LASER ETCHING A STACK OF THIN LAYERS FOR A CONNECTION OF A PHOTOVOLTAIC CELL

The invention concerns a treatment of thin layers (CIGS Mo) with a view to forming a connection of a photovoltaic cell (C1,C2) comprising said thin layers which comprise at least: * a first layer (CIGS) having photovoltaic properties deposited on a second layer (Mo) and * said second layer a metal contact layer deposited on a substrate (SUB). The following steps in particular are carried out: * etching into said first layer (CIGS) at least one first trench having a first width (L1) so as to expose the second layer (Mo); and * etching in said first trench a second trench so as to expose the substrate the second trench having a second width (L2) less than the first width (L1). The etching of the first and second trenches is moreover carried out by laser shots during a single overall etching step the method being characterised in that said overall etching step comprises: a fine etching operation close to fronts (FR1,FR2) intended to delimit the first trench; and a rough etching operation between the first and second fronts.