Evaluation of Strained Silicon by Electron Back Scattering Pattern Compared with Raman Measurement and Edge Force Model Calculation

Abstract

Global and local strained-Si samples, namely strained-Si on insulator (SSOI) wafer and a Si substrate with a patterned SiN film were each evaluated by electron backscattering pattern (EBSP). In the EBSP measurements for SSOI, biaxial tensile stresses (biaxial tensile strains and compressive strain perpendicular to the surface) were obtained, whose values were consistent with those obtained by UV-Raman spectroscopy. One-dimensional stress distributions in the Si substrate with the patterned SiN film were obtained by EBSP, UV-Raman spectroscopy with a deconvolution method, and edge force model calculation. The results were well consistent with each other. EBSP allows us to measure stress and strain in the patterned SiN sample with 150-nm wide space. Furthermore, anisotropic biaxial stress including shear stress was also obtained by EBSP.