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5-inch diameter Bi 3.15 Nd 0.85 Ti 3 O 12 (BNT) ferroelectric thin films were prepared on Si wafers by a modified pulsed laser deposition method, in which two laser scanning rates and 6-inch diameter target were used. The investigation on the distribution of the film thickness reveals that the laser scanning technique used in conjunction with the large-diameter target can improve the uniformity of film thickness. Especially the reasonable setup of the laser scanning rate ablating the fringe area of the large target has a prominent effect on weakening the edge deviation of thickness distribution. Such phenomenon was fundamentally explained by the simulation results on the ablation tracks of the laser beam on target. Through optimizing the laser scanning rates, BNT thin film with uniform thickness was obtained on 5-inch diameter Si wafer and the maximum variation in film thickness was found to be less than ± 2.5%. The results of X-ray photoelectron spectroscopy and X-ray diffraction show that the prepared 5-inch BNT thin film has great uniformity in stoichiometry and crystallinity. In addition, the measurements of electrical properties indicated that the prepared BNT thin film exhibits good ferroelectric property and I – V characteristic.

The Melut Basin is a rift basin elongated in NW-SE direction located in south Sudan. Under the influence of Intracratonic extensional forces that resulted from the opening of the Atlantic, and associated left-lateral strike-slip, a series of synsedimentary structures are developed in Melut Basin. On the basis of different features of structure development continuous, late deformation and drive mechanism, there are mainly three types of synsedimentary structures developed, i.e. inherited structures, fault-related structures and differential compaction-related structures, respectively. Inherited structures are inherited from paleo-uplift and reformed by later-stage faulting. Fault-related structures form as a result of displacement decreases with distance from the fault surface caused by low dip angle listric fault. The origins for the listric fault include listric basin-bounding fault caused by adjacent titled block and strike-slip fault involved into shale formation. The main two types of differential compaction-related structures are caused by intense differential compaction within intervals of sandy conglomerate of alluvial fan and the original sediments are inclined to collapse into depression during sedimentary compaction, respectively. The synsedimentary fault and its assemble pattern controlled the distribution of sedimentary facies, the synsedimentary structures has great influence for the generation, migration, accumulation and preservation of oil and gas.