Method for producing a thin-film solar module

A method for producing a thin-film solar module with serially connected solar cells, the method comprising:

• providing a substrate, wherein the substrate is flat;
• depositing a back electrode layer on one side of the substrate;
• subdividing at least the back electrode layer by first patterning trenches;
• depositing an absorber layer over the back electrode layer;
• subdividing at least the absorber layer by second patterning trenches;
• depositing a front electrode layer over the absorber layer;
• and subdividing at least the front electrode layer by third patterning trenches,
• wherein
• a patterning zone is formed by a succession of a first patterning trench,
• a second patterning trench, and two adjacent third patterning trenches,
• the two adjacent third patterning trenches are formed by laser ablation with a pulsed laser beam, and
• one third patterning trench of the two adjacent third patterning trenches of the patterning zone is formed with laser pulses of higher energy and the other third patterning trench of the two adjacent third patterning trenches of the patterning zone is formed with laser pulses of lower energy;
• wherein the absorber layer is not completely subdivided by the two adjacent third patterning trenches, such that the two adjacent third patterning trenches each extend into the absorber layer but not all the way to a substrate-side interface of the absorber layer.