(FR2690278-A1)      The solar cell includes two elementary cells (1, 2) one of which comprises a substrate (4) supporting an active layer (5) deposited over an intermediate soluble layer (12), the other cell comprising a second substrate and a second different active layer.    The two elementary cells are stuck to each other using a transparent insulating or conducting bonding substance depending on application. The first elementary cell is turned upside down so that its substrate constitutes the top of the structure. The structure is then immersed in dilute acid which removes the soluble layer leaving its substrate intact. Protecting layers (3, 5, 8, 9) are then deposited over the solar cell.    USE/ADVANTAGE -   For light conversion into electrical energy using photovoltaic effect. Has reduced weight eliminating one of substrates and associated vias. Improves thermal dissipation. Can be used on aircraft.    (JP6511357-W)      The solar cell includes two elementary cells (1, 2) one of which comprises a substrate (4) supporting an active layer (5) deposited over an intermediate soluble layer (12), the other cell comprising a second substrate and a second different active layer.    The two elementary cells are stuck to each other using a transparent insulating or conducting bonding substance depending on application. The first elementary cell is turned upside down so that its substrate constitutes the top of the structure. The structure is then immersed in dilute acid which removes the soluble layer leaving its substrate intact. Protecting layers (3, 5, 8, 9) are then deposited over the solar cell.    USE/ADVANTAGE -   For light conversion into electrical energy using photovoltaic effect. Has reduced weight eliminating one of substrates and associated vias. Improves thermal dissipation. Can be used on aircraft.    (US5458694-A)      A method of making a multi-spectral photovoltaic component comprising a stack of at least two elementary cells in association having different spectral response characteristics, the method being characterized by the following steps:    (a) producing a first cell (1) comprising a first substrate (4), a first optically active layer (5), and between said substrate and said active layer, a soluble thin layer (12);    (b) producing a second cell (2) comprising a second substrate (8) and a second optically active layer (9), different in nature from the first;    (c) placing said two cells face to face so that the active layers face each other;    (d) uniting the two elementary cells via their active layers by means of a transparent adhesive (3) in contact therewith; and    (e) dissolving the material of the soluble layer while leaving the other materials intact, thereby separating the first substrate from the remainder of the structure, without dissolving the first substrate.