Premium
Local Structure Analysis of Ga 1—x In x N Alloy Using Extended X‐Ray Absorption Fine Structure Measurements
Author(s) -
Miyajima T.,
Kudo Y.,
Liu K.Y.,
Uruga T.,
Asatsuma T.,
Hino T.,
Kobayashi T.
Publication year - 2001
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/1521-3951(200111)228:1<45::aid-pssb45>3.0.co;2-#
Subject(s) - wurtzite crystal structure , extended x ray absorption fine structure , coordination number , bond length , alloy , crystallography , materials science , absorption (acoustics) , interatomic potential , molecular physics , atomic physics , analytical chemistry (journal) , crystal structure , absorption spectroscopy , chemistry , molecular dynamics , computational chemistry , physics , optics , ion , metallurgy , chromatography , composite material , organic chemistry , hexagonal crystal system
We investigated the local atomic structure around In atoms of MOCVD‐grown Ga 1— x In x N alloy (0.01 ≤ x ≤ 0.21) using extended X‐ray absorption fine structure (EXAFS) measurements of the In K‐edge. For x ≤ 0.16, the In–Ga and In–In atomic distances were constant at 3.22–3.30 Å and 3.25–3.30 Å, respectively, and close to the Ga–Ga atomic distance in the ideal wurtzite GaN. On the other hand, the In–N bond length was constant at 1.85–2.21 Å, which is close to that in the ideal wurtzite InN. These results suggest that the internal strain of the Ga 1— x In x N alloy is relaxed by the bond angle changing of In–N–Ga or In–N–In. The coordination numbers of the second‐nearest neighbor In of In were higher than that estimated from random GaInN alloy, in which In atoms randomly occupy the cation sublattice of GaInN alloy. This behavior can be explained by the segregation of In atoms starting even at x = 0.01. For x = 0.21, the interatomic distance and the coordination number could not be accurately estimated using our simple model, in which single interatomic distances of In–Ga and In–In were assumed.