Formation of atomically flat GaAs(110) surfaces and step-edge dynamics of surface adatoms

在这项工作中，我研究了生长中断退火在GaAs（110）上形成原子级平坦表面的机制。我在GaAs（001）晶片的解理（110）边缘上通过分子束外延生长的外延表面上进行生长中断退火。退火后，原子级平坦的表面伴随着特征形状的单原子层台阶边缘，这取决于所引入的外延层的厚度分布的结晶方向，形成。结果表明，GaAs（110）表面原子迁移势的晶体学各向异性对退火过程中平坦表面的形成有很大影响。此外，我还发展了一种波导透射光谱方法，用于定量表征GaAs（110）表面的光学性质（发射、吸收等）。用生长中断退火技术制备了具有原子级平坦异质界面的GaAs（110）量子威尔斯阱。

In this work, I investigated formation mechanisms of atomically flat surfaces on GaAs(110) by growth-interruption annealing. I performed growth-interrupt anneal on the epitaxial surfaces grown, by molecular-beam epitaxy, on the cleaved (110) edges of GaAs(001) wafers. After annealing, atomically flat surfaces accompanied with characteristic-shaped monatomic-layer step edges, which depend on the crystallographic direction of the introduced thickness distribution of the epitaxial layers, were formed. The results imply that the flat-surface formation during annealing is largely influenced by crystallographic anisotropy of migration potential of adatoms on GaAs(110).In addition, I developed a waveguide-transmission spectroscopy method to be used for quantitative characterization of optical properties (emission, absorption, etc.) of the GaAs(110) quantum wells with atomically-flat hetero-interfaces formed by the growth-interrupt annealing technique, has been developed.