TY - JOUR AU - Zaumseil, P. AU - Hou, Y. AU - Schubert, M. A. AU - von den Driesch, N. AU - Stange, D. AU - Rainko, D. AU - Virgilio, M. AU - Buca, D. AU - Capellini, G. TI - The thermal stability of epitaxial GeSn layers JO - APL materials VL - 6 IS - 7 SN - 2166-532X CY - Melville, NY PB - AIP Publ. M1 - FZJ-2018-04797 SP - 076108 PY - 2018 AB - We report on the direct observation of lattice relaxation and Sn segregation of GeSn/Ge/Si heterostructures under annealing. We investigated strained and partially relaxed epi-layers with Sn content in the 5 at. %-12 at. % range. In relaxed samples, we observe a further strain relaxation followed by a sudden Sn segregation, resulting in the separation of a β-Sn phase. In pseudomorphic samples, a slower segregation process progressively leads to the accumulation of Sn at the surface only. The different behaviors are explained by the role of dislocations in the Sn diffusion process. The positive impact of annealing on optical emission is also discussed. LB - PUB:(DE-HGF)16 UR - <Go to ISI:>//WOS:000440603600010 DO - DOI:10.1063/1.5036728 UR - https://juser.fz-juelich.de/record/851089 ER -