• 한국광학회지
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• 제17권1호
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• pp.104-109
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• 2006

동시 스퍼터링법으로 $TiO_2$ 박막과 구리를 도핑한 Cu/$TiO_2$ 박막을 제작하고, 금속의 도핑과 열처리 온도에 따른 구조적, 광학적, 광분해 특성을 조사하였다. XRD 측정 결과 구리 도핑의 경우에 입자의 결정 크기가 증가하였으며, SEM 결과 입자들의 크기가 균일하고 입자들의 뭉침이 더 작은 것을 확인 할 수 있었다. $900^{\circ}C$에서 열처리한 박막의 흡수단은 아나타제에서 루타일로의 상전이에 의해 밴드갭의 변화로 장파장 영역으로 이동하였고, 또한 입자 크기 증가에 따라 투과율이 급격히 감소하였다. Cu/$TiO_2$ 박막들은 순수$TiO_2$ 박막보다 광분해 특성이 더 우수하였다.

• 한국세라믹학회지
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• 제33권3호
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• pp.313-320
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• 1996

We have fabricated an in-plane aligned a-axis oriented YBa2Cu3O7-x (a-YBCO) thin film on a LaSrGaO4(100) substrate with a PrBa2Cu3O7-x(PBCO) template layer by two step plused laser deposition using 308 nm XeCl excimer laser. A YBCO layer and PBCO layer grown at low temperatures were used as template layers. We have investigated the effect of the deposition temperature of template layers on the superconducting and struc-tural properties of in-plane aligned a-YBCO thin films. An optimal deposition temperature of the PBCO template layers was 630. In-plane aligned a-YBCO thin films showed an anisotropy ratio in resistivity of 11.5 and a zero resistance temperature of 88 K.

• 마이크로전자및패키징학회지
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• 제20권1호
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• pp.27-31
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• 2013

Copper-oxide (CuO) thin films were prepared by reactive sputtering of Cu onto Si wafers and characterized using a statistical design of experiments approach. The most significant factor in controlling the electrical resistivity and deposition rate was determined to be the $O_2$ fraction. The deposited CuO thin films were characterized in terms of their physical and chemical properties, using X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), X-ray diffraction (XRD), and 4-point resistance measurements. The deposited copper thin films were characterized by XPS and XRD analyses to consist of $Cu^{2+}$. The CuO thin films of highest resistivity exhibited superior rectifying responses with regard to n-type Si wafers, with a current ratio of $3.8{\times}10^3$. These superior responses are believed to be associated with the formation of a charge-depletion region originating from the p-type CuO and n-type Si materials.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.587-588
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• 2005

Ozone is useful oxidizing gas for the fabrication of BSCCO thin films. In order to obtain high quality oxide BSCCO thin films, higher ozone concentration is necessary. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In this paper oxidation property was evaluated relation between oxide gas pressure and inverse temperature(CuO reaction). The obtained condition was formulated by the fabrication of Cu metal thin film by co-deposition using the Ion Beam Sputtering method. Because the CuO phase peak appeared at the XRD evaluation of the CuO thin film using ozone gas, this study has succeeded in the fabrication of the CuO phase at $825^{\circ}C$.

• ETRI Journal
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• 제35권6호
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• pp.1156-1159
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• 2013

We investigate the characteristics of $Cu_2O$ thin films deposited through the addition of $N_2$ gas. The addition of $N_2$ gas has remarkable effects on the phase changes, resulting in improved electrical and optical properties. An intermediate phase ($6CuO{\cdot}Cu_2O$) appears at a $N_2$ flow rate of 1 sccm, and a $Cu_2O$ (200) phase is then preferentially grown at a higher feeding amount of $N_2$. The optical and electrical properties of $Cu_2O$ thin films are improved with a sufficient $N_2$ flow rate of more than 15 sccm, as confirmed through various analyses. Under this condition, a high bandgap energy of 2.58 eV and a conductivity of $1.5{\times}10^{-2}$ S/cm are obtained. These high-quality $Cu_2O$ thin films are expected to be applied to $Cu_2O$-based heterojunction solar cells and optical functional films.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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• pp.110-113
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• 2005

Ozone is useful oxidizing gas for the fabrication of BSCCO thin films. In order to obtain high quality oxide BSCCO thin films, higher ozone concentration is necessary. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In this paper oxidation property was evaluated relation between oxide gas pressure and inverse temperature(CuO reaction). The obtained condition was formulated by the fabrication of Cu metal thin film by co-deposition using the Ion Beam Sputtering method. Because the CuO phase peak appeared at the XRD evaluation of the CuO thin film using ozone gas, this study has succeeded in the fabrication of the CuO phase at $825^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• 제32권9호
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• pp.3395-3399
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• 2011

Copper oxide thin films were synthesized by reactive radio frequency magnetron sputtering at different oxygen gas ratios. The chemical and physical properties of the thin films were investigated by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). XPS results revealed that the dominant oxidation states of Cu were $Cu^0$ and $Cu^+$ at 0% oxygen ratio. When the oxygen ratios increased above 5%, Cu was oxidized as CuO as detected by X-ray induced Auger electron spectroscopy and the $Cu(OH)_2$ phase was confirmed independent of the oxygen ratio. The valence band maxima were $1.19{\pm}0.09$ eV and an increase in the density of states was confirmed after formation of CuO. The thickness and roughness of copper oxide thin films decreased with increasing oxygen ratio. The crystallinity of the copper oxide films changed from cubic Cu through cubic $Cu_2O$ to monoclinic CuO with mean crystallite sizes of 8.8 nm (Cu) and 16.9 nm (CuO) at the 10% oxygen ratio level.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.118-118
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• 2011

The Nano-Floating Gate Memory(NFGM) devices with ZnO:Cu thin film embedded in Al2O3 and AlOx-SAOL were fabricated and the electrical characteristics were evaluated. To further improve the scaling and to increase the program/erase speed, the high-k dielectric with a large barrier height such as Al2O3 can also act alternatively as a blocking layer for high-speed flash memory device application. The Al2O3 layer and AlOx-SAOL were deposited by MLD system and ZnO:Cu films were deposited by ALD system. The tunneling layer which is consisted of AlOx-SAOL were sequentially deposited at $100^{\circ}C$. The floating gate is consisted of ZnO films, which are doped with copper. The floating gate of ZnO:Cu films was used for charge trap. The same as tunneling layer, floating gate were sequentially deposited at $100^{\circ}C$. By using ALD process, we could control the proportion of Cu doping in charge trap layer and observe the memory characteristic of Cu doping ratio. Also, we could control and observe the memory property which is followed by tunneling layer thickness. The thickness of ZnO:Cu films was measured by Transmission Electron Microscopy. XPS analysis was performed to determine the composition of the ZnO:Cu film deposited by ALD process. A significant threshold voltage shift of fabricated floating gate memory devices was obtained due to the charging effects of ZnO:Cu films and the memory windows was about 13V. The feasibility of ZnO:Cu films deposited between Al2O3 and AlOx-SAOL for NFGM device application was also showed. We applied our ZnO:Cu memory to thin film transistor and evaluate the electrical property. The structure of our memory thin film transistor is consisted of all organic-inorganic hybrid structure. Then, we expect that our film could be applied to high-performance flexible device.----못찾겠음......

• 한국세라믹학회지
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• 제28권12호
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• pp.1005-1011
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• 1991

Y-Ba-Cu-O thin films were in-situ fabricated on LaAlO3(100) substrates using the second harmonics of a pulsed Nd:YAG laser. Thin films were deposited under 200 (mtorr) of oxygen atmosphere, when the substrate temperature was changed between 67$0^{\circ}C$ and 82$0^{\circ}C$. After deposition, the films were in-situ annealed at 50$0^{\circ}C$ under 2/3 bar of oxygen pressure. We showed that the deposition temperature affects the formation of superconducting phase, the resistance, and the surface morphology. The Y-Ba-Cu-O thin films deposited at 76$0^{\circ}C$ show the zero resistance critical temperature of 85 K.

• 한국세라믹학회지
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• 제28권3호
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• pp.243-251
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• 1991

High-Tc YBa2Cu3O7-x superconducting thin films have been prepared by single-target off-axis RF magnetron sputtering. Optimal ratio of Y : Ba : Cu of the single-target was determined as 1 : 1.65 : 3.35 in order to obtain the stoichiometric films. Tc, crystalline phase, and microstructures of the surface and cross-section of the ex-situ YBa2Cu3O7-x thin films on MgO(100) had a Tc, zero of 80K, and the films on LaAlO3/Si had a Tc, on-set of 90 K and a Tc, zero of 70 K.