| 摘要: | 本研究在玻璃基材上，以磁控濺鍍系統，固定氧化鋅靶在RF 功率為150 W，鈦靶在DC功率分別為10、20和30W，鋯靶在RF 功率分別為0、25、50、60、75 和100 W下濺鍍2小時，可製備出不同鈦含量的摻鈦氧化鋅(Ti doped zinc oxides, TZO)薄膜、不同鋯含量的摻鋯氧化鋅(Zr doped zinc oxides, ZZO)薄膜以及不同鋯含量的鋯、鈦共摻氧化鋅(Zr, Ti co-doped zinc oxides, ZTZO)薄膜。經由感應耦合電漿質譜儀(inductively coupled plasma mass spectrometry
ICP-MS)分析結果顯示：鍍膜中鈦原子百分比則隨著直流濺鍍功率的增加而遞增(0.71~1.12 at.%)；而鍍膜中鋯原子百分比則隨著射頻濺鍍功率的增加而遞增(1.61~6.12 at.%)。薄膜之化學狀態經由X光光電子能譜儀(X-ray photoelectron spectrometer
XPS)分析得知，位於458.8(Ti 2p3/2) eV，為TiO2狀態之正四價鈦。位於182.2 (Zr 3d5/2)與184.5 (Zr 3d3/2) eV束縛能則屬於ZrO2正四價鋯之峰值。晶體結構方面使用XRD分析可得知ZZO、TZO和ZTZO透明導電薄膜都可改善純氧化鋅(002)峰值強度。由場發射式掃瞄式電子顯微鏡(Field Emission Scanning Electron Microscope；FE-SEM)觀察結果顯示：濺鍍所得氧化鋅薄膜皆為柱狀晶，其膜厚均約為350 nm。隨著摻雜量增加，薄膜柱狀晶直徑會有下降的現象。由原子力顯微鏡(Atomic force microscopy
AFM)分析可了解摻鈦氧化鋅薄膜與鋯共摻雜後，因晶粒細化而使得Ra與Rmax下降，導致薄膜表面更平滑。由場發射鎗穿透式電子顯微鏡(Field Emission Gun Transmission Micro-scope, FEG-TEM)結果顯示：於濺鍍沉積時，薄膜以柱狀晶成長且(002)晶面方向垂直於基板。
紫外光光電子能譜儀(Ultraviolet Photoelectron Spectroscopy, UPS)分析顯示：鋯與鈦金屬能使薄膜功函數有效地提升，但隨著載子濃度的增加功函數隨之下降。薄膜光電性質中以Zr 1.61 at. %及Ti 0.91 at.%之ZTZO薄膜具有4.18×10-3Ω-cm之最低電阻率以及在可見光穿透度為92%，其功函數為5.39 eV。薄膜光電性質中以Zr 3.46 at. %及Ti 0.71 at.%之ZTZO薄膜具有5.54×10-3Ω-cm之次低電阻率以及在可見光穿透度為91%，其功函數為5.51eV。於3.5 wt.%NaCl水溶液中由電化學法分析薄膜腐蝕特性發現：ZTZO薄膜中隨摻鋯量增加，其腐蝕電流密度減小，顯示抗蝕性增強。
Transparent conductive Zr, Ti codoped ZnO (ZTZO) films were prepared on glass substrate by three-target magnetron sputtering system in this work. The glass substrate was heated to 200°C, and the working pressure in the chamber was at 5 × 10-2 Torr. In the process of sputtering, the pure Ti target was bombarded by direct current varying in the power at 10, 20 and 30, the pure ZnO target were bombarded by radio frequency power fixed at 150 W and the pure Zr target were bombarded by radio frequency varying in the power at 0, 25, 50, 60, 75 and 100W, After sputtering for 120 minutes, the thickness of the films varying in Zr-contents was measured to be about 350 nm. The composition of ZTZO thin film was analyzed with inductively coupled plasma-mass spectrometer (ICP-MS) to show that the Zr-content increases with increasing the Zr power in the order: 0 at.% (0 W) < 1.61 at.% (25 W) < 2.76 at.% (50 W) < 3.46 at.% (60 W) < 3.82 at.% (75 W) < 6.12 at.% (100 W), and the Zr-content increases with increasing the Zr power in the order: 0 at.%(0 W) < 0.71 at.%(10 W) < 0.91 at.% (20 W) < 1.22 at.%(30 W). Through examination by X-ray photoelectron spectroscopy (XPS), the ZTZO films revealed TiO2 with binding energy of tetravalent Ti(IV) at 458.8 eV for Ti 2p3/2
ZrO2 with binding energy of tetravalent Zr(IV) at 182.2 and 184.5 eV for Zr 3d5/2 and 3d3/2, respectively. Analysis of X-ray diffraction (XRD) indicated that all the films belong to wurtzite structure textured on (002). The surface morphology and cross section of the films were examined by using field emission scanning electron microscope (FE-SEM). Through examination by atomic force microscopy (AFM), the films displayed their average surface roughness (Ra) decreased with increasing the Zr-dopant.
The carrier concentration of the films, determined by Hall effect analyzer, increased but the carrier mobility decreased with increasing the Zr-dopants so that the lowest resistivity was found at 5.54 × 10-3 Ω-cm for the ZTZO doped with 0.71 at.% Ti and 3.46 at.% Zr. Average optical transmittance of the films was analyzed higher than 90±5% by UV-vis spectra. Estimating by electrochemical measurements in 3.5 wt. % NaCl, the ZTZO films depicted their corrosion current density decreased with increasing the Zr-dopants. Therefore, ZTZOs with higher Zr-dopants were more resistant to corrosion. The features be found with the Zirconium content increase the corrosion current density is smaller, and enhanced corrosion resistance phenomenon. |
