Abstract:
In this study, the structural, electronic, and born-effective charge properties of silicon (Si) doped
were investigated with respect to density functional theory by using the Quantum Espresso
Package. The local density approximation (LDA) and the generalized gradient approximation
(GGA) were used to compute the exchange correlation energy. The total minimum energy of
hafnium oxide is determined as a function of cutoff energy and Monk Horst-Pack grid size. The
results show that the total minimum energy per atom is monotonically decreasing with increasing
cutoff energy due to the variational principle. The total minimum energy is converged at the 5 X 5
X 5 k-point cutoff 35 Rydberg and Monk horst-pack mesh. Furthermore, the lattice parameter is
taken from the literature. Our materials' lattice parameters are a = 5.14Å, b = 5.19Å, and c =
5.32Å. This result is in good agreement with the experimental value. Finally, structural, electronic,
and born-effective charge properties are calculated for pure and silicon-doped hafnium oxide. The
results show that after silicon dope, the band is changed from indirect band gap to direct band
gap, and the value of the band gap is decreased because of lattice distortion after silicon dope.
One hafnium atom is substituted by a silicon atom because hafnium is more stable than oxygen.
The doped-born effective charge shows a large value when we compare with pure hafnium oxide,
and it makes a great contribution to the dielectric response