摘要
为了应用平板式射频磁控溅射设备制备出良好介电性能的钛酸锶钡(BST)纳米薄膜,研究了溅射过程中不同氧分压(pO2)对沉积薄膜的化学成分、结晶性、表面形貌、电学性能的影响.实验结果表明:纯氩无氧气氛沉积的BST纳米薄膜化学成分符合化学计量比,经750℃、30 min氧气保护热处理后,呈现出BST材料固有的钙钛矿相,有较高的介电常数(rε=700)和较低的漏电流密度(1.9μA/cm2);氧氩混合气氛沉积的BST纳米薄膜,由于氧负离子反溅射作用,使薄膜的化学成分偏离化学计量比,经相同热处理后,不能形成相应的晶体结构,导致薄膜的rε下降、漏电流密度提高,介电性能变坏;pO2的变化对沉积薄膜的化学成分影响不大.
(Ba, Sr) TiO3(BST) thin films of excellent dielectric properties were deposited by on-axis RF magnetron sputtering. The effect of different oxygen partial pressure on the composition, crystallization, micro-appearance and electrical properties of BST thin film was investigated. It is indicated that BST thin film prepared in pure argon gas has a stoichiometric composition. Perovskite phase can be observed after the film is annealed in oxygen ambient at 750℃ for 30 min, meanwhile high dielectric constant (εr=700) and low leakage current density (1.9 μA /cm^2) are got. BST thin film sputtered in Ar/O2 mix gas has a nonstoichiometric composition because of oxygen negative ions bombardment of the growing film, and it can not form perovskite phase absolutely, thus leading to the decrease of the dielectric constant as well as the increase of the leakage current density of BST thin film. The various oxygen partial pressures do not strongly affect the composition of BST thin film.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2006年第1期108-111,共4页
Journal of Shanghai Jiaotong University
基金
上海市科委纳米专项项目(0214nm032)
教育部科学技术研究重大项目资助(0307)
关键词
钛酸锶钡
射频磁控溅射
氧分压
X射线衍射
介电性能
(Ba, Sr) TiO3 (BST)
RF magnetron sputtering
O2 partial pressure
X-ray diffraction
dielectrical properties