A method is described that includes sputtering multiple layers on a back surface of the photovoltaic structure, the photovoltaic structure being made of at least one group III-V semiconductor material, and evaporating, over the multiple layers, one or more additional layers including a metal layer, the back metal structure being formed by the multiple layers and the additional layers. A photovoltaic device is also described that includes a back metal structure disposed over a back surface of a photovoltaic structure made of a group III-V semiconductor material, the back metal structure including one or more evaporated layers disposed over multiple sputtered layers, the one or more evaporated layers including a metal layer. By allowing evaporation along with sputtering, tool size and costs can be reduced, including minimizing a number of vacuum breaks. Moreover, good yield and reliability, such as reducing dark line defects (DLDs), can also be achieved.

A method is described that includes sputtering multiple layers on a back surface of the photovoltaic structure, the photovoltaic structure being made of at least one group III-V semiconductor material, and evaporating, over the multiple layers, one or more additional layers including a metal layer, the back metal structure being formed by the multiple layers and the additional layers. A photovoltaic device is also described that includes a back metal structure disposed over a back surface of a photovoltaic structure made of a group III-V semiconductor material, the back metal structure including one or more evaporated layers disposed over multiple sputtered layers, the one or more evaporated layers including a metal layer. By allowing evaporation along with sputtering, tool size and costs can be reduced, including minimizing a number of vacuum breaks. Moreover, good yield and reliability, such as reducing dark line defects (DLDs), can also be achieved.

A PV device comprises a first mirror comprising a reflectance of higher than 50%; a second mirror interface; and an optical cavity positioned between the first mirror and the second mirror interface and comprising at least one IC stage. Each of the at least one IC stage comprises a conduction band; a valence band; a hole barrier comprising a first band gap; an absorption region coupled to the hole barrier, comprising a second band gap that is less than the first band gap, and configured to absorb photons; and an electron barrier coupled to the absorption region so that the absorption region is positioned between the hole barrier and the electron barrier. The electron barrier comprises a third band gap that is greater than the second band gap. The PV device is configured to operate at a forward bias voltage with a net photon absorption for generating an electric output.

A PV device comprises a first mirror comprising a reflectance of higher than 50%; a second mirror interface; and an optical cavity positioned between the first mirror and the second mirror interface and comprising at least one IC stage. Each of the at least one IC stage comprises a conduction band; a valence band; a hole barrier comprising a first band gap; an absorption region coupled to the hole barrier, comprising a second band gap that is less than the first band gap, and configured to absorb photons; and an electron barrier coupled to the absorption region so that the absorption region is positioned between the hole barrier and the electron barrier. The electron barrier comprises a third band gap that is greater than the second band gap. The PV device is configured to operate at a forward bias voltage with a net photon absorption for generating an electric output.

Systems and methods of non-epitaxial high Schottky barriers heterojunction solar cells are described. The high Schottky barriers heterojunction solar cells are formed using non-epitaxial methods to reduce fabrication costs and improve scalability.

Systems and methods of non-epitaxial high Schottky barriers heterojunction solar cells are described. The high Schottky barriers heterojunction solar cells are formed using non-epitaxial methods to reduce fabrication costs and improve scalability.

A multi junction solar cell includes one or more upper cells and a thin-film, polycrystalline, low-bandgap bottom cell. A single-junction solar cell includes a polycrystalline semiconductor thin film, wherein a bandgap of the solar cell is greater than 1.2 eV or less than 1.2 eV, and the solar cell is configured to receive light through two surfaces, such that the bottom cell has bifacial operation.

A multi junction solar cell includes one or more upper cells and a thin-film, polycrystalline, low-bandgap bottom cell. A single-junction solar cell includes a polycrystalline semiconductor thin film, wherein a bandgap of the solar cell is greater than 1.2 eV or less than 1.2 eV, and the solar cell is configured to receive light through two surfaces, such that the bottom cell has bifacial operation.

A monolithic metamorphic multi-junction solar cell comprising a first III-V subcell and a second III-V subcell and a third III-V subcell and a fourth Ge subcell, wherein the subcells are stacked on top of each other in the indicated order, and the first subcell forms the topmost subcell, and a metamorphic buffer is formed between the third subcell and the fourth subcell and all subcells each have an n-doped emitter layer and a p-doped base layer, and the emitter layer of the second subcell is greater than the base layer.

A monolithic metamorphic multi-junction solar cell comprising a first III-V subcell and a second III-V subcell and a third III-V subcell and a fourth Ge subcell, wherein the subcells are stacked on top of each other in the indicated order, and the first subcell forms the topmost subcell, and a metamorphic buffer is formed between the third subcell and the fourth subcell and all subcells each have an n-doped emitter layer and a p-doped base layer, and the emitter layer of the second subcell is greater than the base layer.