ABSTRACT
We describe the stress analysis of silicon oxide (SiO2) thin film using cathodoluminescence (CL) spectroscopy and discuss its availability in this paper. To directly measure the CL spectra of the film under uniaxial tensile stresses, specially developed uniaxial tensile test equipment is used in a scanning electron microscope (SEM) equipped with a CL system. As tensile stress increases, the peak position and intensity proportionally increase. This indicates that CL spectroscopy is available as a stress measurement tool for SiO2 film. However, the electron beam (EB) irradiation time influences the intensity and full width at half maximum (FWHM), which implies that some damage originating from EB irradiation accumulates in the film. The analyses using Raman spectroscopy and transmission electron microscopy (TEM) demonstrate that EB irradiation for stress measurement with CL induces the formation of silicon (Si) nanocrystals into SiO2 film, indicating that CL stress analysis of the film is not nondestructive, but destructive inspection.
ABSTRACT
In this paper, in-situ cathodoluminescence (CL) stress analysis of a silicon oxide (SiO(x)) thin film prepared by wet thermal oxidation is described. The specially-developed uniaxial tensile loading jig was used to apply tensile displacement to the SiO(x) film specimen. CL spectra of the specimen during tensile loading were obtained, and the peak position of around 1.85 eV emission band was monitored for tensile stress analysis. The peak position gradually shifted towards higher/lower energy side when tensile displacement increased/decreased. The tensile stress-to-emission energy ratio of 6.21-8.97 x 10(2) GPa/eV was estimated on the basis of linear elastic theory, which demonstrated that CL is able to provide information on stress induced in the film. Scanning electron microscopy (SEM) revealed that the fracture of SiO(x) and SCS laminated structure occurred at the vicinity of SiO(x) film surface.