Pan Ling, Lew Kok-Keong, Redwing Joan M, Dickey Elizabeth C
Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Nano Lett. 2005 Jun;5(6):1081-5. doi: 10.1021/nl050605z.
There have been extensive studies of germanium (Ge) grown on planar silicon (Si) substrates by the Stranski-Krastanow (S-K) mechanism. In this study, we present S-K growth of Ge on Si nanowires. The Si nanowires were grown at 500 degrees C by a vapor-liquid-solid (VLS) method, using silane (SiH4) as the gaseous precursor. By switching the gas source from SiH4 to germane (GeH4) during the growth and maintaining the growth conditions, epitaxial Ge islands deposited on the outer surface of the initially formed Si nanowires. Transmission electron microscopy (TEM), scanning TEM, and energy-dispersive X-ray spectroscopy techniques were utilized to identify the thin wetting layer and the three-dimensional Ge islands formed around the Si core nanowires. Cross-sectional TEM verified the surface faceting of the Si core nanowires as well as the Ge islands.
已经有大量关于通过斯特兰斯基-克拉斯坦诺夫（S-K）机制在平面硅（Si）衬底上生长锗（Ge）的研究。在本研究中，我们展示了在硅纳米线上生长锗的S-K生长过程。硅纳米线在500摄氏度下通过气-液-固（VLS）方法生长，使用硅烷（SiH4）作为气态前驱体。在生长过程中通过将气体源从SiH4切换为锗烷（GeH4）并保持生长条件，外延锗岛沉积在最初形成的硅纳米线的外表面上。利用透射电子显微镜（TEM）、扫描TEM和能量色散X射线光谱技术来识别围绕硅芯纳米线形成的薄润湿层和三维锗岛。横截面TEM验证了硅芯纳米线以及锗岛的表面刻面。
