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利用高分辨电子显微术，对在ＧａＰ基体上由分子束外延生长六角ＧａＮ晶体薄膜中的晶体缺陷结构进行了研究．实验中发现了ＧａＮ薄膜外延生长过程中产生的一种典型早期刃型位错结构．此晶体缺陷位于一大块ＧａＮ晶粒内部，其外观类似于一段（１１２０）晶界．它由一条（１１２０）高能孤立晶界段及其两端的两个１／６［１１２０］不完全刃型位错组成．从大晶格失配材料之间分子束外延生长的机理上对这种缺陷结构的形成进行了解释．
The structure of crystal defects in hexagonal GaN crystal films grown by molecular beam epitaxy on GaP substrates was investigated by high resolution electron microscopy. In the experiment, a typical early edge dislocation structure was found during the epitaxial growth of GaN films. This crystal defect is located inside a large GaN grain and looks similar to a section of (1120) grain boundaries. It consists of a (1120) high energy isolated grain boundary segment and two 1/6 [1120] incomplete edge dislocations at both ends. The formation of this defect structure is explained by the mechanism of molecular beam epitaxy between large lattice mismatch materials.