本研究主要部份是利用射頻磁控濺鍍法製備摻鑭及摻釔之鈦酸鍶薄膜，目標是使其可以導電並磊晶在單晶(100)之鈦酸鍶基板上，作為將來鐵電材料之底電極。靶材為固相燒結之含鑭及含釔的鈦酸鍶多晶陶瓷，電性測量皆為絕緣體，表示鑭及釔可能皆未實際摻入鈦酸鍶晶格之中，或摻入之後相關元素之價態未達理想值。如何從絕緣體的靶材得到會導電的薄膜，是實驗的重點所在。我們先以廉價之矽基板嘗試，做了一系列的鍍膜參數探討，優化之後用來鍍於鈦酸鍶單晶基板上。其中又分為兩類製程:其一為需要後續退火才可導電，此類製程雖然可以藉由高溫退火使薄膜導電，但會產生雜相，且無法確定是否有鈦酸鍶之相是否還存在;其二為濺鍍完成無需後續處理就可導電，其導電性足夠且無雜相生成。我們發現第二類製程的關鍵在於濺鍍功率必須超過130瓦，且導電性隨濺鍍功率增加而提升，甚至在220瓦時電阻率僅為8.1x10-5 ohm-cm。此外，由於導電之鈦酸鍶有作為熱電材料之潛力，本論文最後部分也對鑭-釔共摻之鈦酸鍶的熱電性質進行了評估。

In this study, thin films of La and Y doped SrTiO3 (STO) were deposited on the substrates of silicon and (100) oriented pure STO single crystal by the RF magnetron sputtering technique. The La or Y doping was intended to make STO conductive for a number of applications, such as bottom electrode for epitaxial growth of functional oxide films, thermoelectric conversion, etc. In order to grow the films with the desired structure and electric property, two different routes were attempted, which included: (1) deposit films at room temperature and then anneal under reduced atmosphere at high temperature (1400 ℃) to form the conductive STO phase, and (2) deposit the doped STO films at high temperature (750 ℃) to form the desired phase in-situ. In general, we found that the doped STO films grown via the in-situ route had the better phase structure than the films grown by the post-deposition annealing. In the in situ route, one of the crucial deposition parameters to achieve the epitaxial growth of La or Y doped STO films with good electric conductivity was the sputter power, which must exceed 130 W. The conductivity of the in-situ grown films was found to increase with the increase of sputter power. This outcome was due to the increased percentage of the Ti3+ ions, which was confirmed by the X-ray photoelectron spectroscopy. When the sputter power reached 220 W, the resistivity of the grown films was as low as 8.1x10-5 ohm-cm.

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