NOVELTY - Etching composition (I), comprises an aqueous solution of at least a quaternary ammonium fluoride salt (a).    USE - (I) is useful for the etching of inorganic layers in the production of photovoltaic or semiconducting devices (claimed), preferably selective emitter solar cells, passivated emitter rear locally diffused-solar cells, passivated emitter rear contact-solar cells, passivated emitter rear totally diffused-solar cells, interdigitated back contact cells and bifacial solar cells.    ADVANTAGE - (I): shows no or very low etching capability during storage and printing; and provides contactless application, hence good for patterning fragile substrates. The method: provides local deposition in combination with a low consumption of process chemicals; cut downs the number of process steps essentially needed for surface structuring (has three major process steps, where photolithography requires at least eight process steps); is a digital technique, hence images can be easily manipulated and a printer can be used to print rapidly a range of different patterns; provides better resolution than screen printing; and is a efficient method in the utilization of material, cost-saving and environment-friendly.    DETAILED DESCRIPTION - Etching composition (I), comprises an aqueous solution of at least a quaternary ammonium fluoride salt of formula (R1R2R3R4N+F-) (a).    R1 = -CHYa-CHYbYc, which consists of groups, where 2, 3 or 4 of the nitrogen attachments form part of a ring or a ring system;    Ya-Yc = H, alkyl or (hetero)aryl; and    R2-R4 = R1 or alkyl, alkylammoniumfluoride, (hetero)aryl or -CHYa-CHYbYc.    Provided that: by elimination of H in -CHYa-CHYbYc volatile molecules are generated. An INDEPENDENT CLAIM is also included for a method for the etching of inorganic layers in the production of photovoltaic or semiconducting devices, comprising: contactless application of (I) onto the surface to be etched; and heating the applied (I) to generate or activate the active etchant and etching the exposed surface areas of functional layers.