Indium antimonide-bismuth compositions grown by molecular beam epitaxy

Abstract

Thin films of InSb-InBi solid solutions have been prepared by molecular beam epitaxy. Using in situ reflection electron diffraction, conditions for epitaxial growth of stoichiometric layers were established on (001) and (110) surfaces of both InSb and GaAs wafers. Bi is shown to modify the diffraction patterns of (001) InSb from C(8×2) and (√2×√2) 45° to (1×3). Surface residence times of Bi were found indefinitely long (≳10 min) at temperatures ?420 °C. Bi incorporation into InSb during growth by molecular beam epitaxy is strongly dependent on Bi surface concentration, and influenced by substrate temperature and surface nonstoichiometry. Secondary ion mass spectrometry depth profiling and 2.5 MeV ion dechanneling spectra showed that ∼3% Bi can be incorporated substitutionally in Sb sites, under In rich growth conditions (largest available concentration of VSb sites). Increased Bi surface accumulation and interstitial incorporation are observed under Sb-rich surface conditions and as the relative flux of Bi is increased. Excess surface Bi forms liquid alloys with excess In during growth above 280 °C which alters the incorporation. These alloys solidify on the surface of grown films on cooling. Absorption cut-off wavelengths are unaffected by interstitial Bi concentrations; however, cutoffs out to ≳9.5 μm at 77 K are observed for Bi-doped films grown under In-rich conditions.

Growth of InxGa1−xAs/GaAs heterostructures using Bi as a surfactant

“…Bismuth has been shown to modify the diffraction pattern of ͑001͒ InSb from C (8ϫ2) to 1ϫ3 in an earlier study. 16 An activation energy for Bi desorption of ϳ1.3 eV was obtained from the slope of the transitions. This is less than the activation energy for Bi evaporation from bulk Bi, 1.8 eV.…”

Structural properties of bismuth-bearing semiconductor alloys

“…We found reports of the growth of only one bismuth-bearing zincblende alloy in the literature (Jean-Louis and Hamon, 1969a,b;Joukoff and Jean-Louis, 1972; Oe et al, 1981;Noreika et al, 1982Noreika et al, , 1983. Using equilibrium growth methods, InSbl,Bi, alloys were grown with up to -2.6 mole percent bismuth, the solid-solubility limit of InBi in InSb.…”

Anomalous photoluminescence in InP1−xBix

“…A low growth temperature is undesirable as it typically leads to increase of defect densities and optical quality degradation. Besides, accurate control of Bi flux to avoid forming Bi droplets and use of a low growth temperature to incorporate a significant fraction of Bi are required during epitaxial growth789101112. Thus, there are many challenges for growing high-quality bismide alloy.…”