Surface and morphological studies of LiNbO3: p-type semiconductivity on stoichiometric surfaces

LiNbO3 is a semiconductor material employed in the development of several technological devices and processes. However, its suitability is expanded when p-type semiconductivity is obtained. In this work, density functional theory (DFT) simulations using the B3LYP hybrid functional connect the surface and crystalline morphology of LiNbO3 to its semiconductivity features. Thus, the main low-index surfaces were carefully investigated, presenting the influence of O vacancies on surface stability and structural and electronic features. The results also illustrate the electronic properties of surfaces in terms of band gap, charge carrier stability, and semiconductor type, the latter being dependent on the surface direction. Finally, a large set of possible crystalline morphologies for LiNbO3 is presented, predicting the expected properties for different crystal shapes from the calculated surface properties. A particular behavior is found observing the existence of both p- and n-type semiconductivity in the same morphology.

Automated summary

LiNbO3 is a semiconductor material used in the development of technological devices and processes, with its suitability expanded when it exhibits p-type semiconductivity. Density functional theory simulations connect the surface and crystalline morphology of LiNbO3 to its semiconductor features, providing insights on the influence of O vacancies on surface stability and electronic properties. The study also predicts the expected properties of different crystal shapes based on calculated surface properties, revealing a special behavior of both p- and n-type semiconductivity in the same morphology.