Submicron mapping of strained silicon-on-insulator features induced by shallow-trench-isolation structures

摘要

Real-space maps of strain within silicon-on-insulator (SOI) features induced by adjacent, embedded shallow-trench-isolation (STI) SiO_2 regions were obtained using x-ray microbeam diffraction. The quantitative strain mapping indicated that the SOI strain was largest at the SOI/STI interface and decreased as a function of distance from this interface. An out-of-plane residual strain of approximately -31με was observed in the blanket regions of the SOI. A comparison of the depth-averaged strain distributions to the strain profiles calculated from an Eshelby inclusion model indicated an equivalent eigenstrain of -0.55% in the STI regions acting on the SOI features.