Author(s): Liu, XQ (Liu, Xiangquan); Zheng, J (Zheng, Jun); Li, MM (Li, Mingming); Wan, FS (Wan, Fengshuo); Niu, CQ (Niu, Chaoqun); Liu, Z (Liu, Zhi); Zuo, YH (Zuo, Yuhua); Xue, CL (Xue, Chunlai); Cheng, BW (Cheng, Buwen)

Source: JOURNAL OF PHYSICS D-APPLIED PHYSICS Volume: 54 Issue: 43 Article Number: 435101 DOI: 10.1088/1361-6463/ac17b4 Published: OCT 28 2021

Abstract: Relaxed GeSn films with a high Sn content (>13%) were grown on Ge (100) substrates via magnetron sputtering epitaxy through a component-grade GeSn buffer layer structure. Raman spectroscopy, high-resolution x-ray diffraction, and cross-sectional transmission electron microscopy revealed that Ge0.861Sn0.139 alloys, with a degree of strain relaxation of up to 96.1%, can be achieved through a component-grade buffer layer structure. The threading dislocation density was estimated to be around 2x10(8) cm(-2). The atomic surface flatness of the GeSn alloys was confirmed by atomic force microscopy, and the surface roughness was observed to be below 1 nm. Moreover, the thermal stability of GeSn samples was investigated. The results indicated that the component-grade structure is effective for realizing a high Sn composition and high relaxation of the GeSn alloy.

Accession Number: WOS:000682143300001

ISSN: 0022-3727

eISSN: 1361-6463

Full Text: https://iopscience.iop.org/article/10.1088/1361-6463/ac17b4