알루미나로 코팅된 지르코니아를 이용한 수산화아파타이트의 복합화

학위논문(석사)--서울대학교 대학원 :무기재료공학과,1998.Maste

수산화아파타이트, 지르코니아, 알루미나를 재료로 하는 생체세라믹 복합체의 제조와 특성 분석

Thesis (doctoral)--서울대학교 대학원 :재료공학부,2003.Docto

Influence of Substrate Bias Voltage on the Electrical and Optical Properties of IWO Thin Films

Transparent conductive tungsten (W) doped indium oxide (In2O3; IWO) films were deposited at different substrate bias voltage (-Vb) conditions at room temperature on glass substrates by radio frequency (RF) magnetron sputtering and the influence of the substrate bias voltage on the optical and electrical properties was investigated. As the substrate bias voltage increased to -350 Vb, the IWO films showed a lower resistivity of 2.06 × 10-4 Ωcm. The lowest resistivity observed for the film deposited at -350 Vb could be attributed to its higher mobility, of 31.8 cm2/Vs compared with that (6.2 cm2 /Vs) of the films deposited without a substrate bias voltage (0 Vb). The highest visible transmittance of 84.1 % was also observed for the films deposited at the -350 Vb condition. The X-ray diffraction observation indicated the IWO films deposited without substrate bias voltage were amorphous phase without any diffraction peaks, while the films deposited with bias voltage were polycrystalline with a low In2O3 (222) diffraction peak and relatively high intensity (431) and (046) diffraction peaks. From the observed visible transmittance and electrical properties, it is concluded that the opto-electrical performance of the polycrystalline IWO film deposited by RF magnetron sputtering can be enhanced with effective substrate bias voltage conditions

Effect of Ag interlayer on the optical and electrical properties of ZnO thin films

ZnO single layer (60 nm thick) and ZnO with Ag interlayer (ZnO/Ag/ZnO; ZAZ) films were deposited on the glass substrates by using radio frequency (RF) and direct current (DC) magnetron sputter to evaluate the effectiveness of Ag interlayer on the optical visible transmittance and the conductivity of the films. In the ZAZ films, the thickness of ZnO layers was kept at 30 nm, while the Ag thickness was varied as 5, 10, 15 and 20 nm. In X-ray diffraction (XRD) analysis, ZnO films show the (002) diffraction peak and ZAZ films also show the weak ZnO (002) peak and Ag (111) diffraction peak. As a thickness of Ag interlayer increased to 20nm, the grain size of the Ag films enlarged to 11.42 nm and the optical band gap also increased from 4.15 to 4.22 eV with carrier concentration increasing from 4.9 to 10.5×1021 cm-3. In figure of merit measurements, the ZAZ films with a 10 nm thick Ag interlayer showed the higher figure of merit of 4.0×10-3 Ω-1 than the ZnO single layer and another ZAZ films. From the experimental result, it is assumed that the Ag interlayer enhanced effectively the opto-electrical performance of the ZAZ films

Influence of Ag interlayer Thickness on the Optical, Electrical and Mechanical Properties of Ti-doped In2O3/Ag/Ti-doped In2O3 Multilayer Flexible Transparent Conductive Electrode

Transparent and conductive Ti-doped In2O3 (TIO)/Ag/Ti-doped In2O3 (TAT) multilayer films were deposited on colorless poly imide (CPI) substrates by direct current (DC) and radio frequency (RF) magnetron sputtering at room temperature. During deposition the thickness of both the top and bottom TIO layer was fixed at 30 nm, while the thickness of the Ag interlayer was varied, to 5, 10, and 15 nm, to enhance the optical, electrical and mechanical properties of the films. In the XRD analysis the TIO films did not show any characteristic peaks in the diffraction pattern. The 10 nm thick Ag inter layer showed some characteristic peaks of Ag (111), (200), (220) and (311), respectively, and the grain size of the Ag interlayer enlarged as Ag thickness increased. To investigate the most efficient Ag interlayer thickness, a figure of merit (FOM) based on the opto-electrical performance of the transparent conducting films was compared. The films with a 10 nm thick Ag interlayer exhibited a higher FOM of 1.71 x 10(-2) O-1 than the other films. When the radius of the film's curvature was reduced to 1.7 mm, the TIO single layer films showed a 13 times increase in sheet resistance, while the TAT (30/10/30 nm) films showed an insignificant change in sheet resistance. From the observed results, it was concluded that the Ag interlayer in the TAT multilayer films enhanced the opto-electrical performance of the films and also acted as a potent bridge which assured the high flexibility endurance of the films

Effect of Electron Irradiation on the Optical and Electrical Properties of TIO/Ag/TIO Films

The influence of electron irradiation energy on the optical and electrical properties of TIO/Ag/TIO films has been investigated. These films prepared with RF and DC magnetron sputtering; they show the lowest resistivity of 4.71 × 10?? Ωcm. The visible transmittance also increased with the electron irradiation energy. The film irradiated at 700 eV shows 83.71% of visible transmittance. In addition, the electron irradiated films at 700 eV show a lower RMS roughness of 63.54 nm. Comparing the figure of merit, we conclude that the visible transmittance and electrical resistivity of the films are dependent on the electron irradiation energy; moreover, the opto-electrical performance of the film is enhanced by electron irradiation