Traceable Thickness Measurement of nm Oxide Films by Mutual Calibration

Mutual calibration has been known to be a traceable method to determine the absolute thickness of nm oxide films Recently, the thicknesses of a serious of ultra-thin HfO2 films were compared in a CCQM pilot study P-190 by 11 NMIs using various thickness measurement methods. The reference thicknesses of the films were precisely determined by mutual calibration by the average thickness of x-ray photoelectron spectroscopy (XPS) and x-ray reflectometry (XRR) data. The film thicknesses were also measured by medium energy ion scattering spectroscopy (MEIS). The film thicknesses measured by MEIS were linearly proportional to the reference thicknesses and the thickness difference was about 2%.