A layer of the mixture that contains polymer and conductive particles is applied over a first surface, when the mixture has a first viscosity that allows the conductive particles to rearrange within the layer. An electric field is applied over the layer, so that a number of the conductive particles are aligned with the field and thereafter the viscosity of the layer is changed to a second, higher viscosity, in order to mechanically stabilise the layer. This leads to a stable layer with enhanced and anisotropic conductivity.