X-ray triple-axis diffractometry investigation of Si/SiGe/Si on silicon-on-insulator subjected to in situ low-temperature annealing

X-ray triple-axis diffractometry (XRTD) was used to characterize heterostructure Si/SiGe/Si on silicon-on-insulator (SOI) subjected to in situ low-temperature annealing. Crystallographic tilt, lattice constant and relaxation percentage were examined, respectively. Two peaks have been observed in (0 0 4) reciprocal lattice mappings (RLMs) of Si layers. The (0 0 4) RLMs indicate that Si cladding is in tensile strain. We have also found two peaks with different k∥ and k⊥ in (1 1 3) asymmetric RLMs of Si layers. It is deduced from comprehensive analyses on (0 0 4) and (1 1 3) RLMs that Ge diffusion and in-plane tensile strain lead to 2θ shift of the Si layers underneath SiGe layer in (0 0 4) RLMs. And the diffusion concentration of Ge accurately determined by XRTD is mole fraction 0.84%.