We proposed the low temperature formation technique of strain-relaxed Si1-x-yGexSny-on-insulator (SGTOI) structures. We found that the solid-phase reaction and the formation of single and uniform Si1-x-yGexSny layer on an insulator after annealing SiO2/Ge1-zSnz/SOI structures even at a temperature as low as 400 degrees C. We characterized the crystalline structure of SGTOI, and investigated the effects of annealing, Sn incorporation, and a SiO2 cap layer on the solid-phase reaction between Ge1-zSnz and SOI layers. The solid-phase reaction is enhanced with a higher Sn content and a thicker SiO2 cap layer, and then Si1-x-yGexSny layers are more rapidly formed. The SGTOI layer exhibits very low mosaicity and have good crystallinity. (C) 2011 Elsevier B. V. All rights reserved.