“FABRICATION AND CHARACTERIZATION OF SILICON NANOWIRES” A thesis Submitted in partial fulfilment of the requirement For the degree of Master of Science in physics

In this project work Si nanowires were fabricated on the Si substrate by aqueous method. In this aquoues method Ag is used for electroless chemical etching. The precursors those were taken are AgNO3, HF and H2O2. Si nanowires are fabricated at 550C. The samples were characterized by X-ray diffraction and scanning electron microscope. Result shows morphology of the Si nanowires by scanning electron microscope. X-ray diffraction confirms the phase Si.The XRD analysis confirms the phase of silicon and crystalline nature of silicon .It is found to be single crystalline with plane (1 0 0).The SEM study shows that the particles were uniform and afterwards the non uniformity arises. At 60 second of electroless deposition, the particles shape became anisotropic. Some of the particles have grown vertically. This kind of non uniform pattern can cause a nonuniform distribution of Silicon nanowires. It is confirmed that the morphology of the nanowires also depends on the resistivity of the wafers.The magnified HRTEM image shows the well-resolved lattice spacing of the silicon nanowire, which depicts the crystalline nature of the silicon nanowire.