We report on a comparative measurement of SiO2/Si dielectric film thickness (t < 10 nm) using grazing incidence x-ray photoelectron spectroscopy, neutron reflectometry, and spectroscopic ellipsometry. Samples with nominal thicknesses of 3 nm to 6 nm were characterized by XPS with grazing incidence x-rays at 1.8 keV, with cold neutron reflectometry (λ I = 0.475 nm), and with spectroscopic ellipsometry over 1.5 eV < E < 6.0 eV. The results show good agreement between the ellipsometry and the grazing incidence XPS, with slightly lower values for the neutron reflectometry. The effects of surface contamination are discussed.
Citation: Surface and Interface Analysis
Issue: No. 1
Pub Type: Journals
ellipsometry, GIXPS, grazing angles, neutron reflectometry, neutrons, reflectometry, silicon, silicon dioxide, x-rays