The description is of a flat substrate with an electrically conductive structure integrated inside the flat substrate or applied to a surface of the flat substrate and/or with a technically improved surface.The invention is characterised in that at least one sensor is integrated inside the flat substrate or applied to a surface of the flat substrate, which generates sensor signals according to deformations occurring inside the flat substrate, at least one actuator is integrated inside the flat substrate or applied to the surface of the flat substrate, which enables the flat substrate to mechanically deform when activated, and a signal unit connected to the at least one sensor and to the at least one actuator is provided, which, on the basis of the sensor signals, generates actuator signals for activating the actuator, so that deformations occurring inside the flat substrate are reduced.