Refining And Thin Films Deposition Of Indium Iodide (InI) Polycrystal

With the increasing depletion of fossil energy, the three technologies, wind energy,nuclear energy and photovoltaic power, are known as the solution to global energy shortage and environmental pollution. Semiconductor materials used for nuclear radiation detectors have a very widely prospect. The research field of room-temperature nuclear radiation detection focuses attention on indium iodide(In I) crystal, due to its large band gap, resistivity and carrier mobility-life time product, high detection efficiency, energy resolution and other excellent properties.Considering the attractive prospect of indium iodide crystal, this paper firstly discussed the purification process of high purity and nearly theoretical stoichiometric ratio indium iodide polycrystal, and analyzed the purification effect from component, structure and impurity concentration; Secondly discussed the preparation of indium iodide polycrystalline thin film, and analyzed the feasibility of indium iodide polycrystalline thin films’ application to nuclear radiation detector from its structure and optical properties based on the theory of crystal defects and thin film growth.First, the band structure and crystal structure of indium iodide crystal, the contributing factor and effects of several defects at the process of crystal growth, and all stages of thin film growth were described, providing theoretical basis for the experiment.Secondly, the process rate, temperature and other parameters were obtained through analyzing the properties of indium iodide and the principle of zone refining process. The indium iodide polycrystal was purified using the horizontal zone refining method, the lattice structure, morphology, component and impurities concentrations were investigated by X-Ray Diffraction(XRD), Scanning Electron Microscope Energy Dispersive Spectrometer(SEM-EDS) and Inductively Coupled Plasma Atomic Emission Spectrometry(ICP-AES).Finally, indium iodide polycrystalline thin films were deposited on glass substrates by vacuum evaporation technique. Ultraviolet spectrophotometry and other instruments were employed to analyze the structure, surface morphology and UV-Vis spectra of theindium iodide polycrystalline thin films.