Effects of rapid thermal annealing on crystallinity and Sn surface segregation of Ge_(1-x)Sn_x films on Si(100) and Si(111) |
| |
| Affiliation: | Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, East Main Building, School of Microelectronics, Xidian University, Xi'an 710071, China |
| |
| Abstract: | Germanium-tin films with rather high Sn content (28.04% and 29.61%) are deposited directly on Si (100) and Si (111) substrates by magnetron sputtering. The mechanism of the effect of rapid thermal annealing on the Sn surface segregation of Ge1-xSnx films is investigated by x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The x-ray diffraction (XRD) is also performed to determine the crystallinities of the Ge1-xSnx films. The experimental results indicate that root mean square (RMS) values of the annealed samples are comparatively small and have no noticeable changes for the as-grown sample when annealing temperature is below 400℃. The diameter of the Sn three-dimensional (3D) island becomes larger than that of an as-grown sample when the annealing temperature is 700℃. In addition, the Sn surface composition decreases when annealing temperature ranges from 400℃ to 700℃. However, Sn bulk compositions in samples A and B are kept almost unchanged when the annealing temperature is below 600℃. The present investigation demonstrates that the crystallinity of Ge1-xSnx/Si (111) has no obvious advantage over that of Ge1-xSnx/Si (100) and the selection of Si (111) substrate is an effective method to improve the surface morphologies of Ge1-xSnx films. We also find that more severe Sn surface segregation occurs in the Ge1-xSnx/Si (111) sample during annealing than in the Ge1-xSnx/Si (100) sample. |
| |
| Keywords: | Ge1-xSnx films crystallinity Sn surface segregation Sn surface composition |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《中国物理 B》浏览原始摘要信息 |
|
点击此处可从《中国物理 B》下载免费的PDF全文 |
|
