A capacitor has a tantalum oxynitride film. One method for making the film comprises forming a bottom plate electrode and then forming a tantalum oxide film on the bottom plate electrode. Nitrogen is introduced to form a tantalum oxynitride film. A top plate electrode is formed on the tantalum oxynitride film. Embodiments include a method of operating an antifuse, comprising applying a voltage across electrodes of a capacitor having a tantalum oxynitride film and forming a hole in the tantalum oxynitride film.