Control of electronic properties of HfO2 with fluorine doping from first-principles

The authors investigate the effect of the fluorine doping on the electronic properties of HfO2 in order to realize the perfect passivation of oxygen vacancy (Vo) with no excess charges, and with no band gap narrowing. Introducing of substitutional fluorine (Fs) can avoid deterioration in a gate oxide caused due to oxygen vacancies. However, introduction of fluorine alone adversely induces excess charges in gate oxide. Our calculated results provide new several dopants to control the electronic properties of HfO2 in purpose of achieving a large energy gain for the most stable state, no band gap narrowing, and also no excess charges. Here, two dopant pairs, Fs–Ns, and Fs–Als, are proposed.