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C. Wyon1, J.P. Gonchond2, M. Hopstaken3, J. Bienacel2, R. Delsol3, P. Normandon2 and L.F.Tz. Kwakman3
1CEA-LETI, 2STMicroelectronics, 3Philips Semiconductors, 850, rue Jean Monnet, 38926 Crolles cedex, France

ABSTRACT

X-ray metrology techniques, which are hereafter defined as techniques using X-rays as the incident probe beam, are quickly moving from offline characterization laboratories to semiconductor fabrication lines. This article reviews applications of some X-ray metrology techniques to monitor FEOL and BEOL processes for the development of £ 65-nm technology nodes. In-line control of ultrathin nitrided gate oxides is performed using XPS, while the development of high-k dielectrics can be accelerated using XRR and XRF. XRR is used for controlling the formation of NiSi thin films, as well as the individual thickness of Ta/TaN barrier layer. Monitoring of Cu interconnects texture is realized using XRD. Combined XRR and SAXS can provide valuable information about the porosity and pore-size distribution of ultra low-k layers.