Study On The Electronic Structure And Physical Properties Of III-V Compounds

III-V compounds span a large band gap, The band gap of InN as small as0.7eV, andthe band gap of AlN as high as6.28eV. InP and AlN as the representative of III-Vsemiconductors due to the broad application prospects in optoelectronic andmicroelectronic devices, aroused great interest of researchers. InP band gap is1.34eV,while AlN have two structures (wurtzite, sphalerite) band gap widths up to6.20and5.11eV respectively. This article focuses on considering wurtzite AlN. Have the possibility ofturning the semiconductor into semi-metallic material through doping under a high Curietemperature, so spintronic device has potential applications. In our paper, we calculate InPand AlN based semiconductor, the use of the Wien2k software.And the Origin8is used todrawing.First, we construct a222InP supercell, and investigate the electronic and opticalthat compared with the intrinsic materials, the Fe doped materials show half-metallicproperty possess magnetic. Electrons transition from the valence band to conduction bandeasier with conductivity enhancement. Especially when concentration of dopant increases,the optical absorption edge shift to low energy region. Compared with Cr-doped andMn-doped, the band gap reduces which is mainly due to the strong hybridization betweenCr3d、Mn3d and O2p states among the energy level of conduction band bottom causedby the introduction of a number of impurities. With Cr-doped、Mn-doped and Fe-doped,the band gap becomes more and more small than intinsic, and the conductivity hassignificant enhancement. The imaginary part of the dielectric function and absorptionspectra occur redshift. Meanwhile, in order to better study the III-V compoundsemiconductors,we constructed AlN nano-surface model,Co-doped first performed,followdby non-metallic doping C,followd by Co-C doped to study the electronic structure andoptical properties of AlN nano surface.The results show that: the Co-doped AlNnano-elements presented semi-metallic surfaces. there exists strong hybridization betweenCo4s and Al3d, and causes a series of impurity bands at Fermi level, the electricalconductivity of the material enhanced, the absorption spectra broadened,in the UV-visibleregion, the refractive and reflectance index increases. When doped C, there exist spin up occupied states at Fermi level, metal enhanced.In terms of optical properties, the C atom ofAlN doped optical properties has increased overall, the direction of movement occurs to alower energy, the overall values are higher than in the ultraviolet region of theeigenstates.When Co-C doped,AlN presented semi-metallic surfaces,conductivityenhancement.Optical properties has been greatly improved than eigenstates, especially hasmore clearly visible range in the visible region.The intrinsic optical properties of AlN inthe visible region is weak, the absorption coefficient of the doping after the doped systems,the light absorption coefficient,reflectance and refractive index than the intrinsic AlN has ahigh intrinsic upgrade.