本研究使用自行合成之摻鋁氧化鋅溶膠，利用刮刀塗佈摻鋁之氧化鋅膜於玻璃基材上，再以超臨界二氧化碳加以乾燥。由於乾燥過程可有效去除溶劑，因而避免溶劑揮發所導致氧化鋅膜之破裂，解決一般傳統製程中無法一次製備高於1 μm膜厚度的問題。本研究的主要目標為提供一環保、簡單及低成本的製程以製備攙鋁之氧化鋅薄膜。由實驗結果，可得最適化的實驗條件為:在超臨界二氧化碳中進行乾燥，操作溫度為40 oC及壓力為2100 psi；二氧化碳流率為800 mL/min；乾燥時間為1 hr；洩壓時間維持於15 hr 以上。乾燥後進行500 oC煅燒2 hr，接著以525 oC進行10% H2 (in N2)處理45 min，熱處理後利用高壓含浸法進行膜後處理。在此製備程序中，一次塗佈即可得到不破裂的厚度為1280 nm之氧化鋅膜，三倍於傳統製備方法中一次所能得到之最高膜厚(約400 nm)，所製備之氧化鋅膜的透光度亦可達到93%以上，片電阻值為2.05×105 Ω/□。

Aluminum doped zinc oxide (AZO) films on glass were formed by blade coating of the prepared solution containing well dispersed in 4~6 nm AZO particles first and followed by supercritical CO2 drying and calcination at 500 ℃ for 2 h. After a systematic study of the effects of various operation variables on supercritical CO2 drying, the AZO films with a thickness more than 1000 nm without any cracks in one preparation step were found to form at the most appropriate operation conditions of a temperature of 40 ℃, a pressure of 2100 psi, a CO2 flow rate of 800 mL/min, and a drying period of 2 h. A chemical plating method was used to infuse more AZO into the pores of the film after the calcination of the AZO film treated with supercritical CO2 drying. The transmittance of the finalized film could be as high as 93% and the conductivity was of 2.05*105 Ω/□.

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