本研究利用傳統固態反應法並藉由添加不同混合比例的氧化鑭 (La2O3) 或氧化釤 (Sm2O3) 製備含鑭及含釤之鈦酸鋇靶材，主要以添加物的混合莫爾比例來區分，依序為1%La、3%La、5%La、7%La和1%Sm、3%Sm、5%Sm、7%Sm，並且利用射頻磁控溅鍍法來沉積其相對應的薄膜。所得之薄膜經成分分析以添加物含量之原子百分比可表示為0.1La、1.4La、2.4La、2.8La和0.1Sm、1.0Sm、1.5Sm、2.2Sm。
此研究重點是討論在不同的退火溫度和薄膜中不同含量及種類的添加物對鈦酸鋇薄膜之結構和電性之間的相互關係。藉由X光繞射的量測證實初鍍薄膜為非晶質狀態，經由快速退火處理後，可得到結晶性較佳之薄膜。根據原子力顯微鏡掃描之結果，膜表面粗糙度隨著退火溫度的增加而增加，也隨著添加量的增加而減少。此外，在鍵結能的分析顯示在少量添加時，鑭和釤分別佔據鈦酸鋇晶格中A位置和B 位置；反之當添加量較多時，會形成氧化鑭和氧化釤並存在鈦酸鋇的結構中。在電性方面，介電常數隨著退火溫度增加而增加，是由於較佳的結晶性和較大的晶粒所造成；而漏電流大小和添加物種類有相關性，其機制由低電場到高電場分別為Schottky, Poole-Frankel, and Tunneling emission。
此外，我們也將鈦酸鋇薄膜沉積至以銅錸合金[Cu(ReNx)]為電極的矽基板上，在不同退火溫度下，探討銅合金電極和鈦酸鋇薄膜之間的界面、電性行為並觀察銅合金電極和矽基板之間的熱穩定性。依聚焦離子束、穿透式電子顯微鏡的結果得知當退火溫度升高至873K時，在鈦酸鋇和銅合金之間仍無明顯的反應。由X光繞射和電子能譜圖結果得知當退火溫度升高至973K時，銅錸合金薄膜仍以金屬銅的結晶相為主，只有極少量的氧化銅生成，並無發現銅矽化合物，顯示此合金具有良好的熱穩定性並適合當作金屬/絕緣體/金屬結構之電極材料。
然而在近十年對鈦酸鋇的研究中，主要注重於探討正方晶結構的鈦酸鋇之介電、鐵電特性，對於高溫相六方晶結構的鈦酸鋇少有報導。本實驗成功的利用射頻磁控溅鍍法製造含鈷之鈦酸鋇薄膜並經由還原氣氛下之退火處理，最後經X光繞射量測證實為六方晶結晶結構之鈦酸鋇。本實驗採用在還原氣氛下的退火處理，目的是為了使氧氣缺乏，並且依據缺陷化學的理論，受體添加也能達到與還原處理相同的目的。

200-nm-thick La- and Sm-doped BaTiO3 thin films with A/B ratio of unity fabricated by magnetron sputtering on the Pt/Ti/SiO2/Si substrate have been characterized. The effects of post-annealing and the amount of dopant on structure and electrical properties were studied. X-ray diffraction studies reveal that the films annealed at 750˚C show tetragonal BaTiO3 crystal structure without any detectable second phase formation. X-ray photoelectron spectroscopy results confirm that La substitutes the A site and Sm is in the B site in lightly doped films. La2O3 or Sm2O3 is present in the BaTiO3 structure when the dopant content is more than 1.4 at. % La or 1.0% Sm. The permittivity increases with increasing annealing temperature up to 750˚C due to the coarse grains and better crystallinity. The leakage current property is found to vary with the type of dopant.
In addition, we attempted to deposit BaTiO3 film on the Si/SiO2/TaN/Cu(ReNx) substrate to investigate that a stable Cu-based contact stack to overcome Cu diffusion and oxidation problems encountered during the high dielectric constant oxide thin-film device integration. Our Si/SiO2/TaN/Cu(ReNx) contact stack is also beneficial from the barrierless scheme for improving the BaTiO3 thin-film device performance. Interfacial investigation reveals no extensive interaction between BaTiO3 and barrierless Cu contact stack after annealing up to 873 K. BaTiO3 on the low resistivity (4.5 μΩ-cm) Cu-based contact stack behaves fairly similar to that on the Pt counterpart as the symmetry of the leakage current is obtained using different work function contacts (Cu and Pt). As Cu is compatible with integrated circuit processing, our barrierless Cu(ReNx)/BaTiO3 contact stack is readily applicable for integration with Si-based devices.
Numerous researches have reported the dielectric and ferroelectric properties of tetragonal-phase BaTiO3 in past decades, whereas very few researchers have investigated the physical properties of hexagonal-phase BaTiO3. In this study, the hexagonal structure of Co-doped BaTiO3 thin films were successfully fabricated on various substrates by magnetron sputtering deposition, subsequently by post-annealing treatment in forming gas.

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