Fabrication Of And Research On (Bi, La)₄Ti₃O₁2 Ferroelectric Nanofiber And Nano-field Effect Transistor

Over the last decade, rapid progress in the field of nanoscience has been increasingly attracting the attention of the scientific team as well as society at large on the corresponding technological applications, which are the object of so called nanotechnology. In advanced materials, integrated electronic circuits, biomedical, chemical catalysis, nanotechnology is gradually showing more and more influence.As no environmental pollution, the larger spontaneous polarization, good retention and fatigue resistance of bismuch layer-structured ferroelectric (BLSF) material contrast to the traditional lead-based ferroelectric materials, the BLSF materials have been gradually taken their place. The research on ferroelectric materials were mainly concentrated in the area of bulk and thin films, but little work has been done in nanoscale. So we have started a ferroelectric materials research on nanoscale in this paper.In the first chapter of this paper, the concept and classification of nanotechnology were presented as well as the preparation method of nano-materials, and at the end of this chapter the basis of this selected topics were explained. In the second chapter, the principle of electrospinning method was introduced as well as the experimental equipment and process. The configuration process of electrospinning solution of factors and considerations were also discussed in detail. Finally we draw the conclusion: electrospinning solution concentration, viscosity consistency, electrical conductivity, electrospinning voltage and curing distances have a significant impact on the quality of spinning nanofibers.In chapter three, the morphology, crystallized phase, crystal structure and ferroelectricity were investigated by means of scanning electronmicroscopy, X-ray diffraction analysis ,high resolution transmission electron microscopy and piezoelectric force microscopy respectively. At last, nanofibers with fine crystallinity were observed with fiber diameters in the range of 100-300 nm and length over 150μm after baking 1h at 280 oC and annealing at 700 oC for another hour. The ferroelectricity of the nanofibers has been confirmed by the displacement-voltage (D-V) butterfly loop obtained from PFM measurements; a piezoelectric hysteresis loop (d33-V) has also been calculated from the D-V curve. From the d33-V loop, a three-times higher effective piezoelectric coefficient (d33) compared with that of thin film materials could be obtained, which shows the advantage of one-dimensional ferroelectric material. These characteristics suggest that ferroelectric nanofibers may be well suited for the realization of nanoscale nonvolatile memory devices.In chapter four, we change the research object from materials to electric device. At first, the typical fabrication process of nano device were described as well as some equipments and instruments. And then, ZnO thin film field effect transistor and ZnO nanorob field effect transistor had been fabricated with vacuum deposition apparatus. The Keithley4200 Semiconductor Tester were used to test the transfer and output characteristics. Although the test results are generally, our preparation method is unique and it paves the way for future research.