A multijunction solar cell in accordance with an example implementation includes a growth substrate; a first solar subcell disposed over or in the growth substrate; a tunnel diode disposed over the first solar subcell; and a grading interlayer directly disposed over the tunnel diode; a sequence of layers of semiconductor material forming a solar cell disposed over the grading interlayer comprising a plurality of solar subcells. The multijunction solar cell also includes a first wafer bowing inhibition layer disposed directly over an uppermost sublayer of the grading interlayer, such bowing inhibition layer having an in-plane lattice constant greater than the in-plane lattice constant of the uppermost sublayer of the grading interlayer. A second wafer bowing inhibition layer is disposed directly over the first wafer bowing inhibition layer.

A method of fabricating a photovoltaic cell having a microinverter is provided. The method may include fabricating a monolithic microinverter layer through epitaxy and operably connecting the at least one microinverter layer to at least one photovoltaic cell formed on a photovoltaic layer. A photovoltaic device is also provided. The device may have a photovoltaic layer comprising at least one photovoltaic cell and a microinverter layer comprising at least one microinverter, wherein the microinverter layer was fabricated through epitaxy, the at least one microinverter is configured to be operably connected to at least one photovoltaic cell.

A semiconductor crystal substrate includes a crystal substrate that is formed of a material including one of GaSb and InAs, a first buffer layer that is formed on the crystal substrate and formed of a material including GaSb, and a second buffer layer that is formed on the first buffer layer and formed of a material including GaSb. The first buffer layer has a p-type conductivity, and the second buffer layer has an n-type conductivity.

A photodetector comprising a photoabsorber, comprising a doped semiconductor, a contact layer comprising a doped semiconductor and a barrier layer comprising a charge carrier compensated semiconductor, the barrier layer compensated by doping impurities such that it exhibits a valence band energy level substantially equal to the valence band energy level of the photo absorbing layer and a conduction band energy level exhibiting a significant band gap in relation to the conduction band of the photo absorbing layer, the barrier layer disposed between the photoabsorber and contact layers. The relationship between the photo absorbing layer and contact layer valence and conduction band energies and the barrier layer conduction and valance band energies is selected to facilitate minority carrier current flow while inhibiting majority carrier current flow between the contact and photo absorbing layers.

A multijunction solar cell with a graded interlayer disposed between two adjacent solar subcells, the graded interlayer being compositionally graded to lattice match a first solar subcell on one side, and an adjacent second solar subcell on the other side, the graded interlayer being composed of at least four step layers, a particular step layer having a lattice constant in the range of 0.2 to 1.2% greater than the lattice constant of the adjacent layer on which it is grown, and the subsequent steps layers disposed directly on the particular step layer having a lattice constant in the range of 0.1 to 0.6% greater than the particular layer on which it is grown, and wherein the thickness of the particular step layer is at least twice the thickness of each of the other subsequent step layers.

The present invention relates to a method of manufacturing semiconductor materials comprising interface layers of group III-V materials in combination with Si substrates. Especially the present invention is related to a method of manufacturing semiconductor materials comprising GaAs in combination with Si(111) substrates, wherein residual strain due to different thermal expansion coefficient of respective materials is counteracted by introducing added layer(s) compensating the residual strain.

A photovoltaic module, having: a substrate, a plurality of photovoltaic structures that are electrically connected to one another and extend over the substrate, each of which comprises at least one photovoltaic cell, and a multilayer electrical connection structure sandwiched between the substrate and the plurality of photovoltaic structures, forming at least one bypass diode for each photovoltaic structure, each bypass diode having: two electrodes electrically connected to the terminals of opposite polarity of the corresponding photovoltaic structure, at least one of the two electrodes extending at least partially underneath the corresponding photovoltaic structure, and a semiconductor portion in contact with the two electrodes via two separate surfaces.

A method of forming a multijunction solar cell that includes an InGaAs buffer layer and an InGaAlAs grading interlayer disposed below, and adjacent to, the InGaAs buffer layer. The grading interlayer achieves a transition in lattice constant from one solar subcell to another adjacent solar subcell.

An infrared detector and a method for forming it are provided. The detector includes absorber, barrier, and contact regions. The absorber region includes a first semiconductor material, with a first lattice constant, that produces charge carriers in response to infrared light. The barrier region is disposed on the absorber region and comprises a superlatice that includes (i) first barrier region layers comprising the first semiconductor material, and (ii) second barrier region layers comprising a second semiconductor material, different from, but lattice matched to, the first semiconductor material. The first and second barrier region layers are alternatingly arranged. The contact region is disposed on the barrier region and comprises a superlattice that includes (i) first contact region layers comprising the first semiconductor material, and (ii) second contact region layers comprising the second semiconductor material layer. The first and second contact region layers are alternatingly arranged.

Provided is a high-quality substrate including a silicon layer, a multilayer buffer layer on the silicon layer, and an indium phosphide (InP) layer on the multilayer buffer layer, wherein a crystal growth direction of the silicon layer is a direction inclined by 1° to 10° with respect to a vertical direction, and wherein the multilayer buffer layer includes a buffer layer in which a crystal growth direction is inclined with respect to the vertical direction.