X-RAY REFLECTIVITY MEASUEMENTS FOR DEPTH DENSITY DISTRIBUTION IN THERMAL OXIDE THIN FILM ON SILICON (100)

摘要

X-ray reflectometry (XRR) is a powerful tool for the structural characterization of thin films. However the standardized protocols of the measurements and their analyses need to be established for the reliable and reproducible characterization. The collaborative work between National Institute of Standards and Technology (NIST, USA) and National Metrology Institute of Japan (NMIJ, Japan) for thickness evaluation by XRR has been carried out in order to support the activities for the standardization of the thickness evaluation. In order to evaluate the accurate thickness of thin film structures by XRR experiments, the appropriate model construction of the structures should be required for the XRR data analysis. However there have been numerous discussions about the structures especially around the film/substrate interface. We tried to clarify a depth density distribution of a thermal oxide thin film on a Si substrate by comparing the XRR results obtained from several films which were oxidized by different processes.