Oxygen is well known to play a significant role in the barrier behavior of titanium nitride layers for the IC metallization. TiN thin films are deposited by rapid thermal low pressure chemical vapor deposition from the TiCl{sub}4-NH{sub}3-H{sub}2gaseous phase onto silicon substrate. Oxygen contamination level lies in the range of 3.5-10 when the deposition temperature decreases from 800-500℃. The aim of this paper is to localize oxygen in the layer by a variety of complementary analyticaltechniques: Rutherford backscattering spectrometry. nuclear reactive analysis. Auger electron spectroscopy. X-ray photoelectron spectroscopy X-ray diffraction and scanning electron microscopy. These analyses show that O is diffused in the film from thesurface, and for low temperature films, O is most present at the interface TiN/Si. With small O contents (<3), this contamination is situated at grain boundaries, and for higher contents. O is diffused in the grains. For high temperatures, a columnarstructure is observed, and for low temperatures, a granular structure is observed. The layers are covered by copper and work well as a diffusion barrier between copper and silicon.
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