The present disclosure relates to a heterojunction solar cell, a manufacturing method thereof and a photovoltaic module. The heterojunction solar cell includes a substrate of a first conductivity type, a tunnel layer located on a light-receiving surface of the substrate, and a doped polysilicon layer located on a top surface of the tunnel layer. The doped polysilicon layer has the first conductivity type.

The present invention relates to devices comprising metal halide perovskites and organic passivating agents. In particular, the invention relates to photovoltaic and optoelectronic devices comprising passivated metal halide perovskites. The device according to the invention comprises: (a) a metal halide perovskite; and (b) a passivating agent which is an organic compound; wherein molecules of the passivating agent are chemically bonded to anions or cations in the metal halide perovskite. The invention also provides a process for producing a photovoltaic device, which photovoltaic device comprises: (a) a metal halide perovskite; and (b) a passivating agent which is an organic compound; wherein molecules of the passivating agent are chemically bonded to anions or cations in the metal halide perovskite, wherein the process comprises treating a metal halide perovskite with a passivating agent, which passivating agent is an organic compound and is suitable for chemically bonding to anions or cations in the metal halide perovskite.

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.

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.

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 germanium single-crystal wafer comprises silicon with an atomic concentration of from 310.sup.14 atoms/cc to 1010.sup.18 atoms/cc, boron with an atomic concentration of from 110.sup.16 atoms/cc to 1010.sup.18 atoms/cc, and gallium with an atomic concentration of from 110.sup.16 atoms/cc to 1010.sup.19 atoms/cc. Further provided are a method for preparing the germanium single-crystal wafer, a method for preparing a germanium single-crystal ingot, and the use of the germanium single-crystal wafer for increasing the open-circuit voltage of a solar cell. The germanium single-crystal wafer has an improved electrical property in that it has a smaller difference in resistivity and carrier concentration.

A germanium single-crystal wafer comprises silicon with an atomic concentration of from 310.sup.14 atoms/cc to 1010.sup.18 atoms/cc, boron with an atomic concentration of from 110.sup.16 atoms/cc to 1010.sup.18 atoms/cc, and gallium with an atomic concentration of from 110.sup.16 atoms/cc to 1010.sup.19 atoms/cc. Further provided are a method for preparing the germanium single-crystal wafer, a method for preparing a germanium single-crystal ingot, and the use of the germanium single-crystal wafer for increasing the open-circuit voltage of a solar cell. The germanium single-crystal wafer has an improved electrical property in that it has a smaller difference in resistivity and carrier concentration.

A solar cell can include a silicon semiconductor substrate; an oxide layer on a first surface of the silicon semiconductor substrate; a polysilicon layer on the oxide layer; a diffusion region at a second surface of the silicon semiconductor substrate; a dielectric film on the polysilicon layer; a first electrode connected to the polysilicon layer through the dielectric film; a passivation film on the diffusion region; and a second electrode connected to the diffusion region through the passivation film.

A solar cell can include a silicon semiconductor substrate; an oxide layer on a first surface of the silicon semiconductor substrate; a polysilicon layer on the oxide layer; a diffusion region at a second surface of the silicon semiconductor substrate; a dielectric film on the polysilicon layer; a first electrode connected to the polysilicon layer through the dielectric film; a passivation film on the diffusion region; and a second electrode connected to the diffusion region through the passivation film.

A solar cell and a photovoltaic module. The solar cell includes substrate, tunnel oxide layer, doped conductive layer, intrinsic polycrystalline silicon layer, enhanced conductive portion, and first electrodes. The tunnel oxide layer covers the first surface of the substrate. The doped conductive layer covers one side of the tunnel oxide layer away from the substrate. The intrinsic polycrystalline silicon layer is formed on one side of the doped conductive layer away from the tunnel oxide layer. The enhanced conductive portion covers one side of the intrinsic polycrystalline silicon layer away from the doped conductive layer, and is at least partially connected to the doped conductive layer. First electrodes are formed on one side of the enhanced conductive portion away from the intrinsic polycrystalline silicon layer, and at least part of each first electrode is located in the enhanced conductive portion to be electrically connected to the doped conductive layer.