Effect of lattice mismatch in ZnSe epilayers grown on GaAs by molecular beam epitaxy

Abstract

We report a detailed study of the effect of lattice mismatch on ZnSe epilayers grown on 〈001〉 GaAs by molecular beam epitaxy using photoluminescence (PL), x-ray diffraction, and transmission electron microscopy (TEM) techniques. We find that our samples are of high quality, exhibiting sharp and strong bound excitons, and that these bound excitons shift to higher energies due to tetragonal distortion as the thickness of the ZnSe epilayer is systematically reduced from ∼1 to 0.1 μm. Fairly good agreement is found between PL and x-ray data for the total strain relaxation as a function of layer thickness. TEM measurements are also used to estimate an inelastic component of the strain relaxation in the layers.

Internal magnetic field in thin ZnSe epilayers

“…By assuming that the PL peak occurs at the direct band gap energy, we can use the shift in the PL to estimate the in-plane strain in the samples. 12 To first order, these calculations predict compressive strain in the range from 1 ϫ 10 −3 to 3 ϫ 10 −3 , which is comparable to the values quoted in existing measurements of samples of similar thicknesses. 9 XRD measurements ͓Figs.…”

Investigation of the Strains at ZnSe/GaAs Interfaces by Raman Scattering

“…3. Similar results obtained from photoluminescence (PL), X-ray diffraction (XRD), and transmission electron microscopy (TEM) are also included for comparison [36].…”

Effect of microstructure on the nanomechanical properties of Zn1−xCdxSe alloys

“…Consequently, for Zn 1Àx Cd x Se epilayers, partial strain relaxation occurs when the thickness is ca. 0.1-0.2 mm [27,28]. This relaxation generates misfit dislocations and degrades the crystal.…”