La_(0.9)Ba_(0.1)MnO_(3-δ)薄膜的结构及物性研究

Study on Structure and Properties of La_(0.9)Ba_(0.1)MnO_(3-δ) Film

通过射频磁控溅射法在Si（100）基片上沉积了La0.9Ba0.1MnO3-δ（LBMO）薄膜，并得到在不同温度下退火后的薄膜。采用X射线衍射（XRD），扫描隧道显微镜（STM），X射线光电子能谱（XPS），四探针法等手段对退火后薄膜的结构、微结构、表面化学态、磁电阻等性质进行了系统研究，结果表明，薄膜在800～850℃温度范围内退火，形成单相结构且晶粒与基片之间存在着相对固定的外延关系。退火温度不同会引起薄膜中含氧量的不同。在温度为300K，磁场为1．5T的条件下，退火温度为850℃的薄膜样品磁电阻可高达30％。

A series of thin film which were deposited on Si（100） single crystal substrate by the RF magnetron sputtering were annealing at different temperature. X-ray diffraction （XRD）, scanning tunnlling microscope （STM）, X-ray photoelectron spectroscopy （XPS） , and four prob method were respectively used to measure the phase structures, the morphologies, surface state and magnetore- sistance. The study results show the grains of LBMO films annealed in range of 800 - 850℃ have an epitaxial relationship with Si （100） substrate. The measuring results show that different annealing temperature lead to the quantity of oxygen changing in thin film. Magnetoresistance of the thin film which are annealed at 850℃ arrive at about 30 % when the temperatue reach 300K and the magnetic field reach 1.5T.