High energy nitrogen ion-beam implantation induced nucleation and crystalline growth in amorphous carbon nitride films

High-energy N+ injection-induced crystallization in amorphous carbon nitride (a-CN) films were observed by injecting different N+ energies. Nano-clusters with sizes of 2-5 nm form during initial N+ implantation, accompanied by the appearance of crystalline particles. Most nanocrystalline grains exhibit the same crystallographic orientation and have lattice parameters consistent with graphite-like carbon nitride (g-C3N4). Raman spectrum and XPS analysis confirm the presence of sp2 hybridized C-N bonds in N+ implanted C-N films. Crystallization behavior and rate depend on N+ energy, and the mechanism and model of N+ irradiation-induced crystallization are discussed. High N+ implantation provides key factors for structural evolution: high bombardment ions and temperatures. At 15 keV, insufficient energy prevents grain crystallization, resulting in local disorder during growth. Increasing N+ energy (60 keV) reduces disorder in the a-matrix, promoting atomic rearrangement and aggregation of sp2 phase. Simultaneously, high energy N+ induces high temperatures, facilitating growth of nc g-C3N4.