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以GaN为代表的Ⅲ族氮化物在微电子、光电子和传感器等领域均发挥了重要作用。但是由于大尺寸的单晶GaN衬底仍无法实现,目前绝大多数氮化物材料都是通过异质外延的方式来实现,外延材料和异质衬底之间巨大的晶格失配和热失配是导致GaN外延层中位错密度较高的主要原因。侧向生长(ELOG)技术是GaN异质外延中降低位错密度的一种有效方法,总结了该项技术的特点,并对单步ELOG技术、双步ELOG技术、悬空ELOG技术以及无掩膜ELOG技术等多种技术趋势进行了总结。ELOG技术可以有效降低位错密度,但是仍需降低工艺复杂性和减少沾污。
Group III nitrides represented by GaN have played an important role in the fields of microelectronics, optoelectronics and sensors. However, due to the large size of single crystal GaN substrate can not be achieved, the vast majority of nitride materials are achieved by heteroepitaxy way, the huge lattice mismatch and thermal loss between the epitaxial material and the heterogeneous substrate The main reason that the dislocation density in the GaN epitaxial layer is higher is the main reason. Lateral growth (ELOG) technique is an effective method to reduce dislocation density in heteroepitaxy of GaN. It summarizes the characteristics of this technique. The single-step ELOG technique, double-step ELOG technique, vacant ELOG technique, ELOG technology and other technology trends were summarized. ELOG technology can effectively reduce the dislocation density, but still need to reduce process complexity and reduce contamination.