Described is a method of manufacturing a module with long-term stability even though it contains a non-heat-resistant material, in particular a photosensitizer. Two glass plates (1, 2) are connected to each other round their edges with an edge-sealing structure made from glass solder. The non-heat-resistant material is subsequently (i.e. after the glass plates have been heat-sealed) pumped into the sealed module through at least one suitably shaped feed aperture (78.1). Selective coating with glass solder enables linear ribs (10.1, 10.2, 10.3, 11.1, 11.2, 11.3) to be produced in order to form spatially discrete chambers. When being joined by heat-sealing, at least one of the glass plates is heated to a temperature in the region of, or above, the transformation temperature of the plate in order to ensure that the plates (1, 2) are levelled or the distance between them is minimized.