中文摘要：

采用带有RHEED的MBE技术,利用RHEED图像演变实时监控薄膜生长状况,通过RHEED强度振荡测算薄膜生长速率,在GaAs（001）基片上同质外延GaAs薄膜。利用STM对MBE生长的GaAs薄膜表面的熟化过程进行了深入研究。研究发现,随着退火时间的延长,刚完成生长的GaAs表面从具有大量岛和坑的粗糙表面逐渐熟化,在熟化过程中岛不断合并扩大并与平台结合,而坑却逐渐消失。指出当熟化过程完成后GaAs表面将进入原子级平坦状态,并详细解释了熟化过程GaAs表面各种形貌特征形成的内在原因。

英文摘要：

GaAs films were prepared on GaAs （001） substrate by MBE, and the Ostwald ripening process of the GaAs surface were studied though STM in this paper. During the growth, RHEED intensity oscillations and RHEED patterns were used to measure and monitor the real-time growth rate and status. After growth and subsequent annealing, GaAs films were quenched down to room temperature and transferred into STM chamber under ultra high vacuum for scanning. STM images showed that GaAs surface should ripen gradually starting from the as-grown surface if one prolongs its annealing time. During the ripening process of GaAs films, all kinds of islands will coalesce and merge into terraces finally, at the same time the pits will dissolve in terraces. We explained the reasons for various morphology revolutions on GaAs surface during the ripening process. Af- ter ripening, the GaAs surface reached ordered flat morphology.