First-principles calculations-based model for the reactive ion etching of metal oxide surfaces

A model for the RIE process design of metal oxide surfaces based on density functional theory-based total energy calculations has been developed. Cluster and periodic systems were employed in order to develop the model and hence gain a deeper understanding of the process mechanisms on an atomic scale. In the present study, Fe₃O₄ was used for the cluster system, and NiO for the periodic system as metal oxide surfaces. Possible gas combinations and by-products were studied with the aim of producing a more efficient and effective RIE process for metal oxide thin films. This study can be considered as fundamental groundwork required for the understanding of the reactivity in the etching of metal oxide surfaces and a means of decreasing the processing period of RIE for metal oxide thin films by optimum selection of gas combinations with a knowledge of their probable by-products.