含氫之氧化鋅鋁透明導電膜的熱穩定性研究

Research of Thermal Stability on Hydrogen doped Al-doped Zinc Oxide Transparent Conductive Film

孫惟哲(Wei-Che Sun)

指導教授 ： 李正中

國立中央大學/理學院/光電科學研究所/碩士(2011年)

摘要

本論文利用脈衝直流磁控濺鍍法（Pulsed DC Magnetron sputtering），使用價格便宜AZO靶材鍍製AZO（Al-doped zinc oxide）薄膜，在鍍膜過程中改變氫氣氣體流量，在室溫鍍製之下探討在不同氫氣體流量下，含氫AZO薄膜之電特性以及光學特性之改變，在通入適當流量之H2的情況下鍍製之含氫AZO單層膜，其最低電阻率為4.31×10-4 Ω-cm，而其在可見光波段之平均穿透率可達85.63%，相較於未通入H2的AZO單層膜，其電阻率5.55×10-3 Ω-cm下降了許多。
在含氫AZO薄膜在高溫退火之後，導電率會大幅下降，其主要原因是氫氣跑出膜層之外，載子濃度由1.7×1021cm-3大幅降低至7.51×1020cm-3。
由於含氫AZO薄膜在高溫退火下並不穩定，因此在其上加上一層AZO保護膜，以減少氫跑出膜層的機會。擁有50nm AZO保護膜的含氫AZO在經過500℃退火之後，由5.91×10-4Ω-cm 降低至5.63×10-4Ω-cm(減低4.7%)。而不具保護膜的情況之下，4.31×10-4Ω-cm 增加到7.79×10-4Ω-cm (增加66.8%)。

關鍵字

透明導電膜 ； 氫 ； 氧化鋅鋁

並列摘要

An Al-doped zinc oxide (AZO) transparent conductive film is deposited on glass by pulsed DC magnetron sputtering. We change the H2 flows during the deposition processes to investigate the change of the electrical and optical properties through the different H2 flows deposition at room temperature. The AZO film with 30sccm H2 flows during the deposition process can have low resistivity (4.31×10-4 Ω-cm) and high average transmittance in visible region (85.63%).

The Hydrogen doped AZO films can have great electrical and optical properties. However, the hydrogen in the AZO film is unstable in high temperature. The hydrogen would leave the AZO film during the thermal treatment. After 350℃ post annealing, the resistivity increases to 1.07×10-3 Ω-cm. And the carrier concentration decreases form 1.7×1021cm-3 to 7.51×1020cm-3.

In order to increase the thermal stability of the hydrogen doped AZO films. We deposit an AZO protection film above the hydrogen doped AZO films to reduce the chance of the hydrogen departing from AZO films. The resistivity of the hydrogen doped AZO film with 50nm protection film, decreases from 5.91×10-4Ω-cm to 5.63×10-4Ω-cm (decreasing 4.7%). Comparatively, the resistivity of the hydrogen doped AZO film without protection film, increases from 4.31×10-4Ω-cm to 7.79×10-4Ω-cm (increasing 66.8%).

並列關鍵字

TCO ； AZO ； Hydrogen

參考文獻

[2] P. Frach, K. Goedicke, C. Gottfried and H. Bartzsch, “A versatile coating tool for reactive in-line sputtering in different pulse modes”, Surf. and Coat.Tech., 142–144, 628 (2001)

[3] D.G. Lim, D.H. Kim, J.K. Kim, O. Kwon, and K.J. Yang” Improved electrical properties of ZnO:Al transparent conducting oxide films using a substrate bias”, Superlattices and Microstructures, 39, 107 (2006)

[4] Shina Kuriki, and Toshitaka Kawashima, “Mechanical properties of Al2O3-doped (2 wt.%) ZnO films”,Thin Solid Films, 515, 8594 (2007)

[5] D. Horwat , A. Billard, “Effects of substrate position and oxygen gas flow rate on the properties of ZnO: Al films prepared by reactive co-sputtering”, Thin Solid Films, 515, 5444 (2007)

[6] Oliver Kluth, Gunnar Schope, Hans Werner Schock, “Comparative material study on RF and DC magnetron sputtered ZnO:Al films”, Thin Solid Films, 502, 311 (2006)