• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.56-56
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• 1999

수소화된 비정질 탄소(a-C:H0는 그 형성 조건에 따라서 여러 가지 다른 구조와 특성을 갖게 되며, 특히 DLC(diamond-like carbon)-FED(field emission display) 개발 면에서 중요하게 연구되고 있다. 본 연구에서는 a-C:H 박막을 PECVD(plasma-enhanced chemical vapor deposition) 방법으로 증착하고 주고 ESR 및 Raman 측정을 통하여 그 결과를 조사해 보았다. PECVD 증착가스는 CH4 가스를 사용하였다. 기판은 Corning 1737 glass를 사용하였고, 기판 온도는 32$0^{\circ}C$이었다. 증착 압력과 R>F. power는 각각 0.1-1 Torr 와 12-36 W 사이에서 변화되었다. ESR를 피하기 위하여, microwave power에 대한 ESR 신호 의존성을 측정하고 포화효과를 피하기 위한 Raman spectroscopy로 분석하였다. R.F.power가 증가할수록 증착속도는 0.06 nm/sec 정도까지 대체로 증가하였으나, pressure가 1 Torr 일때는 같은 R.F. power로써 증착이 일어나지 않는 경우도 발생하였다. 증착된 a-C:H 박막은 R.F.power가 증가할수록 스핀밀도의 증가가 두드러졌으며, 기타 증착가스 압력 등의 증착 조건에 따른 ESR 및 Raman 스펙트럼의 변화를 관찰하였다.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3274-3275
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• 1999

This paper presents a new method of spacer assembly using anodic bonding method which is very simple and clean. The spacer having $100{\mu}m(W){\times}2.1{\mu}m(H)$ was bonded on amorphous silicon film of anode plate. Then, the vertical-type electrode was used for assembling of spacer in high voltage field emission display. In these results, we suggested that the vertical-type electrode provided spacer alignment for high aspect ratio and more simple batch process than conventional method.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.152-152
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• 2000

차세대 평판 디스플레이로 주목박고 있는 FED는 현재 저전압 환경에서 기존의 CRT와 비슷한 해상도와 밝기를 얻지 못하고 있다. 이는 형광체 입자의 표면에 존재하는 결함, 오염, band - bonding과 같은 비발광층과 제조공정 중에 산화되거나 공기중에 노출되어 막 표면이 쉽게 오염되기 때문이다. 따라서 본 연구에서는 전기영동법으로 제작된 형광체의 효율 향상을 위해 레이저 표면 처리효과를 연구하였다. 실험에 사용한 레이저 표면처리 방법은 Nd:YAG pulse(355nm), continuous laser를 이용하였으며 레이저 power와 처리 시간을 변화시키면서 실시하였다. 형광체 막의 표면 두께 측정을 위해 Scanning Electron Microscopy(SEM), 처리된 막의 발광세기를 비교 분석하기 위해 Photoluminescence(PL), Cathodoluminescence(CL) intensity를 측정하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.446-446
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• 2010

탄소나노튜브(CNT, carbon nanotube)를 에미터 재료로 사용하여 전계방출 디스플레이 (FED, field emission display)용 캐소드(cathode)를 제작할 때 CNT paste를 구성하는 유기성 바인더를 제거하기 위한 열처리 공정은 필수적이며, 이후에 CNT의 돌출을 위한 표면처리 공정이 뒤따르게 된다. 이러한 표면처리에는 여러 가지 방법들이 있으며 캐소드 제작시 매우 중요한 부분이다. 그 이유는 열처리 과정을 거치게 되면 이물질들이 CNT를 감싸게 되는데 이는 전계방출을 방해하는 요소가 되기 때문에 이를 효과적으로 제거해주지 않으면 전계방출의 효율성이 떨어지기 때문이다. 본 연구는 스크린 인쇄법으로 제작한 CNT 캐소드의 표면처리에 관한 것으로 Tpae 방법을 이용하여 1차적으로 표면처리를 수행한 후 2차적으로 재열처리법을 이용하여 열처리 후 CNT를 감싸고 있는 이물질(ash, residue)등을 효과적으로 제거하였는지 전계방출 특성을 통하여 알아보았다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1092-1095
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• 2004

The $ZnGa_2O_4$ phosphor target is synthesized through solid-state reactions as calcine and sintering temperature in order to deposit $ZnGa_2O_4$ phosphor thin film by rf magnetron sputtering system. The $ZnGa_2O_4$ phosphor thin film is deposited on $Pt/Ti/SiO_2/Si$ substrate and prepared $ZnGa_2O_4$ Phosphor thin film is annealed by rapid thermal processor(RTP) at $750^{\circ}C$, 10 sec. The x-ray diffraction patterns of $ZnGa_2O_4$ phosphor target and thin film show the position of (311) main peak. The cathodolumincsccnce(CL) succtrums of $ZnGa_2O_4$ phosphor target show main peak of 360nm and broad bandwidth of about 180nm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.91-95
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• 1999

PED용 형광체로 사용되는 ZnCa$_2$O$_4$를 Clycine Nitrate Process로 합성하여 고상 반응법으로 합성한 ZnCa$_2$O$_4$ 분말과 비교 분석하였다. 또한 Glycine Nitrate Process로 제조시 Mn의 doping 농도를 변화시키면서 각각의 조성비에 따른 발광특성을 알아보았다. TGA 측정 결과 GNP법으로 합성된 ZnCa$_2$O$_4$ 의 경우 약 40$0^{\circ}C$ 이상에서 무게감량의 변화가 없었으며, XRD 상분석 결과 연소반응 후 이미 상형성이 이루어짐을 알 수 있었다. PL측정을 결과 GNP(GIycine Nitrate Process)로 제조된 ZnCa$_2$O$_4$분말의 발광효율이 고상 반응법으로 제조된 분말보다 우수하였으며, 균일하고 비표면적이 큰 단일상임이 관찰되었고, 더 작은 에너지와 시간으로 제조할 수 있는 장점이 있었다

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.301-302
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• 2005

The $ZnGa_2O_4$:Cr phosphor was synthesized through solid-state reactions at the various molar ratio of Cr from 0.002 % to 0.01 %. The XRD patterns show that the Cr-doped $ZnGa_2O_4$ has a (311) main peak and a spinel phase. Also the emission wavelength shills from 510 to 705 nm in comparison with $ZnGa_2O_4$:Mn when Cr is doped in $ZnGa_2O_4$. These results indicate that $ZnGa_2O_4$ phosphors hold promise for potential applications in field-emission display devices with high brightness operating in full color regions.

• Electrical & Electronic Materials
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• v.10 no.1
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• pp.33-38
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• 1997

The green emitting phosphors of the Field Emission Display(FED), Al codoped ZnGa$_{2}$O$_{4}$:Mn, were synthesized and sintered at high temperature. From X-ray diffraction measurements, it was confirmed that poly crystalline ZnGa$_{2}$O$_{4}$ and ZnAI$_{2}$O$_{4}$ solid solution coexist in Al codoped ZnGa$_{2}$O$_{4}$:Mn. Photoluminescence spectra of Al codoped ZnGa$_{2}$O$_{4}$:Mn show that the main peak position is shifted from 504 nm to 513 nm with the increase of Al concentration. The brightness was improved with the amount of Al dopant. It showed the maximum value at the doping level of 0.03 mole and then, it degraded rapidly. These results are due to the superposition of emission from . ZnGa$_{2}$O$_{4}$:Mn and ZnAI$_{2}$O$_{4}$:Mn.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.311-311
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• 2009

Carbon nanotubes (CNTs) belong to an ideal material for field emitters because of their superior electrical, mechanical, and chemical properties together with unique geometric features. Several applications of CNTs to field emitters have been demonstrated in electron emission devices such as field emission display (FED), backlight unit (BLU), X-ray source, etc. In this study, we fabricated a CNT cathode by using filtration processes. First, an aqueous CNT solution was prepared by ultrasonically dispersing purified single-walled CNTs (SWCNTs) in deionized water with sodium dodecyl sulfate (SDS). The aqueous CNT solution in a milliliter or even several tens of micro-litters was filtered by an alumina membrane through the vacuum filtration, and an ultra-thin CNT film was formed onto the alumina membrane. Thereafter, the alumina membrane was solvated by acetone, and the floating CNT film was easily transferred to indium-tin-oxide (ITO) glass substrate in an area defined as 1 cm with a film mask. The CNT film was subjected to an activation process with an adhesive roller, erecting the CNTs up to serve as electron emitters. In order to measure their luminance characteristics, an ITO-coated glass substrate having phosphor was employed as an anode plate. Our field emitter array (FEA) was fairly transparent unlike conventional FEAs, which enabled light to emit not only through the anode frontside but also through the cathode backside, where luminace on the cathode backside was higher than that on the anode frontside. Futhermore, we added a reflecting metal layer to cathode or anode side to enhance the luminance of light passing through the other side. In one case, the metal layer was formed onto the bottom face of the cathode substrate and reflected the light back so that light passed only through the anode substrate. In the other case, the reflecting layer coated on the anode substrate made all light go only through the cathode substrate. Among the two cases, the latter showed higher luminance than the former. This study will discuss the morphologies and field emission characteristics of CNT emitters according to the experimental parameters in fabricating the lamps emitting light on the both sides or only on the either side.

• Journal of the Korean Chemical Society
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• v.48 no.4
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• pp.371-378
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• 2004

The $SrGa_2S_4:Eu^{2+}$ green emitting phosphor has been studied as a luminous device for CRT (Cathode Ray Tube) or FED (Field Emission Display) and EL (Electroluminescence). This phosphor, also, is under noticed for LED (Lighting Emitting Diode) phosphor, which makes use of excitation characteristics of long wavelength region. The $SrGa_2S_4:Eu^{2+}$ phosphor was prepared generally conventional synthesis method using flux. However, this method needs high heat-treated temperature, long reaction time, complex process and harmful $H_2S$or $CS_2$ gas. In this works, therefore, we have synthesized $SrGa_2S_4:Eu^{2+}$ using SrS, $Ga_2S_3$, and EuS as starting materials, and the mixture gas of 5% H2/95% N2 was used to avoid the $H_2S$or $CS_2$. We investigated the luminescence characteristic of $SrGa_2S_4:Eu^{2+}$ phosphor prepared in various synthesis conditions, performed post-treatment and sieving process for application to LED.