Al, Sc co-doped ZnO與ITO透明導電薄膜在3.5% NaCl中之腐蝕行為

Corrosion Behavior of Al, Sc co-doped ZnO and ITO Thin Films in 3.5% NaCl Solutions

本研究在探討Al-doped zinc oxide （AZO）、Tin-doped indium oxide （ITO）、摻雜微量鈧之AZO及經300℃熱處理1小時後之AZO透明導電氧化薄膜等，在3.5% NaCl溶液中之腐蝕行為。研究方法採用開路電位量測、線性極化掃描及交流阻抗頻譜測試（EIS）來探討它們的電化學現象，進而利用AFM表面粗糙度及SEM表面形貌來觀察其腐蝕前後之改變。
上述之透明導電氧化薄膜在3.5% NaCl中，其抗腐蝕能力由大而小依序為：經300℃熱處理之AZO > ITO > Sc co-doped AZO > AZO。摻雜微量鈧有利於AZO薄膜提升其抗腐蝕能力，其抗腐蝕性由大而小依序為：0.242 wt% > 0.134 wt% > 0.006 wt% > 0 wt%，亦即鈧摻雜量愈高，其抗蝕能力愈強。經300℃熱處理之AZO薄膜抗蝕能力佳，主要與熱處理可釋放薄膜內應力有關。

The corrosion behavior of Al, Sc co-doped zinc oxide films in 3.5% NaCl solutions was investigated. The outcome was compared with that of a commercial indium tin oxide (ITO) thin film. Electrochemical studies revealed that the corrosion resistance of the films increased in the order Al doped zinc oxide (AZO) < Sc co-doped AZO < ITO < annealed AZO (at 300 ℃ for 1 h). The AZO doped with a higher Sc-content was more resistant to corrosion. Examining the surface morphology through atomic force microscope (AFM) and scanning electron microscope (SEM), we found that the film more susceptible to corrosion exhibited a rougher surface. The higher Scdopant concentration in the film the more stable it is to maintain a higher transmittance. The most corrosion-resistant specimen (i.e., Sc-doped AZO annealed at 300 ℃ for 1 h) owed its resistance to a complete release of the lattice strain.