研究目的為探討鍍膜溫度對於多晶鐵酸鉍結構與性質之影響。本實驗是利用射頻磁控濺鍍系統製備鐵酸鉍多晶薄膜成長在白金鍍覆之(100)矽晶板上，研究於攝氏300度至攝氏700度鍍膜溫度下製備之薄膜性質。研究結果指出鉍和氧之化學組成隨著鍍膜溫度升高而降低，乃因高溫氧化鉍之逸散與雜項之生成所致。於攝氏700度高溫製備之鐵酸鉍薄膜其鉍、鐵成份比低至0.53。結晶之鐵酸鉍薄膜製備於鍍膜溫度高於攝氏500度。藉由X光繞射量測分析與背向電子散射繞射結果下其(111)方向晶粒之織構係數比例皆隨鍍膜溫度由攝氏500度上升至攝氏700度而增加。藉由掃描式電子顯微鏡觀察薄膜剖面圖觀察，在攝氏500度製備之鐵酸鉍薄膜成長為柱狀晶結構，而在攝氏600度及700度製備之鐵酸鉍薄膜成長為堆疊之等軸晶結構。薄膜表面之粗糙度隨著鍍膜溫度之增加而提升。不同溫度下製備之鐵酸鉍薄膜其微結構與化學組成對於其鐵電性質與壓電性質有很大影響。其殘餘極化量與最大極化量皆在於攝氏700度製備之鐵酸鉍薄膜達最大值。量測之漏電流密度在攝氏500度製備之鐵酸鉍薄膜突然升高，而最大的漏電流密度在攝氏600度及700度製備之鐵酸鉍薄膜量測得。由於雜質的存在而導致大的漏電流，因此未能獲得完全飽和之鐵電極化遲滯曲線。在攝氏500度製備之鐵酸鉍薄膜由於其結晶性不佳，因而形成低振幅、無自極化效應之較小鐵電域。在攝氏600度及700度製備之鐵酸鉍薄膜之壓電訊號皆表現出自極化效應，且在垂直於表面皆具有強烈之振幅。在平行於表面之壓電訊號容易受到表面形貌、晶粒方向差、探針掃描方向之影響。在所有樣品中皆量測到小的水平壓電振幅訊號。由於攝氏700度製備之鐵酸鉍薄膜具有最大(111)織構係數，因此量測得最大之壓電係數。

The purpose of this study was to investigate the influence of deposition temperature on the preferred orientation and properties of BiFeO3/Pt/Ti/Si by radio frequency magnetron sputtering system. The deposition temperature were ranged from 300 to 700℃. The XPS results showed that both Bi and O fractions decreased with temperature since the volatilization of Bi2O3 and formation of impurities identified as Fe2O3 and Bi2Fe4O9 by EBSD, and the Bi/Fe ratio of specimen deposited at 700℃ was down to 0.53. Crystallized BFO thin films were obtained as the temperature higher than 500℃. Both XRD and EBSD results showed enhancement of (111)-oriented grains as deposition temperature increased from 500℃ to 700℃. The cross-sectional SEM images indicated the formation of columnar structure of grains at 500℃, and large grains with facets were observed for specimens deposited at 600 and 700℃. The higher deposition temperature, the larger surface roughness was detected. The microstructure and chemical composition of the specimens deposited at different deposition temperature strongly affected ferroelectric and piezoelectric properties. Both the largest remnant polarization (Pr) and maximum polarization (Pmax) were presented in the specimen deposited at 700℃. The leakage current suddenly increased as deposition temperature increased to 500℃ and reached the maximum in specimens deposited at 600 and 700℃. The specimen deposited at 500℃ showed low crystallinity leading to the small domains, low amplitude, and without self-poling effect. Both specimens deposited at 600℃ and 700℃ exhibit self-poling effect and strong amplitude normal to the surface. The in-plane PFM phase results were easily affected by surface morphology, misorientation, and scanning direction. Small in-plane piezoelectric amplitude were measured in all specimens. The largest piezoelectric coefficient was measured at specimen deposited at 700℃ due to the largest (111) texture coefficient.

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