Theoretical Calculation and Experimental Verification of the Hf/Al Concentration Ratio in Nano-mixed HfxAlyOz Films Prepared by Atomic Layer Deposition

We have proposed a characteristic method to estimate real composition when multi component oxide films are deposited by ALD. Final atomic concentration ratio was theoretically calculated from the film densities and growth rates for HfO₂and Al₂O₃using ALD processed HfxAlyOz films. We have transformed initial source feeding ratio during deposition to final atomic ratio in HfxAlyOz films through thickness factors (R_(HfO₂) and R_(Al₂O₃)) and concentration factor(C) defined in our experiments. Initial source feeding ratio could be transformed into the thickness ratio by each thickness factor. Final atomic ratio was calculated from thickness ratio by concentration factor. It has been successfully confirmed that the predicted atomic ratio was in good agreement with the actual measured value by ICP-MS analysis.