NOVELTY - Thin layer solar module (1) exhibiting several serially connected thin layer solar cells (11), for producing photovoltaic energy, comprises two substrates (2, 10) which are interconnected by an adhesive layer. The solar cells exhibit a layer structure arranged between the two substrates, containing a first electrode layer (5), a second electrode layer, and a semi-conductor layer (6), which is arranged between both electrode layers. The semi-conductor layer forms a p-n-junction and is doped with a doping material. The adhesive layer exhibits a specific amount of doping material.    USE - The adhesive layer in the thin layer solar module is useful such that the adhesive layer exhibits a certain amount of doping material so that the doping material from the semi-conductor layer is prevented from diffusing into the adhesive layer, the adhesive layer containing sodium (0.1-4 wt.%) in a thin layer solar module is useful for suppressing the diffusion of sodium from a sodium-doped semiconductor layer, preferably from a sodium-doped Cu(In, Ga) (S, Se)2 layer, into the adhesive layer (all claimed).    ADVANTAGE - The thin layer solar module is resistant to aging- and adverse weather conditions and achieves low manufacturing cost.    DETAILED DESCRIPTION - Thin layered solar module (1) exhibiting several serially connected thin layer solar cells (11), for producing photovoltaic energy, comprises two substrates (2, 10) which are interconnected by an adhesive layer. The solar cells exhibit a layer structure arranged between the two substrates, containing a first electrode layer (5), a second electrode layer, and a semi-conductor layer (6) which is arranged between both electrode layers. The semi-conductor layer forms a p-n-junction and is doped with a doping material. The adhesive layer exhibits a certain amount of doping material such that the doping material from the semi-conductor layer is prevented from diffusing into the adhesive layer. An INDEPENDENT CLAIM is also included for producing a thin layered solar module, comprising (i) providing a layer structure arranged between the two substrates, containing a first electrode layer, a second electrode layer, and a semi-conductor layer, where the semi-conductor layer forms a p-n-junction and is doped with a doping material, and (ii) joining the two substrates with an adhesive layer using heat, vacuum and/or pressure, where the adhesive layer exhibits a certain amount of doping material such that the doping material from the semi-conductor layer is prevented from diffusing into the adhesive layer.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic cross-sectional view of the thin layer solar cell.    Thin layer solar module (1)    Two substrates (2, 10)    First electrode layer (5)    Semi-conductor layer (6)    Thin layer solar cells (11)