Abstract
A method to grow high quality GeSn alloy strips with assistance of Sn has been developed, and strips grow laterally on Si(111) substrates in molecular beam epitaxy (MBE) chamber. The GeSn heteroepitaxial strip has been proven to be of good crystalline quality without threading dislocations (TDs) by transmission electron microscopy (TEM). In the meantime, introduction of Sn into Ge was investigated by Raman spectra and energy-dispersive X-ray spectroscopy (EDS). In addition, size and density of GeSn strip can be adjusted by changing the growth conditions, and Sn concentration varies approximately linearly against the epitaxial temperature. Moreover, the Hall mobility of GeSn alloy strips at room temperature was 336 cm2·V-1·s-1 and the carrier concentration was 7.9×1012 cm−3 by Hall measurement. Therefore, the proposed method provides an easy technique to grow high quality GeSn materials for Si-based photonics and microelectronics applications