Peculiarities of the Properties of III–V Semiconductors in a Multigrain Structure

Application of multiple correlation analysis method to modeling the physical properties of crystals (on the example of gallium arsenide)

“…In particular, it is shown in [6] that fluctuations in the concentration of background carbon and silicon impurities in undoped GaAs lead to a local change in the band gap (the formation of local density state tails) in the crystal bulk. In optical manifestations, this effect is similar to the effect of localization of states considered in [7] in the bulk and surface regions of submicron grains of a crystal. Despite the variability of the deviation of the crystal structure from stoichiometry, in both studies the calculation model is limited by the relationship of only two parameters: carrier concentrationspectral characteristic of the material.…”

“…2) The intensity of the edge band of photoluminescence (PL) with a maximum energy hn m = 1.51 eV (I FL ) is measured at 77 K by the standard method with normalization per unit (measured in rel. units) [7]. The PL is excited by a He-Ne laser with a radiation intensity of (2.5-3.0)⋅10 18 cm -2 ⋅s -1 and a focusing diameter of less than 0.5 mm.…”

“…6) The concentration of deep centers EL2 (N EL2 ) is determined by the optical absorption of light quanta with an energy of hn = 1.04 eV [7] using an MDR-2 monochromator. The excitation source is a quartz halogen compact lamp with a continuous spectrum of 60 watts.…”

“…However, the volatility of arsenic atoms during the growth of GaAs single crystals leads to a significant variability in the deviation of their structure from stoichiometry and the complexity of the stable reproduction of parameters. Studies [6,7] show that, as in any coupled multifactor system, in GaAs single crystals, a change in the concentration of one of the structural components can ambiguously affect the others. In particular, it is shown in [6] that fluctuations in the concentration of background carbon and silicon impurities in undoped GaAs lead to a local change in the band gap (the formation of local density state tails) in the crystal bulk.…”

Features of the radiative properties of quantum-size particles of narrow-gap semiconductors

“…Other excitation mechanisms are needed in this case. We used the emissioninjection mechanism in a multigrain microstructure that was discussed in detail in our earlier studies [12,13]. Subjected to the influence of the field applied to a microstructure, an excited electron is emitted from a certain QP into a nanogap and is then injected into a neighboring QP, where it undergoes a transition to the non-excited state.…”