Characteristics of molybdenum nitride thin film by N2+ ion implantation

Molybdenum nitride thin films were prepared by N-2(+) implantation with acceleration energy of 20 KeV and the ion dose of 3x10(17) ions/cm(2). The structural property and thermal stability of the films were investigated by XRD, AES, AFM and RES. The crystal structure of N-2(+) implanted molybdenum thin films (Mo-N-2(+)) which had microcrystalline state was transformed to gamma-Mo2N phase with a preferred (111) orientation after a post-annealing at 500 degrees C for 30min. However, a silicide reaction was not observed even after the annealing at 700 degrees C, which is due to the modification of the interface between Mo thin film and Si substrate by N-2(+) implantation. Also, Cu diffusion did not seem to be induced by the annealing at 700 degrees C for 30 min. The internal stress of the Mo-N-2(+) thin films during post-annealing at 600 degrees C for 30min was found to change from highly compressive stress to low tensile stress.