NOVELTY - Preparing electrically insulating or semiconducting substrate with electrically conductive pattern for an electric circuit involves: (a) providing the substrate comprising distribution of nanoparticles of first metal or its alloy; (b) i) locally applying layer of inhibiting material onto substrate; or ii) applying layer of inhibiting material onto the substrate, and locally removing or deactivating, light-induced, layer of inhibiting material to obtain the pattern; (c) depositing by means of electroless process layer of second metal or its alloy on substrate obtained in step (b).    USE - For preparing an electrically insulating or semiconducting substrate with an electrically conductive pattern for an electric circuit of electronic device (claimed) including flexible devices such as solar cells, displays, organic light emitting diodes (OLEDs) and interconnection parts or sensors for use in vehicles, computers, digital cameras and mobile phones.    ADVANTAGE - When the substrate is a foil it is particularly advantageous to carry out this method in a roll-to-roll fabrication process. Conventional methods, in which rigid substrates are used, are not suitable for roll-to-roll fabrication. The electric circuit comprising pattern and having submicron structures, is prepared by this method.    DETAILED DESCRIPTION - Preparing an electrically insulating or semiconducting substrate with an electrically conductive pattern for an electric circuit involves: (a) providing an electrically insulating or semiconducting substrate, which substrate comprises a distribution of nanoparticles of a first metal or its alloy; (b) i) locally applying a layer of an inhibiting material onto the substrate; or ii) applying a layer of an inhibiting material onto the substrate, and locally removing or deactivating, light-induced, thermally, chemically or electrochemically, the layer of inhibiting material and thereby exposing at least part of the first metal or its alloy so as to obtain a pattern for an electric circuit; (c) depositing by means of an electroless process a layer of a second metal or its alloy on the exposed part of the first metal or its alloy present in the substrate as obtained in step (b), whereby inhibiting material that is still present on the substrate after step (b) locally inhibits the second metal or its alloy to be deposited on the first metal or its alloy, ensuring that the second metal or its alloy will selectively be deposited on the exposed part of the first metal or its alloy as obtained in step (b).