Thickness measurement of a thin hetero-oxide film with an interfacial oxide layer by X-ray photoelectron spectroscopy

► Thickness of the HfO2 layers in HfO2/SiO2/Si(1 0 0) films were measured by XPS. ► The contribution of the interfacial SiO2 layer to the thickness of the HfO2 overlayer was counterbalanced. ► The thickness levels of the HfO2 overlayers showed a small standard deviation of 0.03 nm in a series of HfO2/SiO2/Si(1 0 0) films. ► The thickness of HfO2 overlayers in a series of HfO2/SiO2/Si(1 0 0) films was verified by mutual calibration with XPS and TEM. ► The effective attenuation length of the photoelectrons could be determined.