Ferroelectric behaviours of ultra-nano-crystalline diamond thin films

The ferroelectric behaviour of ultra-nano-crystalline diamond (UNCD) thin films with low content nitrogen (< 1 at.%) is investigated by measuring the electrical, mechanical, Raman and X-ray photoemission spectroscopy. The electrical measurements I-V curve shows that the films doped with low content nitrogen possessed n-type conduction with ferro-electric behaviour at room temperature. The degree of ferroelectric behaviour changes with small change of nitrogen content incorporated in the film structure. The mechanical and microstructural properties are consistent with electrical measurements and these UNCD could be used in non-volatile memory devices.