Determination of lattice distortion in (GaAs)28(AlAs)24 superlattice layers by X-ray diffraction

• Published in: Japanese Journal of Applied Physics Vol. 25; no. 12; pp. 1834 - 1841
• Main Authors: KASHIHARA, Y, KASE, T, HARADA, J
• Format: Journal Article
• Language: English
• Published: Tokyo Japanese journal of applied physics 01-12-1986
• Subjects: Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Crystal growth; Gallium Arsenides; Aluminium Arsenides; Lattice distortion; Molecular beam condensation; Epitaxy; Experimental study; X ray diffraction; Superlattice; Inorganic compound; Thin film
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/jjap.25.1834

The structure of a (GaAs)
28
(AlAs)
24
superlattice grown by MBE has been characterized in detail by X-ray diffraction. By applying a new method of Fourier analysis (Harada
et al
.: Jpn. J. Appl. Phys. 24 (1985) L62), both the concentration and lattice distortion modulations existing in the multilayer were determined on the basis of the integrated intensities of the satellite reflections around the (400) fundamental Bragg reflection. Both modulations were found to be like a step function. It is pointed out that the width of the boundary between the two regions should be narrow and less than two intermolecular layers. The spacings between successive cation layers were 2.827 and 2.835 Å in the regions of GaAs and AlAl, respectively, along the (001) direction. This is in good agreement with the values calculated from the Poisson expansion model.