Transfer of 200 mm GeSn wafers using bonded etch-back silicon-on-insulator process

This is the authors' abstract. We don't add key points for this paper.

GeSn alloys exhibit significant potential for mid-infrared devices. The increase of Sn content and the application of tensile strain can convert such alloys into direct bandgap semiconductors. However, a virtual Ge buffer substrate and a grading of the tin concentration are generally required for the growth of high tin content GeSn layers. This growth approach leads to misfit dislocations in the vicinity of the optically active GeSn layer on top and to a degraded optical confinement. In this work, we demonstrate a CMOS-compatible transfer of 200 mm GeSn wafers with a 14–16 % tin content. A comparative study between germane and digermane precursor gases for GeSn growth is also conducted. The crystallinity and composition of as-grown and transferred GeSn layers are characterized using x-rays, Raman and photoluminescence spectroscopies, Atomic Force Microscopy and Transmission Electron Microscopy.