Material research express

The fundamental tradeoff has made it difficult to enhance the low permittivity of wide bandgap semiconductors without sacrificing the bandgap. In this work we demonstrate that high-concentration substitutional Be doping can enhance NiO's dielectric properties and simultaneously widen the bandgap. Up to 20 at% of Ni in NiO could be substituted by Be while maintaining the rocksalt crystalline structure. The real part of permittivity at low frequencies was found to be significantly increases (40%) while bandgap also increases from 3.06 to 3.37. These findings offer engineering insights for developing high-K wide bandgap materials, essential for various electronic and optoelectronic applications.