Defect-free single-crystal Ge island arrays on insulator by rapid-melting-growth combined with seed-positioning technique

Single-crystal Ge island arrays on SiO₂ /Si structures are desired to merge advanced Ge devices into Si large scale integrated circuit (LSI). We have developed the rapid-melting-growth process of amorphous Ge by using Ni-imprint-induced Si (111) fine crystals (∼1 ^μmφ) as the growth seed. Arrays of (111) oriented single-crystal Ge islands with device size (∼10 mu;m φ) are uniformly fabricated on SiO₂ /Si substrates. The cross-sectional transmission electron microscopy observation reveals that Ge islands include no dislocation or stacking fault. This method opens up a possibility to achieve hybrid SiGe-LSI with multifunctions.