X-ray metrology for advanced silicon processes

X-ray reflectivity (XRR), X-ray fluorescence (XRF) and small angle X-ray scattering (SAXS) techniques are used to the monitoring of Cu/ porous low k processes, which are developed for the next generation ( 65 nm) integrated circuits. Sensitivity of XRR and XRF is sufficient to detect drifts of the copper barrier layer, copper seed layer and Cu CMP (chemical–mechanical polishing) processes. Their metrology key parameters comply with production requirements. SAXS allows determining the pore structure of low k films: average pore size and pore size distribution