C.M. Lopez, N.A. Suvorova, E.A. Irene, A.A. Suvorova, M. Saunders

ZrO₂ film interfaces with Si and SiO₂

Journal of Applied Physics 98 (2005) 033506

The interface formed by the thermal oxidation of sputter-deposited Zr metal onto Si(100)- and SiO₂-coated Si(100) wafers was studied in situ and in real time using spectroscopic ellipsometry (SE) in the 1.5–4.5 photon energy range and mass spectrometry of recoiled ions (MSRI). SE yielded optical properties for the film and interface and MSRI yielded film and interface composition. An optical model was developed and verified using transmission electron microscopy. Interfacial reaction of the ZrO₂ was observed for both substrates, with more interaction for Si substrates. Equivalent oxide thicknesses and interface trap levels were determined on capacitors with lower trap levels found on samples with a thicker SiO₂ underlayer. In addition to the optical properties for the intermixed interface layer, the optical properties for Zr metal and unreacted ZrO₂ are also reported.

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Cited Articles

1. Franta D., Ohlídal I.,
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