Microchannel epitaxy (MCE) is an outstanding technique for dislocation reduction during heteroepitaxial growth when there is a large lattice mismatch. This paper describes the MCE mechanism in detail together with experimental results. Directional growth is a principal concern of MCE, and is enabled through the assessment and control of the elementary processes of crystal growth. Vertical microchannel epitaxy (V-MCE) involves perpendicular growth relative to a substrate, from microchannels established as openings in a mask, while horizontal microchannel epitaxy (H-MCE) is growth parallel to the substrate surface. Even if many dislocations are present in the microchannels, directional growth vastly reduces their number in the grown crystal. MCE is beneficial for the fabrication of devices, as well as the quantitative study of the fundamental processes involved in crystal growth. This paper quantitatively discusses the growth mechanism involved in H-MCE of GaAs in the thickness direction. Fitting the forms of spiral steps observed on flat surfaces at an atomic level enables the accurate derivation of surface supersaturation at the time of growth. Moreover, since a simple mechanism for controlling growth in the vertical direction can be established for H-MCE with a single step source, quantitative discussion of crystal-growth mechanisms is now possible.

当存在较大的晶格失配时，微通道外延（MCE）是减少异质外延生长过程中位错的一项出色技术。本文详细介绍了MCE机制以及实验结果。定向生长是MCE的主要关注点，并且可以通过评估和控制晶体生长的基本过程来实现。垂直微通道外延（V-MCE）涉及相对于基板的垂直生长，该垂直生长是通过在掩模中形成开口的微通道实现的，而水平微通道外延（H-MCE）则平行于基板表面生长。即使微通道中存在许多位错，定向生长也会大大减少其在晶体生长中的数量。MCE对于设备的制造是有益的，以及对晶体生长所涉及的基本过程的定量研究。本文定量讨论了GaAs H-MCE在厚度方向上的生长机理。在原子水平上拟合在平面上观察到的螺旋台阶形式，可以在生长时精确推导表面过饱和度。而且，由于可以通过单个步骤的源为H-MCE建立用于控制垂直方向上生长的简单机制，因此现在可以对晶体生长机制进行定量讨论。在原子水平上拟合在平面上观察到的螺旋台阶形式，可以在生长时精确推导表面过饱和度。而且，由于可以通过单个步骤的源为H-MCE建立用于控制垂直方向上生长的简单机制，因此现在可以对晶体生长机制进行定量讨论。在原子水平上拟合在平面上观察到的螺旋台阶形式，可以在生长时精确推导表面过饱和度。而且，由于可以通过单个步骤的源为H-MCE建立用于控制垂直方向上生长的简单机制，因此现在可以对晶体生长机制进行定量讨论。