Disclosed is a novel compound represented by formula (1) below. In the formula, A represents an optionally substituted aromatic hydrocarbon ring or aromatic heterocyclic group, B represents a group including a chain of one to four pieces of one or more groups selected from groups represented by specific formulae (B-1) to (B-13) (such as —C═C— or —N═N—, specifically see the description), R1 to R3 each represent an optionally substituted hydrocarbon or hydrocarbonoxy group, at least one of R1 to R3 represents an optionally substituted hydrocarbonoxy group, R4 and R5 each represent an optionally substituted hydrocarbon group, R4 and R5 may be linked together to form a ring, and R4 and R5 may be each independently linked with A to form a ring ##STR00001##

The present invention is a solar cell comprising a gallium-doped silicon substrate having a p-n junction formed therein, wherein the silicon substrate is provided with a silicon thermal oxide film at least on the first main surface of main surfaces of the silicon substrate, the first main surface being a main surface having a p-type region, and the silicon substrate is further doped with boron. This provides a solar cell that can possess high conversion efficiency while suppressing the photo-degradation even though having a silicon thermal oxide film as a passivation film of the substrate surface, and a method for manufacturing such a solar cell.

Disclosed is a method for making interconnected solar cells, including: a) providing a continuous layer stack on a substrate, including a top electrode layer, a bottom electrode layer adjacent to the substrate, a photovoltaic active layer and a barrier layer adjacent to the bottom electrode layer between the top and bottom electrode layers; b) selectively removing the top electrode layer and the photo-voltaic layer for obtaining a first trench exposing the barrier layer using a first laser beam with a first wavelength; c) selectively removing the barrier layer and the bottom electrode layer within the first trench for obtaining a second trench exposing the substrate using a second laser beam with a second wavelength, d) filling the first trench and the second trench with electrical insulating member. The first wavelength of the first laser beam is larger than a wavelength corresponding with a bandgap energy of the photo-voltaic layer.

Disclosed is a method for making interconnected solar cells, including: a) providing a continuous layer stack on a substrate, including a top electrode layer, a bottom electrode layer adjacent to the substrate, a photovoltaic active layer and a barrier layer adjacent to the bottom electrode layer between the top and bottom electrode layers; b) selectively removing the top electrode layer and the photo-voltaic layer for obtaining a first trench exposing the barrier layer using a first laser beam with a first wavelength; c) selectively removing the barrier layer and the bottom electrode layer within the first trench for obtaining a second trench exposing the substrate using a second laser beam with a second wavelength, d) filling the first trench and the second trench with electrical insulating member. The first wavelength of the first laser beam is larger than a wavelength corresponding with a bandgap energy of the photo-voltaic layer.

A photodiode (112,200,400,500) includes a semiconductor substrate (210) having a first surface (211) and a second surface (212,412,512), and a light sensing junction (220) located adjacent to the first surface (211). The second surface (212,412, 512) is located opposite the first surface (211), and the second surface (212,412,512) includes a concave surface covering a recessed region (415,515) in the semiconductor substrate (210).

A photodiode (112,200,400,500) includes a semiconductor substrate (210) having a first surface (211) and a second surface (212,412,512), and a light sensing junction (220) located adjacent to the first surface (211). The second surface (212,412, 512) is located opposite the first surface (211), and the second surface (212,412,512) includes a concave surface covering a recessed region (415,515) in the semiconductor substrate (210).

A photodetector array includes a substrate, and an array of pixels over the substrate. Each pixel includes a set of diffraction gratings directly on a semiconductor photodetector. A pitch of the set of diffraction gratings associated with each pixel in the array of pixels are different to enable each pixel to detect a specific wavelength of light different than other pixels of the array of pixels. An air cavity may be provided in the substrate under the germanium photodetector to improve light absorption. A method of forming the photodetector array is also disclosed.

A photodetector array includes a substrate, and an array of pixels over the substrate. Each pixel includes a set of diffraction gratings directly on a semiconductor photodetector. A pitch of the set of diffraction gratings associated with each pixel in the array of pixels are different to enable each pixel to detect a specific wavelength of light different than other pixels of the array of pixels. An air cavity may be provided in the substrate under the germanium photodetector to improve light absorption. A method of forming the photodetector array is also disclosed.

A photoelectric conversion material dispersion liquid of an embodiment includes: perovskite crystal particles having a composition represented as ABX.sub.3, where A is a monovalent cation of an amine compound, B is a divalent cation of a metal element, and X is a monovalent anion of a halogen element, and having an average particle diameter of not less than 10 nm nor more than 10000 nm; and a dispersion medium which is composed of a poor solvent to the perovskite crystal particles, and in which the perovskite crystal particles are dispersed.

A photoelectric conversion material dispersion liquid of an embodiment includes: perovskite crystal particles having a composition represented as ABX.sub.3, where A is a monovalent cation of an amine compound, B is a divalent cation of a metal element, and X is a monovalent anion of a halogen element, and having an average particle diameter of not less than 10 nm nor more than 10000 nm; and a dispersion medium which is composed of a poor solvent to the perovskite crystal particles, and in which the perovskite crystal particles are dispersed.