Analysis of ordering in GaInP by means of x-ray diffraction

Abstract

Ga0.51In0.49P layers grown by metal-organic vapor-phase epitaxy in the temperature range from 600 to 730 °C and with various Si-doping concentrations were studied. X-ray diffraction was used to observe the ordering in Ga0.51In0.49P layers. The rocking curves of {115} reflection have shown the existence of ordering in Ga0.51In0.49P even in Si-doped samples with an electron concentration up to 1×1019 cm−3. The samples with ordered structure exhibit an additional {1/2, 1/2, 5/2} reflection. However, no such reflection, which is related to group-III sublattice ordering, was observed in GaAs, AlGaAs, and GaInP layers grown at 730 °C. Photoluminescence (PL) and transmission electron diffraction (TED) results confirm these observations. TED patterns and especially the intensity of the additional ordering spots of Ga0.51In0.49P samples are almost unchanged in the studied doping range up to 1.7×1018 cm−3. An increase of PL peak energy attributed to the ordered structure randomization was not observed. The PL peak shift for highly doped Ga0.51In0.49P was found to be only due to the Burstein–Moss effect.

Effects of ordering and alloy phase separation on the optical emission characteristics of In1−xGaxAsyP1−y layers grown on GaAs substrates

“…The reduced FWHM values observed in the x-ray rocking curves of quaternary samples grown with low a As content suggest the existence of ordered domains with a larger lateral extension. 7 The corresponding low-temperature PL spectra of samples A, B, and C obtained at the same power density of 0.1 W/cm 2 are shown in Fig. 2.…”

“…Previous works on partially ordered InGaP and InGaAsP materials suggest spatially indirect recombination of carriers at the boundaries of domains, yielding a below band gap emission. 3,4,[7][8][9][10][11] The LE-emission peak position of the three samples exhibits a blueshift at increasing values of excitation power intensity. An example of the LE peak position ͑for example C͒ as function of power density ( P exc ) is shown in the inset of Fig.…”

X-ray diffraction study on the correlation between ordered domains size and ordering degree in InGaP/GaAs alloy layers

“…Nominally lattice-matched Inl_xGa~P/GaAs (x = 0.51) heteroepitaxial layers, grown under proper conditions, exhibir long-range order in the cationic sublattice along the (111) directions. The effect has been studied by several techniques, like transmission electron microscopy (TEM) [2], and X-ray diffraction [3]; moreover, an anomalous behaviour of the photoluminescence peak asa function of temperature has been ascribed to the presence of ordered domains [4,5].…”

Investigation of Strain Relaxation Mechanisms in InGaAs/GaAs Single Layer Films

“…Long range order can be revealed and investigated by X-ray diffraction, as it was shown for InGaP/GaAs layers [38,39]. The ordered structure in the cationic sublattice behaves as a natural GaAs/InAs superlattice on {111} planes, making allowed the 1/2 1/2 n/2 reflections, where n is an integer.…”