銦錫氧化物-銀鈦（或銀鈦銅合金）-銦錫氧化物 三明治透明導電薄膜之開發研究

A Development of The ITO-AgTi (or AgTiCu)-ITO Transparent Conductive Thin Films

陳世偉(Shi-Wei Chen)

指導教授 ： 顧鈞豪

國立臺灣大學/工學院/材料科學與工程學研究所/博士(2007年)

https://doi.org/10.6342/NTU.2007.00623

摘要

本研究係利用三明治結構設計（ITO-Metal-ITO, IMI），製備低電阻、高透光度之透明導電薄膜，而以極薄的銀薄膜（10 nm）作為三明治透明導電薄膜的中間金屬層。三明治透明導電薄膜的導電度比單層ITO薄膜高了一個級數，可以取代ITO做為光電元件透明電極之應用。但是即使有表層ITO的保護，極薄的純銀薄膜仍然相當不穩定，在高溫或高濕度的環境中，容易發生團聚，導致三明治透明導電薄膜的導電度、透光度以及耐候性下降。因此本研究針對銀金屬層進行合金化設計，成功開發銀鈦、銀鈦銅合金，作為三明治透明導電薄膜的中間金屬層。藉由合金元素的添加，並且以固溶的形式存在，可增加銀薄膜表面結構的穩定性。並且藉由改變基板溫度、耐候性研究以及退火處理，解析銀金屬層合金化後，合金元素對銀金屬層以及IMI薄膜性質的影響行為。結果發現，固溶鈦元素的添加，可以有效穩定銀薄膜結構，抑制薄膜沈積時因為應變能釋放所導致的粗化現象，幫助銀薄膜形成層狀附著於ITO基板上；亦可抑制濕氣滲入IMI薄膜結構中所誘發的銀薄膜團聚行為；並且可以抑制高溫大氣退火時，銀/ITO薄膜發生交互擴散。如此，ITO-AgTi-ITO以及ITO-AgTiCu-ITO薄膜可具有穩定且優異的導電、透光以及耐候性。經過適當的退火處理過後，ITO-AgTiCu-ITO薄膜的透光度可提升到91.08 %，電阻率可下降至4.66 x 10-5 Ω.cm。ITO-AgTiCu-ITO薄膜的透光度與單層ITO薄膜相當，電阻率比ITO低了一個級數，並且具有優異的耐候性，相當適合取代單層ITO薄膜，應用作為光電元件的透明電極，可大幅提昇元件效率。

關鍵字

三明治透明導電薄膜 ； 銀鈦 ； 銀鈦銅 ； 耐候性

並列摘要

Using ITO-Metal-ITO (IMI) multilayer structures is the simplest and most effective way to improve the characteristics of the transparent conductive oxide (TCO). The IMI structures have quit low sheet resistance comparing with the single-layer TCO films, such as ITO, although their transmittance is slightly lower than ITO.
The characteristics of IMI films strongly depend on the intermediate layer. Silver is the best intermediate layer of IMI films, because it has higher transparency and conductivity than other metals when the film is very thin. However, pure silver films are unstable and easy to agglomerate at a high temperature. An increase in roughness will reduce the conductivity and transparency of IMI films. This study proposes to increase the stability of the Ag layer by alloying with doped Ti or Cu atoms, consequently, to increase the stability of the IMI films. Furthermore, the effect of the doping elements on the silver layer as well as the IMI film is also investigated through varying the deposition temperature, durability testing and annealing. The results indicate that, by the addition of the doping Ti atoms, the roughening of the silver film due to the relaxation of strain energy as deposition can be retarded; the agglomeration of the silver film induced by the moisture penetration can be retarded; and the interdiffusion between the silver and ITO layers when the film is annealed at a high temperature in air can also be retaeded. Therefore, the Ag-Ti film owns smooth and stable surface morphology, the ITO-AgTi-ITO and the ITO-AgTiCu-ITO films keep high conductivity, transparency and excellent durability. After annealing, the ITO-AgTiCu-ITO film owns high transparency (transparency = 91.08 %, it is close to that of the single-layer ITO), quit low resistivity (resistivity = 4.66 x 10-5 Ω.cm, it is lower than that of the single-layer ITO about one order) and excellent durability. The ITO-AgTiCu-ITO film is suitable to replace the single-layer ITO film and be applied as the transparent electrode of the optic-electric devices.

並列關鍵字

IMIITO-Metal-ITO transparent conductive thin film ； sandwich structure ； resistivity ； transparency ； durability

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