中文摘要：

有机半导体器件的性能在很大程度上受有机分子取向和堆积方式的影响,研究调控有机分子取向的方法对优化器件性能有重要意义.在强磁场（8.5 T）下使用有机分子束沉积方法在Si（111）衬底上制备了酞菁铁薄膜,应用X射线衍射,角分辨近边X射线吸收精细结构、偏振激光拉曼光谱,原子力显微镜等技术研究了磁场对酞菁铁薄膜的分子取向和形貌的影响.结果表明,酞菁铁分子相对于衬底呈侧立构型并形成α相的薄膜.在强磁场作用下,分子平面与衬底的夹角由63.6°增大为67.1°,形成薄膜的结晶度明显提高,晶粒更加均匀,在衬底上的分布更加有序.

英文摘要：

Molecular orientation and stacking mode are commonly considered to have vital influence on the optoelectronic performances of organic semiconductor devices via changing the dynamics of charge carriers transferring among the molecules.Highly ordered and homogeneous stacking would allow a fast band transfer mechanism in the phase domain.Therefore the controls of the molecular orientation and the stacking behavior are of great significance for optimizing the device natures.In this work,the modification and control of iron phthalocyanine（FePc） molecular orientation on Si（111） are accomplished with the aid of high steady magnetic field at room temperature.The FePc films are grown in situ by organic molecular beam deposition on the Si（111） substrates under a high magnetic field strength of 8.5 T.The Si（111） substrates are preserved at room temperature and are kept perpendicular to the magnetic field.The influences of magnetic field on the molecular orientations and the morphologies of FePc thin films are investigated by X-ray diffraction,angle dependent near edge X-ray absorption fine structure（NEXAFS）,Raman spectroscopy and atomic force microscopy（AFM）.In the presence of the external magnetic field,the deposited FePc films each show a higher crystallinity and slightly closer packing in（002） plane than those without magnetic field.The AFM images verifies more ordered and uniform morphologies of the FePc films grown in the magnetic field.NEXAFS and Raman results both reveale a standingup configuration of FePc molecules on the Si（111） substrate surface.The average tilting angle of the molecules changes from 63.6° to 67.1° when 8.5 T magnetic field is employed.The results demonstrate that the external high magnetic field distinctly enhances the orientation order of FePc molecules on Si（111） surface due to the magnetic-magnetic interactions between the magnetic field and the molecular magnetic moment.This work also demonstrates that external magnetic field is an efficient means to regu