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利用选区电子衍射及明暗场电子衍射成像技术，在Ｍｎ＋注入ＧａＡｓ及随后退火的样品表层发现有二十面体准晶颗粒形成．能谱及电子能量损失谱分析表明，这些粒子不含Ａｓ，由Ｇａ和Ｍｎ元素组成，约含５０ａｔ％的Ｍｎ；其结构具有五次对称性和非周期分布的电子衍射斑点．这些具有２／ｍ３５对称性的ＧａＭｎ准晶粒子同具有闪锌矿结构的ＧａＡｓ基体之间具有确定的取向关系：ｉ－５∥〔１１０〕ＧａＡｓ；ｉ－３∥〔１１１〕ＧａＡｓ；ｉ－２∥〔１２１〕ＧａＡｓ．用磁力显微镜分析发现这些粒子中的许多粒子具有铁磁性．首次在半导体材料中发现有准晶
Using the selected area electron diffraction and light and dark field electron diffraction imaging techniques, icosahedral quasicrystalline particles were found on the surface of Mn + implanted GaAs and subsequent annealed samples. Spectra and electron energy loss spectroscopy analysis showed that these particles contain no As and consist of Ga and Mn with about 50at% Mn. The structure has five symmetry and non-periodic electron diffraction spots. These GaMn quasicrystals with a 2 / m35 symmetry have a defined orientation relationship with a GaAs matrix having a zinc blende structure: i-5 // [110] GaAs; i-3 // [111] GaAs; ∥ [121] GaAs. Magnetic particle analysis revealed many of these particles were ferromagnetic. For the first time in quasi-crystalline semiconductor materials found