Open AccessStructural transformation of Sb‐based high‐speed phase‐change material
Author(s) -
Matsunaga Toshiyuki,
Kojima Rie,
Yamada Noboru,
Kubota Yoshiki,
Kifune Kouichi
Publication year - 2012
Publication title -
acta crystallographica section b
Language(s) - English
Resource type - Journals
eISSN - 1600-5740
pISSN - 0108-7681
DOI - 10.1107/s0108768112039961
Subject(s) - materials science , crystal structure , phase (matter) , crystallography , amorphous solid , lattice (music) , analytical chemistry (journal) , phase change material , crystal (programming language) , thermal , chemistry , thermodynamics , physics , organic chemistry , chromatography , computer science , acoustics , programming language
The crystal structure of a phase‐change recording material (the compound Ag 3.4 In 3.7 Sb 76.4 Te 16.5 ) enclosed in a vacuum capillary tube was investigated at various temperatures in a heating process using a large Debye–Scherrer camera installed in BL02B2 at SPring‐8. The amorphous phase of this material turns into a crystalline phase at around 416 K; this crystalline phase has an A7‐type structure with atoms of Ag, In, Sb or Te randomly occupying the 6 c site in the space group. This structure was maintained up to around 545 K as a single phase, although thermal expansion of the crystal lattice was observed. However, above this temperature, phase separation into AgInTe 2 and Sb–Te transpired. The first fragment, AgInTe 2 , reliably maintained its crystal structure up to the melting temperature. On the other hand, the atomic configuration of the Sb–Te gradually varied with increasing temperature. This gradual structural transformation can be described as a continuous growth of the modulation period γ.