A stacked multi-junction solar cell with a back-contacted front side, having a germanium substrate that forms a rear side of the multi-junction solar cell, a germanium sub-cell and at least two III-V sub-cells, successively in the named order, and at least one passage contact opening that extends from the front side of the multi-junction solar cell through the sub-cells to the rear side and a metallic connection contact that is guided through the passage contact opening. A diameter of the passage contact opening decreases in steps from the front side to the rear side of the multi-junction solar cell. The front side of the germanium sub-cell forms a first step having a first tread depth that circumferentially projects into the passage contact opening. The second step with a second tread depth circumferentially projects into the passage contact opening.

A method for structuring an insulating layer on a semiconductor wafer, at least comprising the steps of: Provision of a semiconductor wafer with a top, a bottom and comprising multiple solar cell stacks, wherein each solar cell stack is a Ge substrate, which forms the bottom of the semiconductor wafer, a Ge subcell and at least two III-V subcells, in the above order, and at least one passage opening, which extends from the top to the bottom of the semiconductor wafer and has a connected side wall, an insulating layer two-dimensionally deposited on the top of the semiconductor wafer, on the side wall of the passage opening and/or on the bottom of the semiconductor wafer, and the deposition of an etch-resistant filling material by means of a printing process on an area of the top which comprises the passage opening, and into the passage opening.

A method for structuring an insulating layer on a semiconductor wafer, at least comprising the steps of: Provision of a semiconductor wafer with a top, a bottom and comprising multiple solar cell stacks, wherein each solar cell stack is a Ge substrate, which forms the bottom of the semiconductor wafer, a Ge subcell and at least two III-V subcells, in the above order, and at least one passage opening, which extends from the top to the bottom of the semiconductor wafer and has a connected side wall, an insulating layer two-dimensionally deposited on the top of the semiconductor wafer, on the side wall of the passage opening and/or on the bottom of the semiconductor wafer, and the deposition of an etch-resistant filling material by means of a printing process on an area of the top which comprises the passage opening, and into the passage opening.

A paste (32) for use in metallization of a solar cell (12) includes an organic vehicle (44) and a mixture of copper-containing particles (46), metal-oxide-containing nanoparticles (50), and secondary oxide particles (52) different from the metal-oxide-containing nanoparticles (50). The secondary oxide particles (52) include particles (42) of a metal oxide and a metal of the metal oxide capable of reducing at least some of the metal-oxide-containing nanoparticles (50) to metal when heated. The organic vehicle (44) is capable of reducing the metal oxide of the secondary oxide particles (52) upon decomposition of the organic vehicle (44). A paste (32) includes a mixture of particles (42) including metallic copper particles (46), nanoparticles (50), and metal oxide particles (52) in the organic vehicle (44). The nanoparticles (50) include at least one oxide of nickel, copper, cobalt, manganese, and lead. The metal oxide of the metal oxide particles (52) has a more negative Gibbs Free Energy of Formation than a metal oxide of the at least one oxide of the nanoparticles (50).

A method for plating by means of a through-hole on a semiconductor wafer at least comprising the steps: providing a semiconductor wafer having a top side and a bottom side, wherein the semiconductor wafer has a plurality of solar cell stacks and comprises a substrate on the bottom side, and each solar cell stack has at least two III-V subcells, disposed on the substrate, and at least one through-hole, extending from the top side to the bottom side of the semiconductor wafer, with a continuous side wall, wherein the through-hole has a first edge region on the top side and a second edge region on the bottom side; applying an insulating layer to part of the first edge region, the side wall, and to the second edge region by means of a first printing process; and applying an electrically conductive layer.

A stacked multijunction solar cell having a dielectric insulating layer system, a germanium substrate, which forms an underside of the multijunction solar cell, a germanium subcell and at least two III-V subcells, which follow each other in the specified order, the insulating layer system includes a layer sequence made up of at least one bottom insulating layer, which is integrally connected to a first surface section of the multijunction solar cell and a top insulating layer forming an upper side of the insulating layer system, and a metal coating of the multijunction solar cell is integrally and electrically conductively connected to a second surface section abutting the first surface section of the multijunction solar cell and is integrally connected to a section of the upper side of the insulating layer system, and the top insulating layer comprises amorphous silicon or is made up of amorphous silicon.

A solar cell module includes solar cells each including a semiconductor substrate and first and second electrodes that extend in a first direction on a surface of the semiconductor substrate and have different polarities; conductive lines extended in a second direction crossing the first direction on the surface of the semiconductor substrate included in each solar cell and connected to the first electrodes or the second electrodes through a conductive adhesive; and an insulating adhesive portion extending in the first direction on at least a portion of the surface of the semiconductor substrate, on which the conductive lines are disposed, and temporarily fixing the conductive lines to the semiconductor substrate and the first and second electrodes, the insulating adhesive portion being attached on a back surface of least a portion of each conductive line as well as a side surface of at least a portion of each conductive line.

A tandem solar cell includes a top solar cell and a bottom solar cell. The top solar cell and the bottom solar cell each have a respective front surface and a rear surface, with the respective front surfaces being adapted for facing a radiation source during use. The top solar cell is arranged with its rear surface overlying the front surface of the bottom solar cell. The top solar cell includes a photovoltaic absorber layer with a bandgap greater than that of crystalline silicon. The bottom solar cell includes a crystalline silicon substrate. On at least a portion of the front surface of the bottom solar cell a passivating layer stack is disposed which includes a thin dielectric film and a secondary layer of either selective carrier extracting material or polysilicon. The thin dielectric film is arranged between the silicon substrate and the secondary layer.

A photovoltaic module (1) with a plurality of photovoltaic units (3) each having a positive contact terminal (8) and a negative contact terminal (7), and a single layer back contact substrate (4). The back contact substrate (4) has a positive surface part (6) electrically connected to the positive contact terminal (8) of each of the plurality of photovoltaic units (3), and a negative surface part (5) electrically connected to the negative contact terminal (7) of each of the plurality of photovoltaic units (3). The photovoltaic module (1) further has at least one contact bridge (9a, 9b) in a layer of the photovoltaic module (1) outside of the single layer back contact substrate (4), which provides an electrical connection in the negative surface part (5) and/or in the positive surface part (6).

Photovoltaic module with a plurality of thin film photovoltaic cells (2). Each thin film photovoltaic cell (2) has a transparent electrode (12) provided on a transparent substrate (11), a solar cell stack (13) positioned on the transparent electrode (12), and a top electrode (14) positioned on the solar cell stack (13). A plurality of parallel connected PV cell units (3) are provided, each comprising a string of series connected PV cells (2). A positive connection part (6, 20a) and a negative connection part (5, 20b) are present in a single top interconnection layer, providing the parallel connection circuit of the parallel connected PV cell units (3). At least one cross over connection member (9a, 9b) is present in a layer different from the single top interconnection layer, which provides an electrical connection in the negative connection part (5, 20b) and/or in the positive connection part (6, 20a).