Method and system for non-destructive metrology of thin layers

An x-ray photoelectron spectroscopy (XPS) system for determining a property of a layer of an integrated circuit (IC), the layer being formed over a patterned underlayer, the XPS system comprises:

• an x-ray source configured to irradiate a non-flat topology of the IC to thereby generate emission from the IC;
• an analyzer configured to collect the emission from the IC;
• and
• a processing system that is configured to:
• determine the kinetic energy of emitted species within the emission to thereby calculate emission intensity of various species emitted from the layer and emission intensity of species emitted from the underlayer;
• obtain from an optical critical dimension (OCD) tool parameters of repetitive pattern of the non-flat topology;
• and
• use the ratio together with the parameters of the repetitive pattern to determine material composition and/or thickness of the layer.