First principles investigation of charge transition levels in monoclinic, orthorhombic, tetragonal, and cubic crystallographic phases of HfO2
Md Nur K. Alam, Sergiu Clima, Barry O’Sullivan, B. Kaczer, Geoffrey Pourtois, Marc Heyns, Jan Van Houdt
Abstract
A first-principles study of native point defects in monoclinic, cubic, two different tetragonal, and five different orthorhombic phases of hafnia (HfO2) is presented. They include vacancy of tri-coordinated and tetra-coordinated oxygen, metal vacancy, interstitial metal, and interstitial oxygen. Defect formation energy, trap depth, and relaxation energy upon optical excitation of defects are listed. The trap depth of oxygen vacancies shows little variation among different phases compared to other defects. Results of the trap depth are compared against measurements and found to have reasonable agreement.
Topics & Concepts
Monoclinic crystal systemTetragonal crystal systemOrthorhombic crystal systemMaterials scienceVacancy defectCrystallographyCrystallographic defectHafniaCondensed matter physicsChemistryCrystal structureMetallurgyPhysicsCubic zirconiaCeramicSemiconductor materials and devicesFerroelectric and Negative Capacitance DevicesElectronic and Structural Properties of Oxides