• 한국신재생에너지학회:학술대회논문집
• /
• 2007.06a
• /
• pp.330-330
• /
• 2007

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.105-106
• /
• 2006

현재 투명 전도성 산화물로 널리 사용되고 있는 ITO등의 물질들이 갖는 문제점을 해결하기 위하여 ZnO 에 Ga이나 Al등의 불순물을 첨가하여 투명 전도성 재료로써 이에 대한 연구가 진행중에 있다. 본 연구에서는 RF 마그네트론 스퍼터법으로 Al이 첨가된 ZnO:Al Ceramic 타겟으로 Coring 1737 유리기판과 파손의 우려가 적고 유연성을 갖는 $25{\mu}m$ 두께의 polyimide(PI) 기판위에 박막을 증착하여 특성을 비교 조사하였다.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.1469-1472
• /
• 2006

We investigated the electrical and optical properties of ZnO:Al thin films as a function of the thermal process conditions. The film was prepared by RF magnetron sputtering followed by annealing in a box furnace in air. An ZnO:Al (98:2) alloy with the purity of 99.99% (3 inch diameter) was used as the target material. The electrical properties of the transparent electrode, exhibited surface oxidation as a result of rapid oxygen absorption with increasing annealing temperature. The processed ZnO:Al films and commercial ITO(indium-tin-oxide) were applied to an OLED stack to investigate the current density and luminescence efficiency. The efficiency of the device using the ZnO:Al electrode was higher than that from the device using the ITO electrode.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.05a
• /
• pp.58-61
• /
• 2005

In an effort to improve the electrical properties of ZnO:Al transparent electrode films, post-annealing treatment in hydrogen atmosphere was attempted with varying annealing time at 573 K for compatibility with typical display device fabrication processes. It was observed that carrier concentrations and mobilities increased with longer annealing time with small changes in crystallinity. This resulted in substantial decrease in resistivity from $4.80{\times}10^{-3}$ to $8.30{\times}10^{-4}{\Omega}cm$ due to increased carrier concentration. Such improvements in electrical properties are attributed to the passivation of the grain boundary surfaces. The optical properties of the films, which changed in accordance with the Burstein-Moss effect, were consistent with the observed changes in electrical properties.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.11a
• /
• pp.13-14
• /
• 2007

투명전극으로 사용되는 ITO는 우수한 전기적, 광학적 특성으로 인하여 널리 사용되고 있다. 하지만, ITO는 저온공정의 어려움과 ITO의 원료물질인 In의 수급이 불안정하여 원자재의 가격이 높고, 수소 플라즈마에 노출시 열화로 인한 광학적 특성의 변화가 문제점으로 지적되고 있다. 본 논문에서는 ITO 투명전극을 대체하기 위한 실험으로 Al 이 도핑된 ZnO(ZnO:Al) 박막을 상온에서 유리기판 위에 RF 마그네트론 스퍼터 법을 이용하여 제조하였다. 증착된 박막은 ITO물질을 대체하기 위한 투명전극으로의 응용을 위해 후 열처리를 실시하였다. 설정된 열처리 온도는 각각 400도와 300도로 설정하였고 열처리 시간에 따른 변화를 관찰하였다. 열처리된 시편은 각각 XRD, SEM, Hall, U/V 측정을 하여 변화를 관찰하였다.

• Journal of the Microelectronics and Packaging Society
• /
• v.19 no.2
• /
• pp.73-78
• /
• 2012

The chemical, electrical, and optical properties of ZnO and Al-doped ZnO films after high temperature annealing were studied. The resistivity increased significantly after annealing at $600^{\circ}C$ under $10^{-10}$ Torr atmosphere. The mechanism of the resistivity change was explored using photoemission spectroscopy and photoluminescence spectrometer. The results indicated that the amount of oxygen deficient region O-Zn bonds decreased and oxygen vacancy was decreased after the high temperature vacuum annealing. The increase in the resistivity of ZnO and Al-doped ZnO films was resulted from the decrease in carrier concentration due to a decrease in the amount of oxygen deficiency.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.21 no.9
• /
• pp.789-794
• /
• 2008

Zinc oxide (ZnO) has been widely studied for its practical applications such as transparent conduction electrodes for flat panel displays and solar cells. Especially, ZnO films show good chemical stability against hydrogen plasma, absence of toxicity, abundance in nature, and then suitable for photovoltaic applications. However, the fabrication process of thin film solar cells require a high substrate temperature and/or post heat treatment. Therefore, the layers have to withstand high temperatures, requiring an excellent stability without degrading their electronic and optical properties. In this paper, we investigated the stability of zinc oxide (ZnO) films doped with aluminum and hydrogen. Doped ZnO films were prepared by r.f. magnetron sputter and followed by heat treatment at different temperatures and for various times.

• Korean Journal of Crystallography
• /
• v.6 no.2
• /
• pp.134-140
• /
• 1995

SAW properties of SiNx/ZnO bilayer thin film structure were analyzed. ZnO thin films were deposited by rf magnetron sputter using O2 gas as an oxidizer. Structure of ZnO thin films was affected by Ar/O2 ratio. At the gas ratio of Ar/O2=67/33, the standard deviation of X-ray rocking curve of (002) preferred ZnO thin film was 2.17 degree. This value is sufficient to use ZnO thin films as an acoustic element. SAW velocity of glass/SiNx(7000Å)/Al/ZnO(5μm) structure was max. 2.2% faster than that of ZnO/glass.

• KIEE International Transactions on Electrophysics and Applications
• /
• v.3C no.4
• /
• pp.140-145
• /
• 2003

The influence of microstructure nonuniformity on the electrical characteristics of ZnO varistors was analyzed with the added amount of $Al_2$O$_3$ dopants. $Al_2$O$_3$ doping can effectively inhibit grain growth. When $Al_2$O$_3$ content is in the range between 0-0.1 %, the average grain size and the standard deviation decrease quickly and the grain growth is strongly inhibited. Therefore, it is possible to increase the microstructure uniformity by accurate addition of $Al_2$O$_3$ to the ZnO varistor. The breakdown voltage increases with the decrease of standard deviation. The greater the uniformity of the Zno varistor means the higher the global breakdown voltage. The $Al_2$O$_3$ dopants having about 0-0.023 wt% content can effectively improve the voltage ratio, and the voltage ratio reaches a minimum value of 2.32 at an $Al_2$O$_3$ content of 0.005 wt%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2003.07b
• /
• pp.857-860
• /
• 2003

Tin doped indium oxide(ITO) and Al doped zinc oxide(ZnO:Al) films, which are widely used as a transparent conductor in optoelectronic devices such as solar cell, liquid crystal display, plasma display panel, thermal heater, and other sensors, were prepared by using the capacitively coupled DC magnetron sputtering method. The electrical and optical properties of both the ITO and ZnO:Al thin films were investigated as functions of substrate temperature, working gas pressure and deposition time. ITO and ZnO:Al films with the the present experimental conditions of temperature and pressure showed resistivity of $2.36{\times}10^{-4}{\Omega}-cm,\;9.42{\times}10^{-4}{\Omega}-cm$ and transmittance of 86.28%, 90.88% in the wavelength range of the visible spectrum, respectively.