A photoelectric conversion device includes a photoelectric conversion element formed of a polar material and including no p-n junction, and first and second electrodes provided on the photoelectric conversion element and arranged at an interval. Space-inversion symmetry of a structure of the photoelectric conversion element is broken. The first and second electrodes are each formed of a metal material that generates no substantial potential barrier preventing majority carriers for the photoelectric conversion element from moving from the electrode to the photoelectric conversion element. Light incidence on the photoelectric conversion element without voltage application between the first and second electrodes causes electromotive force to be generated between first and second electrodes, and enables electric current to be continuously taken out from the first and second electrodes.

A photoelectric conversion device includes a photoelectric conversion element formed of a polar material and including no p-n junction, and first and second electrodes provided on the photoelectric conversion element and arranged at an interval. Space-inversion symmetry of a structure of the photoelectric conversion element is broken. The first and second electrodes are each formed of a metal material that generates no substantial potential barrier preventing majority carriers for the photoelectric conversion element from moving from the electrode to the photoelectric conversion element. Light incidence on the photoelectric conversion element without voltage application between the first and second electrodes causes electromotive force to be generated between first and second electrodes, and enables electric current to be continuously taken out from the first and second electrodes.

The present invention is directed to photovoltaic and photogalvanic devices and methods of generating electrical energy and power or detecting light therefrom, based on a novel nano-enhanced bulk photovoltaic effect using non-centrosymmetric crystals, including ferroelectric and piezoelectric materials, where the non-centrosymmetry is the equilibrium state or it is static or dynamically induced. In certain embodiments, the device comprises a layer of non-centrosymmetric crystalline materials, and a plurality of electrodes disposed in an array upon or penetrating into at least one surface of the crystalline material, the electrodes being optimally spaced to capture the ballistic carriers generated upon irradiation of the crystalline material.

The present invention is directed to photovoltaic and photogalvanic devices and methods of generating electrical energy and power or detecting light therefrom, based on a novel nano-enhanced bulk photovoltaic effect using non-centrosymmetric crystals, including ferroelectric and piezoelectric materials, where the non-centrosymmetry is the equilibrium state or it is static or dynamically induced. In certain embodiments, the device comprises a layer of non-centrosymmetric crystalline materials, and a plurality of electrodes disposed in an array upon or penetrating into at least one surface of the crystalline material, the electrodes being optimally spaced to capture the ballistic carriers generated upon irradiation of the crystalline material.

A method of fabricating a solar cell is disclosed. The method can include forming a dielectric region on a surface of a solar cell structure and forming a metal layer on the dielectric layer. The method can also include configuring a laser beam with a particular shape and directing the laser beam with the particular shape on the metal layer, where the particular shape allows a contact to be formed between the metal layer and the solar cell structure.

A method of fabricating a solar cell is disclosed. The method can include forming a dielectric region on a surface of a solar cell structure and forming a metal layer on the dielectric layer. The method can also include configuring a laser beam with a particular shape and directing the laser beam with the particular shape on the metal layer, where the particular shape allows a contact to be formed between the metal layer and the solar cell structure.

A solar cell, and methods of fabricating said solar cell, are disclosed. The solar cell can include a first emitter region over a substrate, the first emitter region having a perimeter around a portion of the substrate. A first conductive contact is electrically coupled to the first emitter region at a location outside of the perimeter of the first emitter region.

In one embodiment, a solar cell has base and emitter diffusion regions formed on the back side. The emitter diffusion region is configured to collect minority charge carriers in the solar cell, while the base diffusion region is configured to collect majority charge carriers. The emitter diffusion region may be a continuous region separating the base diffusion regions. Each of the base diffusion regions may have a reduced area to decrease minority charge carrier recombination losses without substantially increasing series resistance losses due to lateral flow of majority charge carriers. Each of the base diffusion regions may have a dot shape, for example.

In one embodiment, a solar cell has base and emitter diffusion regions formed on the back side. The emitter diffusion region is configured to collect minority charge carriers in the solar cell, while the base diffusion region is configured to collect majority charge carriers. The emitter diffusion region may be a continuous region separating the base diffusion regions. Each of the base diffusion regions may have a reduced area to decrease minority charge carrier recombination losses without substantially increasing series resistance losses due to lateral flow of majority charge carriers. Each of the base diffusion regions may have a dot shape, for example.

A multijunction solar cell includes a base substrate comprising a Group IV semiconductor and a dopant of a first carrier type. A patterned emitter is formed at a first surface of the base substrate. The patterned emitter comprises a plurality of well regions doped with a dopant of a second carrier type in the Group IV semiconductor. The base substrate including the patterned emitter form a first solar subcell. The multijunction solar cell further comprises an upper structure comprising one or more additional solar subcells over the first solar subcell. Methods of making a multijunction solar cell are also described.