Abstract
Diamond-like carbon (DLC) films are currently applied in various advanced field as magnetic disk protective layers. Mechanical endurance is difficult to maintain if a protective film is reduced to approximately 1.0 nm in thickness, which amounts to approximately several atomic layers. When considering such thin films, the corpuscular characteristics of the atomic bonding during friction and wear should be taken into account. It is difficult to maintain mechanical endurance when only several atomic layers of the protective film are involved. With the development of nanotechnology, the size of machinery is decreasing. Owing to the increasing importance of the properties of surfaces, the development of evaluation methods of the mechanical properties of DLC film surfaces is becoming indispensable. Future developments are expected as a result of current research and development. The mechanical properties of a few atomic protective layers should be evaluated. In this paper, the evaluation of the nanomechanical properties of nanometer scale surfaces is discussed and refer to our recent results on the evaluation of the nanomechanical properties of diamond-like carbon (DLC) films deposited by a bend type filtered cathodic vacuum arc (FCVA) and electron cyclotron resonance chemical vapour deposition (ECR-CVD) methods, nanoperiod multilayer films composed of DLC and other materials deposited by radio frequency (RF) sputtering, and a lubricant on DLC protective films. In the field of micro-nano technology, nanoscale evaluation technology is important for determining surface mechanical properties. The evaluation of thin-film surfaces has been performed by nanoindentation tests and nanoscratch tests using an atomic force microscopy. On the other hand, nanowear tests can evaluate the average mechanical properties of a thin-film, it has become possible to evaluate a difference of about 0.1 nm by choosing appropriate loads. The properties of vibrational wear, surface friction, viscoelastic properties and other dynamic properties can be evaluated by applying a force modulation method using scanning probe microscope (SPM). Moreover, it is effective to evaluate mechanical properties of surfaces. Surface friction durability has been studied by measuring the friction force and current distribution in vibration tests.
