A photovoltaic device includes: a silicon substrate having a front surface having a texture; and an amorphous silicon layer having an uneven surface corresponding to the texture, wherein the amorphous silicon layer is amorphous in peak portions and slope portions extending between the peak portions and valley portions of the uneven surface, and has crystalline regions which grow, in a pillar manner, approximately perpendicularly from a substrate surface of the silicon substrate in the valley portions, the crystalline regions being discretely present along upper ends of the valley portions, the upper ends being opposite lower ends of the valley portions, the lower ends being in contact with the silicon substrate, wherein coverage of the crystalline regions in the valley portions is higher than coverage of amorphous regions in the valley portions.

A solar cell includes: a semiconductor substrate formed of n-type crystalline silicon; a first stack formed of amorphous silicon in a first region on a first principle surface of the semiconductor substrate; a second stack formed of amorphous silicon in a second region different from the first region on the first principle surface; and a third stack formed of amorphous silicon on a second principle surface of the semiconductor substrate opposite from the first principle surface. The second stack has an oxygen concentration that is higher than that of the first stack.

A solar cell of an embodiment includes: a substrate; an n-electrode; an n-type layer; a p-type light absorption layer which is a semiconductor of a Cu-based oxide; and a p-electrode. The n-electrode is disposed between the substrate and the n-type layer. The n-type layer is disposed between the n-electrode and the p-type light absorption layer. The p-type light absorption layer is disposed between the n-type layer and the p-electrode. The n-type layer is disposed closer to a light incident side than the p-type light absorption layer. The substrate is a single substrate included in the solar cell.

Contacts for solar cells and other optoelectronic devices are provided. Embodiments described herein take advantage of the surface Fermi level pinning effect to build an electrical field inside of a semiconductor to extract or inject carriers for solar cells, photodetectors, and light-emitting device applications. For example, n-type or p-type two-dimensional (2D) materials can be used in contact with an n-type semiconductor to form a “p-region” so that a p-n junction, or an i-n or n-n+ junction can be constructed. Similarly, n-type or p-type 2D materials can be used in contact with a p-type semiconductor to form an “n-region” so that an n-p junction, or an i-p or p-p+ junction can be constructed. These structures can provide sufficiently high electrical field inside the semiconductor to extract photogenerated carriers in solar cells and photodetectors or inject minority carriers for light-emitting devices.

Techniques for enhancing the absorption of photons in semiconductors with the use of microstructures are described. The microstructures, such as pillars and/or holes, effectively increase the effective absorption length resulting in a greater absorption of the photons. Using microstructures for absorption enhancement for silicon photodiodes and silicon avalanche photodiodes can result in bandwidths in excess of 10 Gb/s at photons with wavelengths of 850 nm, and with quantum efficiencies of approximately 90% or more.

A laser-assisted microfluidics manufacturing process has been developed for the fabrication of additively manufactured structures. Roll-to-roll manufacturing is enhanced by the use of a laser-assisted electrospray printhead positioned above the flexible substrate. The laser electrospray printhead sprays microdroplets containing nanoparticles onto the substrate to form both thin-film and structural layers. As the substrate moves, the nanoparticles are sintered using a laser beam directed by the laser electrospray printhead onto the substrate.

There is provided a multi-junction photovoltaic device comprising a first sub-cell disposed over a second sub-cell, the first sub-cell comprising a photoactive region comprising a layer of perovskite material and the second sub-cell comprising a silicon heterojunction (SHJ).

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 photoelectric conversion module (10) comprises a photoelectric conversion cell (12) and a grid electrode (31) provided in the photoelectric conversion cell (12) on a substrate. The photoelectric conversion cell (12) includes a first electrode layer (22), a second electrode layer (24), a photoelectric conversion layer (26) between the first electrode layer (22) and the second electrode layer (24). The second electrode layer (24) is formed of a transparent electrode layer located on opposite side of the photoelectric conversion layer (26) to the substrate (20). The grid electrode (31) is provided between the photoelectric conversion layer (26) and the transparent electrode layer.

Tandem solar cell configurations are provided where at least one of the cells is a metal chalcogenide cell. A four-terminal tandem solar cell configuration has two electrically independent solar cells stacked on each other. A two-terminal solar cell configuration has two electrically coupled solar cells (same current through both cells) stacked on each other. Carrier selective contacts can be used to make contact to the metal chalcogenide cell (s) to alleviate the troublesome Fermi level pinning issue. Carrier-selective contacts can also remove the need to provide doping of the metal chalcogenide. Doping of the metal chalcogenide can be provided by charge transfer. These two ideas can be practiced independently or together in any combination.