By making use of the density functional theory (DFT) of the first principles and generalized gradient approximation method, the electronic structures and properties of ideal GaN and AlxGa1-xN crystals (x = 0.25, 0.5, 0.75) have been calculated and analyzed, and the influence of the doping quantity of x on the characteristics of AlxGa1-xN has been studied. The calculation results show that optical band gap of AlxGa1-xN crystal is widened that the Eg of AlxGa1-xN can be adjusted by the x, and the absorption spectrum shifts to high-energy direction with the increase of the x, and then the Fermi energy moves to the top of valence band slightly which leads to that conductivity weakened after mixed with the Al. At the same time, the variation trends of complex dielectric function, absorption spectrum and transitivity have been made clear, and the results show that AlxGa1-xN compounds can achieve the theoretical design of photoelectric performance. In a word, AlxGa1-xN crystals are potential semiconductors with very remarkable photoelectric properties, which can be applied in the development of the diversified GaN devices.
Cite this paper
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