• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
• /
• pp.198.1-198.1
• /
• 2016

Organic light-emitting diode (OLED) displays have promising potential to replace liquid crystal displays (LCDs) due to their advantages of low power consumption, fast response time, broad viewing angle and flexibility. Organic light emitting materials are vulnerable to moisture and oxygen, so inorganic thin films are required for barrier substrates and encapsulations.[1-2]. In this work, the silicon-based inorganic thin films are deposited on plastic substrates by plasma-enhanced chemical vapor deposition (PECVD) at low temperature. It is necessary to deposit thin film at low temperature. Because the heat gives damage to flexible plastic substrates. As one of the transparent diffusion barrier materials, silicon oxides have been investigated. $SiO_x$ have less toxic, so it is one of the more widely examined materials as a diffusion barrier in addition to the dielectric materials in solid-state electronics [3-4]. The $SiO_x$ thin films are deposited by a PECVD process in low temperature below $100^{\circ}C$. Water vapor transmission rate (WVTR) was determined by a calcium resistance test, and the rate less than $10.^{-2}g/m^2{\cdot}day$ was achieved. And then, flexibility of the film was also evaluated.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
• /
• pp.236-236
• /
• 2011

Silicon oxynitride (SiON) was deposited for gas barrier film on polyethylene terephthalate (PET) using octamethylycyclodisiloxane (Si4O4C8H24, OMCTS) precursor by plasma enhanced chemical vapor deposition (PECVD) at low temperature. The ion flux and substrate temperature were measured by oscilloscope and thermometer. The chemical bonding structure and barrier property of films were characterized by Fourier transform infrared (FT-IR) spectroscopy and the water vapor transmission rate (WVTR), respectively. The deposition rate of films increases with RF bias and nitrogen dilution due to increase of dissociated precursor and nitrogen ion incident to the substrate. In addition, we confirmed that the increase of nitrogen dilution and RF bias reduced WVTR of films. Because, on the basis of FT-IR analysis, the increase of the nitrogen gas flow rate and RF bias caused the increase of the C=N stretching vibration resulting in the decrease of macro and nano defects.

• 한국식품과학회지
• /
• 제21권2호
• /
• pp.252-257
• /
• 1989

OPP/PVDC 도포/LDPE 복합 필름과 Nylon/LDPE복합 필름을 사용하여 비엔나 소시지를 포장하며 품질수명을 비교한 결과는 다음과 같다. 두 복합 필름의 투습도와 가스투과도는 PVDC 도포 필름이 현저히 적었다. Nylon복합 필름은 가로, 세로 사이의 신장율이 비슷했으나 PVDC 도포 필름은 가로, 세로의 신장율이 4.5배 정도 차이가 있었다. 비엔나 소시지의 Critical Quality Index로서 VBN 이 더 적합했고 이 VBN 변화치로부터 구한 반응 속도상수로부터 $Q_{10}$치를 계산하여 예측한 품질수명은 $15^{\circ}C$ 저장의 경우 Nylon 복합 필름은 25일, PVDC 도포 필름은 31일, $5^{\circ}C$ 저장의 경우 Nylon복합 필름은 32일, PVDC도포 필름은 41일로 나타났다. PVDC도포 필름의 품질수명이 6일에서 9일정도 더 길었다.

• 한국대기환경학회지
• /
• 제20권3호
• /
• pp.411-419
• /
• 2004

Titania particles are widely used as a photocatalyst to treat various contaminants in air and water. Titania particles were formed by vapor-phase oxidation of titanium tetraisopropoxide (TTIP) in a tube furnace between 773 and 1,273 K. The effect of process variables such as furnace temperature, flow rate of carrier air, and flow rate of sheath air on powder size and phase characteristics was investigated using a scanning mobility particle sizer (SMPS), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The size distribution of synthesized titania particles was characterized with mode diameter and peak concentration. The mode diameter ranging from 20 to 80 nm decreased with increasing flow rates of sheath air and carrier air, and increased with increasing furnace temperature. The peak concentration increased with increasing flow rates of sheath air and carrier air The best synthetic condition for high production rate can be derived from the experimental data set represented by mode diameter and peak concentration. The crystal structure of synthesized titania particles was found to be anatase phase, ensuring high photocatalytic potential.

• 한국전기전자재료학회논문지
• /
• 제23권5호
• /
• pp.397-402
• /
• 2010

In this paper, we studied WVTR(water vapor transmission rate) properties of $Si_3N_4$ thin film that was deposited using TCP-CVD (transformer coupled plasma chemical vapor deposition) method for the possibility of OLED(organic light emitting diode) encapsulation. Considering the conventional OLED processing temperature limit of below $80^{\circ}C$, the $Si_3N_4$ thin films were deposited at room temperature. The $Si_3N_4$ thin films were prepared with the process conditions: $SiH_4$ and $N_2$, as reactive gases; working pressure below 15 mTorr; RF power for TCP below 500 W. Through MOCON test for WVTR, we analyzed water vapor permeation per day. We obtained that WVTR property below 6~0.05 gm/$m^2$/day at process conditions. The best preparation condition for $Si_3N_4$ thin film to get the best WVTR property of 0.05 gm/$m^2$/day were $SiH_4:N_2$ gas flow rate of 10:200 sccm, working pressure of 10 mTorr, working distance of 70 mm, TCP power of 500 W and film thickness of 200 nm. respectively. The proposed results indicates that the $Si_3N_4$ thin film could replace metal or glass as encapsulation for flexible OLED.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
• /
• pp.516-516
• /
• 2013

Flexible Display를 제작하기 위해서는 유기소자를 보호하는 보호막이 필요하다. 유기소자는 산소 및 수분에 매우 취약하기 때문에 장수명을 확보하기 위해서는 추가적인 보호층이 필요하다. 본 논문에서는 이를 위해 Encapsulation 중 한 방법인 Barrier Film을 제작하고 그에 따른 광학적인 특성 및 수분 투습율을 조사하였다. Barrier film의 광학적 분석 방법으로는 XPS, SEM, AFM, Transmittance를 측정하였으며, XPS는 박막내의 화학적인 결합을 알기 위해서 사용되었고, SEM은 박막의 두께 및 박막내의 결함을 파악하고자 하였다. SEM을 통해 증착속도가 32.6 nm/m이라는 것을 관찰할 수 있었다. AFM을 통해 증착된 박막의 표면 거칠기를 파악하였다. Transmittance는 PET 기판을 사용하여 가시광 영역에서 80%이상의 투과도를 나타내었다. PECVD 장비를 사용하여 SiH4, NH3, N2가스를 사용하여 PET 필름 위에 박막을 증착하였으며, 유량을 10~400 sccm 내에서 변화시키고, RF Power는 각각 30~300 W 15분간 증착하였다. 제작된 보호막의 수분투습율은 $2{\times}10{_2}^{-2}g/m^2/day$ 이하의 값을 나타내었다.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
• /
• pp.420-423
• /
• 2008

The characteristics of $Al_2O_3/Ag/Al_2O_3$ multilayer passivaton prepared by twin target sputtering (TTS) system for organic light emitting diodes. The $Al_2O_3/Ag/Al_2O_3$ multilayer thin film passivation on a PET substrate had a high transmittance of 86.44 % and low water vapor transmission rate (WVTR) of $0.011\;g/m^2$-day due to the surface plasmon resonance (SPR) effect of Ag interlayer and effective multilayer structure for preventing the intrusion of water vapor. Using synchrotron x-ray scattering and field emission scanning electron microscope (FESEM) examinations, we investigated the growth behavior of Ag layer on the $Al_2O_3$ layer to explain the SPR effect of the Ag layer. This indicates that an $Al_2O_3/Ag/Al_2O_3$ multilayer passivation is a promising thin film passivation scheme for organic based flexible optoelectronics.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
• /
• pp.234.2-234.2
• /
• 2014

Organic light emitting diode (OLED) is considered as the next generation flat panel displays due to its advantages of low power consumption, fast response time, broad viewing angle and flexibility. For the flexible application, it is essential to develop thin film encapsulation (TFE) to protect oxidation of organic materials from oxidative species such as oxygen and water vapor [1]. In many TFE research, the inorganic film by atomic layer deposition (ALD) process demonstrated a good barrier property. However, extremely low throughput of ALD process is considered as a major weakness for industrial application. Recently, there has been developed a high throughput ALD, called 'spatial ALD' [2]. In spatial ALD, the precursors and reactant gases are supplied continuously in same chamber, but they are separated physically using a purge gas streams to prevent mixing of the precursors and reactant gases. In this study, the $Al_2O_3$ thin film was deposited by spatial ALD process. We characterized various process variables in the spatial ALD such as temperature, scanning speed, and chemical compositions. Water vapor transmission rate (WVTR) was determined by calcium resistance test and less than $10-^3g/m^2{\cdot}day$ was achieved. The samples were analyzed by x-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscope (FE-SEM).

• 반도체디스플레이기술학회지
• /
• 제16권1호
• /
• pp.1-5
• /
• 2017

Encapsulation of organic based devices is essential issue due to easy deterioration of organic material by water vapor. Thin layer of encapsulation film is required to preserve transparency yet protecting materials in it. Atomic layer deposition(ALD) is a promising solution because of its low temperature deposition and quality of the deposited film. $Al_2O_3$ or $Al_2O_3/TiO_2/Al_2O_3$ multilayer film has shown excellent environmental protection characteristics despite of thin thicknesses of the films. $Al_2O_3/TiO_2/Al_2O_3$ multilayer and 1.5 dyad layer of $Al_2O_3/polymer/Al_2O_3$ deposited by ALD was measured to have water vapor transmittance rate(WVTR) well below the detection limit($5.0{\times}10^{-5}g/m^2day$) of MOCON Aquatran 2 equipment.

• 한국진공학회지
• /
• 제19권6호
• /
• pp.495-500
• /
• 2010

원자층 증착법(ALD: atomic layer deposition)을 이용하여 PES (poly (ether sulfon)) 기판위에 증착 온도, 플라즈마 파워에 따라 $Al_2O_3$와 $TiO_2$ 박막을 증착했다. 공정 조건에 따라 $Al_2O_3$와 $TiO_2$ 박막의 밀도, 탄소의 함유량이 달라지는 것을 알 수 있었으며, 공정 조건을 변화시켜 고밀도의 박막을 얻을 수 있었다. 플라즈마에 의한 PES 기판 손상을 막기 위해 buffer layer를 도입했으며, 또한 박막 내부 결함에 의한 수분 투과를 지연 또는 막기 위해 다층 구조를 증착했다. 이를 분석하기 위해 MOCON test를 이용해 투습률을 조사하였다. 플라스틱 기판에 다층 구조의 무기물 보호막을 적용했을 시 플라스틱 기판의 투습률 특성이 개선되었으며, 수분 투과에 대한 activation energy 또한 증가하는 것을 알 수 있었다.