10Ar ICP discharges, selectivities of 5.1~6.1 were obtained for ZnO over Ni while no practical selectivity was obtained for ZnO over Al. High selectivities of 7 ~ 17 for ZnO over Ni were produced in $25CF_4$/10Ar mixtures. $SnO_2$ showed much higher etch rates than Ni and a maximum selectivity of 67 was observed for $SnO_2$ over Ni.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.3
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• pp.65-71
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• 1999

The effects of mask materials and etching solutions on the dimensional accuracy of V-groove were studied for the alignment between optoelectronic devices and optical fibers in optical packaging. PECVD nitride, LPCVD nitride, or thermal oxide($SiO_2$) was used as a mask material. The anisotropic etching solution was KOH(40wt%) or the mixture of KOH and IPA. LPCVB nitride has the best etching selectivity and thermal oxide was etched most rapidly in KOH(40wt%) at $85^{\circ}C$ among the mask materials studied here. The V-groove size enlarged than the designed value. This phenomenon was due to the undercutting benearth the mask layer from the etching toward Si (111) plane. The etch rate of (111) plane wart 0.034 - 0.037 $\mu\textrm{m}$/min in KOH(40wt%). This rate was almost same regardless of mask materials. When IPA added to KOH(40wt%), the etch rate of (100) plane and (111) plane decreased, but etching ratio of (100) to (111) plane increased. Consequently, the undercutting phenomenon due to etching toward (111) plane decreased and the size of V-groove could be controlled more accurately.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.127-127
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• 2011

We investigate the transparent TFTs using a transparent ZnSnO3 (ZTO)/Ag/ZTO multilayer electrode as S/D electrodes with low resistivity of $3.24{\times}10^{-5}$ ohm-cm, and high transparency of 86.29% in ZTO based TFTs. The Transparent TFTs (TTFTs) are prepared on glass substrate coated 100 nm of ITO thin film. On atomic layer deposited $Al_2\;O_3$, 50 nm ZTO layer is deposited by RF magnetron sputtering through a shadow mask for channel layer using ZTO target with 1 : 1 molar ratio of ZnO : $SnO_2$. The power of 100W, the working pressure of 2mTorr, and the gas flow of Ar 20 sccm during the ZTO deposition. After channel layer deposition, a ZTO (35 nm)/Ag (12 nm)/ZTO(35 nm) multilayer is deposited by DC/RF magnetron sputtering to form transparent S/D electrodes which are patterned through the shadow mask. Devices are annealed in air at 300$^{\circ}C$ for 30 min following ZTO deposition. Using UV/Visible spectrometer, the optical transmittances of the TTFT using ZTO/Ag/ ZTO multilayer electrodes are compared with TFT using Mo electrode. The structural properties of ZTO based TTFT with ZTO/Ag/ZTO multilayer electrodes are analyzed by high resolution transmission electron microscopy (HREM) and X-ray photoelectron spectroscopy (XPS). The transfer and output characterization of ZTO TTFTs are examined by a customized probe station with HP4145B system in are.

• Journal of Sensor Science and Technology
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• v.24 no.3
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• pp.155-158
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• 2015

In this paper, in-situ heat cooling with temperature monitoring is reported to solve thermal issues in electric vehicle (EV) batteries. The device consists of a thick graphene cooler on top of the substrate and a platinum-based resistive temperature sensor with an embedded heater above the graphene. The graphene layer is synthesized by using chemical vapor deposition directly on the Ni layer above the Si substrate. The proposed thick graphene heat cooler does not use transfer technology, which involves many process steps and does not provide a high yield. This method also reduces the mechanical damage of the graphene and uses only one photomask. Using this structure, temperature detection and cooling are conducted simultaneously using one device. The temperature coefficient of resistance (TCR) of a $1{\times}1mm^2$ temperature sensor on 1-$\grave{i}m$-thick graphene is $1.573{\times}10^3ppm/^{\circ}C$. The heat source cools down $7.3^{\circ}C$ from $54.4^{\circ}C$ to $47.1^{\circ}C$.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.465-468
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• 1998

For porous silicon layer to be used as active layer in various devices, it is necessary to be formed locally along with a designed pattern on the wafer. However, there is still no suitable masking layer to withstand against the high concentration of HF for a time of some minutes up to some hours during the anodic process effectively. In this work, we investigated the property of selectivity between p$^{+}$ and n layers to form localized porous silicon even without a mask by the difference of the anodic I-V characteristics on the doping level and doping type. The width of the pattern made in the sample was 2mm, and the formed porous silicon layer was observed by SEM to see the morphology on the cross section below the surface. As the results, it was found that the selectivity was reasonable for the pattern size over 100.mu.m.m.

• Journal of Information Display
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• v.12 no.4
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• pp.191-194
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• 2011

A symmetric-viewing inverse-twisted-nematic (ITN) liquid crystal display (LCD) with alternating alignment layers was developed using a stamping-assisted rubbing (SAR) technique. A patterned layer of a fluorinated acrylate polymer was transferred onto the first rubbed vertical-alignment layer prepared on a substrate by stamping. The fluorinated acrylate polymer provided a protective layer covering the first rubbed alignment layer during the second rubbing process, which promoted the vertical alignment of the LC molecules. The LC cell in the ITN geometry with two orthogonally rubbed alignment layers showed symmetric-viewing characteristics with fourfold symmetry. The SAR technique was shown to be a mask-free alignment method of producing multidomains for symmetric-viewing LCDs.