Diamond-like carbon (DLC) layers have excellent mechanical properties such as high hardness, high modulus of elasticity and low friction coefficient. They show an anti-adhesive effect in interaction with soft material surfaces. These properties make DLC films interesting for industrial application on tools and sliding machine parts. The utilization of DLC films for industry requires deposition technologies for the preparation of layers on large-area and three-dimensional substrates. A microwave plasma method using one or two electron cyclotron resonance plasma sources for large-area and three-dimensional deposition of DLC films is described. This method allows a wide variation of deposition parameters so that important properties of the films such as elasticity can be varied intentionally. Good adhesion is possible on large areas and surfaces with complicated geometry without an interface layer. The microhardness, wear and sliding behaviour of DLC films on different substrate materials were investigated. Results of measurements of mechanical film properties are explained. Furthermore, concrete examples of industrial applications of DLC layers are given.