フィルタードアークイオンプレーティング法により形成したＤＬＣ膜のナノメータスケールの機械特性

Abstract

DLC (Diamond like carbon) films are deposited by bend type filtered cathodic vacuum arc (FCVA) technique with argon gas and a graphite target. Mechanical properties, such as nanoindentation hardness and nanowear resistance dependence on bias voltage, are evaluated by atomic force microscopy (AFM). The bend type FCVA is efficient for depositing low surface roughness DLC films free of microparticles. Ion energy, controlled by the substrate bias, is an important parameter in determining the mechanical properties of films deposited by FCVA. The substrate was subjected to DC or pulse bias voltage for film deposition. The modulus of dissipation and E/H decreases as nanoindentation hardness increases. In nanoindentation tests, property deposited FCVA films showed a higher hardness, a lower modulus of dissipation energy and a lower material factor of plastic index E/H, than those of sputtered and ion planting DLC films. The maximum hardness and Young's modulus values for DLC film deposited at a bias voltage of −50V DC were observed. According to the nanowear tests by AFM (atomic force microscope), the atomic scale wear was evaluated, and the correlation between microwear, hardness, modulus of dissipation and E/H are verified. The hardest DLC film shows the lowest wear; therefore, fewer dissipated permanent deformations such as cracks or dislocations were caused by nanoindentation and microwear. FCVA DLC films deposited at a proper bias voltage, like −50V DC bias voltage, show excellent nanometerscale mechanical properties.