A method of fabricating a four junction solar cell having an upper first solar subcell composed of a semiconductor material including aluminum and having a first band gap; a second solar subcell adjacent to said first solar subcell and composed of a semiconductor material having a second band gap smaller than the first band gap and being lattice matched with the upper first solar subcell; a third solar subcell adjacent to said second solar subcell and composed of a semiconductor material having a third band gap smaller than the second band gap and being lattice matched with the second solar subcell; and a fourth solar subcell adjacent to and lattice matched with said third solar subcell and composed of a semiconductor material having a fourth band gap smaller than the third band gap; wherein the fourth subcell has a direct bandgap of greater than 0.75 eV.

Visibly transparent photovoltaic devices are disclosed, such as those are transparent to visible light but absorb near-infrared light and/or ultraviolet light. The photovoltaic devices make use of transparent electrodes and near-infrared absorbing visibly transparent photoactive compounds, optical materials, and/or buffer materials.

Disclosed are a solar cell including an upper cell includes an upper passivation layer disposed on an upper surface of a functional layer, a transparent electrode disposed on an upper surface of the upper passivation layer, an upper first charge transport layer disposed on an upper surface of the transparent electrode, an upper electrode disposed on the upper first of the transparent electrode to be adjacent to the upper surface charge transport layer, an upper second charge transport layer disposed on the upper surface of the functional layer to be spaced apart from the upper passivation layer, the transparent electrode, the upper first charge transport layer, and the upper electrode, and an upper absorption layer disposed on the upper passivation layer, the transparent electrode, the upper first charge transport layer, and the upper second charge transport layer.

Photovoltaic module comprising a plurality of multijunction photovoltaic cells, at least one of said multijunction photovoltaic cells comprising: a first photovoltaic sub-cell extending over a first predetermined area; a second photovoltaic sub-cell provided on said first photovoltaic sub-cell and in electrical connection therewith, said second photovoltaic sub-cell extending over a second predetermined area which is smaller than said first predetermined area so as to define at least one zone in which said first photovoltaic sub-cell is uncovered by said second photovoltaic sub-cell; an electrically-insulating layer situated upon said first photovoltaic sub-cell in at least a part of said zone; and an electrically-conductive layer situated upon at least part of said electrically-insulating layer and in electrical connection with a surface of said second photovoltaic sub-cell, wherein at least one of said multijunction photovoltaic cells is electrically connected to at least one other of said multijunction photovoltaic cells by means of at least one electrical interconnector electrically connected to said electrically-conductive layer in said zone.

A method and apparatus for reducing as-deposited and metastable defects relative to amorphous silicon (a-Si) thin films, its alloys and devices fabricated therefrom that include heating an earth shield positioned around a cathode in a parallel plate plasma chemical vapor deposition chamber to control a temperature of a showerhead in the deposition chamber in the range of 350° C. to 600° C. An anode in the deposition chamber is cooled to maintain a temperature in the range of 50° C. to 450° C. at the substrate that is positioned at the anode. In the apparatus, a heater is embedded within the earth shield and a cooling system is embedded within the anode.

A voltage matched multijunction solar cell having first and second solar cell stacks that are electrically connected parallel to each other. The first solar cell stack is optimized for absorption of incoming solar light in a first wavelength range and the second solar cell stack is optimized for absorption of incoming solar light in a second wavelength range, wherein the first and the second wavelength range do not or at most only partially overlap each other.

A voltage matched multijunction solar cell having first and second solar cell stacks that are electrically connected parallel to each other. The first solar cell stack is optimized for absorption of incoming solar light in a first wavelength range and the second solar cell stack is optimized for absorption of incoming solar light in a second wavelength range, wherein the first and the second wavelength range do not or at most only partially overlap each other.

A tandem photovoltaic device includes: a tunnel junction between an upper cell unit and a lower cell unit. The lower cell unit is a crystalline silicon cell. The tunnel junction includes: a carrier transport layer, a crystalline silicon layer, and an intermediate layer located between the carrier transport layer and the crystalline silicon layer. The carrier transport layer is a metal oxide layer. The intermediate layer includes a tunneling layer. The crystalline silicon layer has a doping concentration greater than or equal to 10.sup.17 cm.sup.−3. The carrier transport layer is in direct contact with a shadow surface of the upper cell unit. If the crystalline silicon layer is a p-type crystalline silicon layer, a first energy level is close to a second energy level. If the crystalline silicon layer is an n-type crystalline silicon layer, a third energy level is close to a fourth energy level.

A tandem photovoltaic device includes: a tunnel junction between an upper cell unit and a lower cell unit. The lower cell unit is a crystalline silicon cell. The tunnel junction includes: a carrier transport layer, a crystalline silicon layer, and an intermediate layer located between the carrier transport layer and the crystalline silicon layer. The carrier transport layer is a metal oxide layer. The intermediate layer includes a tunneling layer. The crystalline silicon layer has a doping concentration greater than or equal to 10.sup.17 cm.sup.−3. The carrier transport layer is in direct contact with a shadow surface of the upper cell unit. If the crystalline silicon layer is a p-type crystalline silicon layer, a first energy level is close to a second energy level. If the crystalline silicon layer is an n-type crystalline silicon layer, a third energy level is close to a fourth energy level.

This disclosure provides photovoltaic cells and substrates with three dimensional optical architectures and methods of manufacturing the same. In particular, the disclosure relates to a continuously formed photovoltaic substrate, and to systems, devices, methods and uses for such a product, including the collection of solar energy.