藉由置入奈米銀結構以提升超薄摻鋁氧化鋅膜層光電特性之研究

Enhancement of optoelectronic properties by inserting nano-silver structures in ultra thin Al-doped ZnO layer

吳則學(Ze-Syue Wu)

指導教授 ： 林彥勝

義守大學/電機資訊學院/電子工程學系/碩士(2014年)

摘要

在本研究中，AZO薄膜和所置入的奈米銀結構主要藉由射頻磁控濺射系統在玻璃基板上沉積。研究中首先在種子層(seed layer)摻鋁氧化鋅(ZnO：Al, AZO)進行蝕刻處理，主要目的為微粗化其表面結構來適當引導銀金屬層以奈米結構堆積分佈，達到提升薄膜導電特性並同時改善薄膜的光穿透率。製程後使用X光繞射儀(XRD)和掃描式電子顯微鏡(SEM)分析其結晶性及表面結構特性，原子力顯微鏡(AFM)量測其表面形貌及粗糙度，以載子特性量測系統與UV-VIS光譜儀分別量測薄膜結構之光電特性。研究結果顯示當奈米銀厚度控制在8nm時，且AZO種子層經由500℃退火處理後，並經0.1%硝酸(HNO3)蝕刻150秒後之整體AZO(20nm)/nano-Ag(8nm)/AZO(20nm)超薄薄膜具有最佳光電效益指數為2.84×10-2Ω-1，此時薄膜之電阻率降至4.25×10-5Ω-cm，於可見光波長範圍380nm~780nm之平均穿透率可達88.7％。

關鍵字

摻鋁氧化鋅 ； 射頻磁控濺鍍機 ； 超薄AZO膜層 ； 光電效益值

並列摘要

In this study, the AZO thin films and inserted nano-silver structures had been deposited on glass substrates by RF magnetron sputtering. The surface structure of seed layer AZO had been etched to get the post silver layer distribution to be led as nano-structure, which can improve the properties of conductivity and transmittance. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to analysis the crystallinity and surface structural characteristics. The surface roughness was measured by using an Atomic force microscopy (AFM). The optoelectronic property was measured by the UV-VIS-NIR spectroscopy and Hall measurement system. The results shown that the AZO seed layer was treated with annealing temperatures at 500℃, and after the surface had been etched by 0.1% Nitric Acid (HNO3) at 150 seconds, the resistance of AZO(20nm)/nano-Ag(8nm)/AZO(20nm) ultra-thin film is 4.25×10-5Ω-cm, and the average transmittance in visible range from 380-780 nm is about 88.7%, and the best figure of merit is 2.84×10-2Ω-1.

並列關鍵字

Aluminum-doped Zine Oxide (AZO) ； RF magnetron sputter ； AZO ultra-thin film ； Figure Of Merit (FOM)

參考文獻

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