To form the barrier layer for preventing a reaction of the ZrO{sub}2 gate dielectrics with the poly-Si gate, we investigated the annealing effects of NH{sub}3 and SiCl{sub}4 gases on ZrO{sub}2. These are the typical source gases for the atomic-layer deposition (ALD) of Si nitride on Si or SiO{sub}2 substrates. The introduced Si during the SiCl{sub}4 exposure preferentially exist near the surface of ZrO{sub}2. No nitrogen exists around the surface after the alternate exposure of NH{sub}3 and SiCl{sub}4. The introduced Si atoms found to form SiO{sub}2 and substoichiometric Zr silicate, which suggests a reaction with the introduced nitrogen during the subsequent NH{sub}3 exposure. Therefore, at least using NH{sub}4 and SiCl{sub}4. Si nitride barrier layer formation by ALD is difficult on ZrO{sub}2.
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