A multijunction solar cell including a first solar subcell having a first band gap and a first short-circuit current; a second solar subcell disposed over the first solar subcell and having a second band gap greater than the first band gap and a second short-circuit current greater than the first short-circuit current by an amount in the range of 2% to 6%; a third solar subcell disposed over the second solar subcell and having a third band gap greater than the second band gap and a third short-circuit current less than the first short-circuit current by an amount in the range of 2% to 6%; and a fourth solar subcell disposed over the third solar subcell having a fourth band gap greater than the third band gap, and a fourth short-circuit current less than the third short-circuit current by an amount in the range of 6% to 10%, so that at an end of life state of the multijunction solar cell in an AM0 space environment the short-circuit current of each of the subcells are substantially identical.

Manufacture of multi junction solar cells, and devices thereof, are disclosed. The architectures are also adapted to provide for a more uniform and consistent fabrication of the solar cell structures, leading to improved yields, greater efficiency, and lower costs. Certain solar cells may be from a different manufacturing processes and further include one or more compositional gradients of one or more semiconductor elements in one or more semiconductor layers, resulting in a more optimal solar cell device.

The disclosure describes multi-junction solar cell structures that include two or more graded interlayers.

A solar cell has a condenser lens and a solar cell element, the solar cell element including an n-type InGaAs layer, an n-type GaAs layer, an n-type InGaP layer, the first InGaAs peripheral part having a thickness (d2), and a width (w2), the second InGaAs peripheral part having a thickness (d3), and a width (w3), the first GaAs peripheral part having a thickness (d5), and a width (w4), the second GaAs peripheral part a thickness (d6), and a width (w5), the first InGaP peripheral part having a thickness (d8), and a width (w6), the second InGaP peripheral part having a thickness (d9), and a width (w7), the following inequation set being satisfied: 1 nm(d2, d3, d5, and d6)4 nm, 1 nm(d8 and d9)5 nm, 100 nm(w2, w3, w4, w5, w6, and w7), the InGaAs center part having a thickness (w1), a window layer has a range S irradiated by sunlight having a width (w8); w8w1.

Methods and structures are provided for formation of devices, e.g., solar cells, on substrates including, e.g., lattice-mismatched materials, by the use of aspect ratio trapping and epitaxial layer overgrowth. A method includes forming an opening in a masking layer disposed over a substrate that includes a first semiconductor material. A first layer, which includes a second semiconductor material lattice-mismatched to the first semiconductor material, is formed within the opening. The first layer has a thickness sufficient to extend above a top surface of the masking layer. A second layer, which includes the second semiconductor material, is formed on the first layer and over at least a portion of the masking layer. A vertical growth rate of the first layer is greater than a lateral growth rate of the first layer and a lateral growth rate of the second layer is greater than a vertical growth rate of the second layer.

A multijunction solar cell assembly and its method of manufacture including interconnected first and second discrete semiconductor body subassemblies disposed adjacent and parallel to each other, each semiconductor body subassembly including first top subcell, second (and possibly third) lattice matched middle subcells; a graded interlayer adjacent to the last middle solar subcell; and a bottom solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the last middle solar subcell; wherein the interconnected subassemblies form at least a four junction solar cell by a series connection being formed between the bottom solar subcell in the first semiconductor body and the bottom solar subcell in the second semiconductor body.

A solar cell including a sequence of layers of semiconductor material forming a solar cell; a metal contact layer over said sequence of layers; a permanent supporting substrate composed of a carbon fiber reinforced polymer utilizing a conductive polyimide binding resin disposed directly over said metal contact layer and permanently bonding thereto.

A multijunction solar cell assembly and its method of manufacture including first and second discrete semiconductor body subassemblies, each semiconductor body subassembly including first, second and third lattice matched subcells; a graded interlayer adjacent to the third solar subcell and functioning as a lateral conduction layer; and a fourth solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the third solar subcell; wherein the average band gap of all four cells is greater than 1.44 eV.

A multi-junction solar cell that is lattice-matched with a base, and that includes a sub-cell having a desirable band gap is provided. A plurality of sub-cells are laminated, each including first and second compound semiconductor layers. At least one predetermined sub-cell is configured of first layers and a second layer. In each of the first layers, a 1-A layer and a 1-B layer are laminated. In the second layer, a 2-A layer and a 2-B layer are laminated. A composition A of the 1-A layer and the 2-A layer is determined based on a value of a band gap of the predetermined sub-cell. A composition B of the 1-B layer and the 2-B layer is determined based on a difference between a base lattice constant of the base and a lattice constant of the composition A. Thicknesses of 1-B layer and 2-B layer are determined based on difference between base lattice constant and a lattice constant of composition B, and on thickness of the 1-A layer and thickness of 2-A layer.