Structural and optical properties of carbon contaminated HfO2: First principle study

The role of substitution carbon defect on the structural properties and dielectric constant of monoclinic hafnium dioxide was investigated by adopting density functional theory calculations. Local vibration modes for various doping mechanisms of carbon have also included in the calculations. Results show that carbon substitution for oxygen is more energetically favorable than substitution for hafnium. Additionally, carbon has an anisotropic and divergent impact upon the dielectric constant based upon hosted site. For oxygen site, the dielectric constant achieves 4.709, whereas it decreases to 4.128 for the case of both hafnium sites. Calculated vibrational frequencies (836.09, 862.39 and 1507.64 and 1508.55) provide valuable information toward verifying the existence of carbon in m-HfO 2 .