THICKNESS DETERMINATION OF THIN SIO2 ON SILICON

The thicknesses of oxides on Si in the range 50-200 angstrom were determined. Ellipsometry, C-V measurements and transmission electron microscopy as well as Fowler-Nordheim tunnelling were employed. A thorough estimation of systematic and pure measuring errors was done for all results. For the extraction of the oxide-thickness from C-V measurements a new simple formula is suggested. The comparison of the different techniques shows very good agreement of the data within 2 angstrom for oxides without roughness. For rough oxides the agreement is still good for ellipsometry and C-V, both methods integrating over a large area.