• 한국전기전자재료학회논문지
• /
• 제33권2호
• /
• pp.114-117
• /
• 2020

In this study, we performed the deposition of Al thin film using a DC magnetron sputtering method. To evaluate electrical and structural properties, the growth conditions were changed in terms of two functions, namely, sputtering power ranging from 41.6 to 216 W and film growth rate ranging from 5.35 to 26.39 nm/min. The growth rate and the microstructure were characterized by a scanning electron microscopy and X-ray diffraction analysis. The plane of crystalline growth showed that the preferential (111) direction and defects due to the grain boundary increased with DC power. The resistivity of the Al film over 50 nm showed a constant value by horizontal grain growth. Our results can be applicable for the preparation of nano-templates for anodic aluminum oxide.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2003년도 춘계종합학술대회
• /
• pp.590-593
• /
• 2003

금속 산화물 박막 제작에 유효한 산화가스로 오존가스를 채택했다. 고품질의 산화 박막을 얻기 위해 고농도 오존이 필요하여 오존 농축 시스템을 구축 및 평가하였다. 이 장치는 실리카겔로 오존의 선택 흡착을 이용해, 농축 공정 시작 후 유입 농도 8.5 mol%가 검출되는 2.5 h에서 농축이 완료되고, 진공 배기로 고농도 오존가스를 생성하였으며, 성막 장치까지 가스가 공급되는 몇 분 동안은 자연분해 효과를 무시할 수 있었다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
• /
• pp.431-431
• /
• 2013

Flexible Organic Light Emitting Diode (OLED) displays are required for future devices. It is possible that plastic substrates are instead of glass substrates. But the plastic substrates are permeable to moisture and oxygen. This weak point can cause the degradation of fabricated flexible devices; therefore, encapsulation process for flexible substrate is needed to protect organic devices from moisture and oxygen. Y.G. Lee et al.(2009) [1] reported organic and inorganic multilayer structure as an encapsulation barrier for enhanced reliability and life-time.Flowable Oxide process is a low-temperature process which shows the excellent gap-fill characteristics and high deposition rate. Besides, planarization is expected by covering dust smoothly on the substrate surface. So, in this research, Bi-layer structured is used for encapsulation: Flowable Oxide Thin film by PECVD process and Al2O3 thin film by ALD process. The samples were analyzed by water vapor transmission rate (WVTR) using the Calcium test and film cross section images were obtained by FE-SEM.

• 한국전기전자재료학회논문지
• /
• 제31권5호
• /
• pp.273-277
• /
• 2018

This research introduces the sputtered IZO thin film transistor (TFT) with solution-processed $Al_2O_3$ diffusion layer. IZO is one of the most commonly used amorphous oxide semiconductor (AOS) TFT. However, most AOS TFTs have many defects that degrade performance. Especially oxygen vacancy in the active layer. In previous research, aluminum was used as a carrier suppressor by binding the oxygen vacancy and making a strong bond with oxygen atoms. In this paper, we use a solution-processed $Al_2O_3$ diffusion layer to fabricate stable IZO TFTs. A double-layer solution-processed $Al_2O_3$-sputtered IZO TFT showed better performance and stability, compared to normal sputtered IZO TFT.

• 전기학회논문지P
• /
• 제58권4호
• /
• pp.615-618
• /
• 2009

In order to apply for transparent conductive oxide(TCO), we deposited ZnO thin film on the glass at room temperature by RF magnetron sputtering method. Deposition conditions for low resistivity were optimized in our previous studies. Under the deposition condition with the RF power of 800 [W]. Sheet resistance and surface roughness of ITO and ZnO thin film were measured by Hall-effect measurement system and AFM, respectively. The sheet resistance of ITO and ZnO thin film were 7.290 [$\Omega$] and 4.882 [$\Omega$], respectively. and surface roughness were 3.634 [nm] and 0.491 [nm], respectively. Green OLED was fabricated with the structure of TPD(400 [$\AA$])/Alq3(600 [$\AA$])/LiF(5 [$\AA$])/Al(1200 [$\AA$]). Turn-on voltage of green OLED applied ITO was 7 [V] and luminance was 7,371 [$cd/m^2$]. And, Turn-on voltage of green OLED applied ZnO was 14 [V] and luminance was 6,332 [$cd/m^2$].

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2011년도 추계학술대회 초록집
• /
• pp.84.2-84.2
• /
• 2011

In this research, two thin film deposition techniques, Atomic Layer Deposition and Sputtering are carried out for the fabrication of Yittria Stabilized Zirconia electrolyte for thin film Solid Oxide Fuel Cell. Zirconium to Yittrium ratio for both cases is about 1/8. Scanning Electron Microscope(SEM) image shows that the growth rate per hour for Atomic Layer Deposition is faster than for sputtering. X-ray Photo-electron Spectroscopy(XPS) shows that the peaks of both Zirconia and Yittria shift towards higher bending energy for the case of Atomic Layer deposition and thus are more strongly attached to the substrate. Later, Nyquist plot was used to compare the conductivity of Yittria Stabilized Electrolyte for both cases. The conductivity at $300^{\circ}C$ for Atomic Layer Deposited Yittria Stabilized Zirconia is found to be $5{\times}10^{-4}S/cm$ while that for sputtered Yittria Stabilized Zirconia is $2{\times}10^{-5}S/cm$ at the same temperature. The reason for better performance for Atomic Layered YSZ is believed to be the Nano-structured layer fabrication that aids in along the plane conduction as compared to the columnarly structured Sputtered YSZ.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
• /
• pp.546-549
• /
• 2009

In this paper, we investigated the effects of different source/drain (S/D) electrode materials in thin film transistors (TFTs) based on indium-gallium-zinc oxide (IGZO) semiconductor. A transfer length and effective resistances between S/D electrodes and amorphous IGZO thin-film transistors were examined. Intrinsic TFT parameters were extracted by the transmission line method (TLM) using a series of TFTs with different channel lengths measured at a low drain voltage. The TFTs fabricated with Cu S/D electrodes showed the lowest contact resistance and transfer length indicating good ohmic characteristics, and good transfer characteristics with a field-effect mobility (${\mu}_{FE}$) of 10.0 $cm^2$/Vs.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
• /
• pp.235.2-235.2
• /
• 2015

The front transparent conductive oxide (TCO) films must exhibit good transparency, low resistivity and excellent light scattering properties for high efficiency amorphous silicon (a-Si) thin film solar cells. The light trapping phenomenon is limited due to non-uniform and low aspect ratio of the textured glass [1]. We present the low cost electrochemically deposited uniform zinc oxide (ZnO) nanorods with various aspect ratios for a-Si thin film solar cells. Since the major drawback of the electrochemically deposited ZnO nanorods was the high sheet resistance and low transmittance that was overcome by depositing the RF magnetron sputtered AZO films as a seed layer with various thicknesses [2]. The length and diameters of the ZnO nanorods was controlled by varying the deposition conditions. The length of ZnO nanorods were varied from 400 nm to $2{\mu}m$ while diameter was kept higher than 200 nm to obtain different aspect ratios. The uniform ZnO nanorods showed higher haze ratio as compared to the commercially available FTO films. We also observed that the scattering in the longer wavelength region was favored for the high aspect ratio of ZnO nanorods and much higher aspect ratios degraded the light scattering phenomenon. Therefore, we proposed our low cost and uniform ZnO nanorods for the high efficiency of thin film solar cells.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
• /
• pp.236.1-236.1
• /
• 2015

The surface morphology of front transparent conductive oxide (TCO) films is very important to achieve high current density in amorphous silicon (a-Si) thin film solar cells since it can scatter the light in a better way. In this study, we present the low cost hydrothermal deposited uniform zinc oxide (ZnO) nano-flower structure with various aspect ratios for a-Si thin film solar cells. The ZnO nano-flower structures with various aspect ratios were grown on the RF magnetron sputtered AZO films. The diameters and length of the ZnO nano-flowers was controlled by varying the annealing time. The length of ZnO nano-flowers were varied from 400 nm to $2{\mu}m$ while diameter was kept higher than 200 nm to obtain different aspect ratios. The ZnO nano-flowers with higher surface area as compared to conventional ZnO nano structure are preferred for the better light scattering. The conductivity and crystallinity of ZnO nano-flowers can be enhanced by annealing in hydrogen atmosphere at 350 oC. The vertical aligned ZnO nano-flowers showed higher haze ratio as compared to the commercially available FTO films. We also observed that the scattering in the longer wavelength region was favored for the high aspect ratio of ZnO nano-flowers. Therefore, we proposed low cost and vertically aligned ZnO nano-flowers for the high performance of thin film solar cells.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
• /
• pp.98-98
• /
• 1999

Highly transparent and conducting tin-doped indium oxide (ITO) films were deposited on polycarbonate substrate by ion-assited deposition. Low substrate temperature (<10$0^{\circ}C$) was maintained during deposition to prevent the polycarbonate substrate from be deformed. The influence of ion beam energy, ion current density, and tin doping, on the structural, electrical and optical properties of deposited films was investigated. Indium oxide and tin-doped indium oxide (9 wt% SnO2) sources were evaporated with assisting ionized oxygen in high vacuum chamber at a pressure of 2$\times$10-5 torr and deposition temperature was varied from room temperature to 10$0^{\circ}C$. Oxygen gas was ionized and accelerated by cold hallow-cathode type ion gun at oxygen flow rate of 1 sccm(ml/min). Ion bea potential and ion current of oxygen ions was changed from 0 to 700 V and from 0.54 to 1.62 $\mu$A. The change of microstructure of deposited films was examined by XRD and SEM. The electrical resistivity and optical transmittance were measured by four-point porbe and conventional spectrophotometer. From the results of spectrophotometer, both the refractive index and the extinction coefficient were derived.