Abstract: A light concentrator of an embodiment includes: a first high refractive index layer, a first low refractive index layer, and a second high refractive index layer stacked in sequence, wherein a surface on the first low refractive index layer side of the first high refractive index layer has a periodic concavoconvex region.

Abstract: A photoelectric conversion device of an embodiment has a substrate, a bottom electrode comprising an electrode layer on the substrate and an intermediate interface layer, a light absorbing layer on the intermediate interface layer. The electrode layer comprises Mo or W. The intermediate interface layer is a compound thin film of a compound comprising Mo or W and at least one element X selected from the group consisting of S, Se, and Te. The intermediate interface layer has a crystal phase and an amorphous phase with which the crystal phase is covered.

Abstract: According to one embodiment, a multi-junction solar cell includes a first solar cell, a second solar cell, and an insulating layer. The first solar cell includes a first photoelectric conversion element. The second solar cell is connected in parallel with the first solar cell. The second solar cell includes multiple second photoelectric conversion elements connected in series. The insulating layer is provided between the first solar cell and the second solar cell. The second photoelectric conversion element includes a p-electrode and an n-electrode. The p-electrode is connected to a p+-region including a surface on a side opposite to a light incident surface. The n-electrode is connected to an n+-region including the surface on the side opposite to the light incident surface. The p-electrodes oppose each other or the n-electrodes oppose each other in a region where the multiple second photoelectric conversion elements are adjacent to each other.

Abstract: A photoelectric conversion device of an embodiment has a substrate, a bottom electrode on the substrate, a light absorbing layer on the bottom electrode, an n-type layer on the light absorbing layer, a transparent electrode on the n-type layer, and an oxide layer on the transparent electrode. nA and nB satisfy the relation 100/110?nB/nA?110/100. nA is the refractive index of the transparent electrode. nB is the refractive index of the oxide layer.

Abstract: A photoelectric conversion device of an embodiment has a bottom electrode, an intermediate layer on the bottom electrode, a p-type light absorbing layer on the intermediate layer, and an n-type layer on the p-type light absorbing layer. The bottom electrode is a first metal film or a semiconductor film. When the bottom electrode is a metal film, the intermediate layer comprises an oxide film or a sulfide film. When the bottom electrode is a semiconductor film, the intermediate layer comprises a second metal film and an oxide film or a sulfide film on the second metal film.

Abstract: A photoelectric conversion device of an embodiment has a bottom electrode, a light absorbing layer on the bottom electrode. The light absorbing layer comprises a thin film of a semiconductor comprising a group Ib element or elements, a group IIIb element or elements, and a group VIb element or elements and having a chalcopyrite structure. The light absorbing layer has an average crystal grain size of 1.5 ?m or more. The group IIIb element or elements include Ga, Al, or both of Ga and Al.

Abstract: An antenna device arranged around a printed circuit board is provided. The antenna device has an antenna element connected to a feeder circuit provided on the printed board. The antenna device has an isolating material provided between the antenna element and the substrate material. The isolating material is constituted by an insulating substrate material and a plurality of pieces of magnetic material provided on the substrate material. Adjacent ones of the pieces of the magnetic material are arranged separate from each other.

Abstract: A multi-junction solar cell of an embodiment includes a first solar cell including a first photoelectric conversion device, a second solar cell including a plurality of second photoelectric conversion devices connected in series and having a back contact, and an insulating layer between the first solar cell and the second solar cell. A device isolation region is provided between the second photoelectric conversion devices connected in series.

Abstract: A method for manufacturing a photoelectric conversion device of an embodiment includes forming, on a first electrode, a photoelectric conversion layer comprising at least one of a chalcopyrite compound, a stannite compound, and a kesterite compound. The forming of the photoelectric conversion layer includes forming a photoelectric conversion layer precursor comprising at least one compound semiconductor of a chalcopyrite compound, a stannite compound, and a kesterite compound on the first electrode. The forming of the photoelectric conversion layer includes immersing the precursor in a liquid including at least one of Group IIa and Group IIb elements at 0° C. to 60° C., after forming of the photoelectric conversion layer precursor. The compound semiconductor on a side of the first electrode is at least either amorphous or larger in average crystal grain size than the compound semiconductor on an opposite side of the first electrode.

Abstract: A solar cell of an embodiment has a first solar cell, a second solar cell, and an intermediate layer between the first and second solar cells. The first solar cell has a Si layer as a light absorbing layer. The second solar cell has as a light absorbing layer one of a group I-III-VI2 compound layer and a group I2-II-IV-VI4 compound layer. The intermediate layer has an n+-type Si sublayer and at least one selected from a p+-type Si sublayer, a metal compound sublayer, and a graphene sublayer. The metal compound sublayer is represented by MX where M denotes at least one type of element selected from Nb, Mo, Pd, Ta, W, and Pt and X denotes at least one type of element selected from S, Se, and Te.

Abstract: An aspect of one embodiment, there is provided a photoelectric conversion element, including a first electrode having optical transparency, a second electrode, and an optical absorption layer provided between the first electrode and the second electrode, the optical absorption layer having a compound semiconductor constituted with a chalcopyrite structure or a stannite structure, the compound semiconductor having a first element of a Group 11 element and a second element of a Group 16 element and comprising a p-type portion and an n-type portion provided between the p-type portion and the first electrode, the n-type portion and the p-type portion jointly having a homo junction, wherein the n-type portion comprises a dopant which has a formal charge Vb being not less than 1.60 and not more than 2.83.

Abstract: A light concentrator of an embodiment includes: a first high refractive index layer, a first low refractive index layer, and a second high refractive index layer stacked in sequence, wherein a surface on the first low refractive index layer side of the first high refractive index layer has a periodic concavoconvex region.

Abstract: A photoelectric conversion element of an embodiment includes: a p-type light absorbing layer having a chalcopyrite structure; an n-type semiconductor layer on the p-type light absorbing layer; an oxide layer on the n-type semiconductor layer; and a transparent electrode on the oxide layer.

Abstract: A photoelectric conversion element of an embodiment includes: a back electrode; a heterojunction-type light absorbing layer on the back electrode, containing Cu, selected from Al, In and Ga, and selected from Se and S, and having a chalcopyrite structure; a transparent electrode on the light absorbing layer, wherein aback electrode side-part of the light absorbing layer is of p-type, and a transparent electrode-side part of the light absorbing layer is of n-type, the light absorbing layer has a part with an average crystal grain size of 1,000 nm to 3,000 nm in the vicinity of the back electrode, and the light absorbing layer has apart with an average crystal grain size of at most 500 nm in the vicinity of the transparent electrode or the light absorbing layer has an amorphous part in the vicinity of the transparent electrode.

Abstract: A photoelectric conversion element includes a photoelectric conversion layer, a transparent electrode, an intermediate layer, and a window layer. The photoelectric conversion layer includes a homojunction of a p-type compound semiconductor layer and an n-type compound semiconductor layer. The p-type and n-type compound semiconductors include group I-III-VI2 compound or group I2-II-IV-VI4 compound. The intermediate layer is provided between the n-type compound semiconductor layer and the transparent electrode. The intermediate layer is 1 nm to 10 nm in thickness. The window layer is provided between the intermediate layer and the transparent electrode.

Abstract: A photoelectric conversion element of an embodiment includes: a light absorbing layer containing copper (Cu), at least one Group IIIb element selected from the group including aluminum (Al), indium (In) and gallium (Ga), and sulfur (S) or selenium (Se), and having a chalcopyrite structure; and a buffer layer formed from zinc (Zn) and oxygen (O) or sulfur (S), wherein the molar ratio represented by S/(S+O) of the buffer layer is equal to or greater than 0.7 and equal to or less than 1.0, and the crystal grain size is equal to or greater than 10 nm and equal to or less than 100 nm.

Abstract: A photoelectric conversion element of an embodiment includes a p-type light absorbing layer containing Cu, at least one or more Group IIIb elements selected from the group including Al, In and Ga, and at least one or more elements selected from the group including O, S, Se and Te; and an n-type semiconductor layer formed on the p-type light absorbing layer and represented by any one of Zn1-yMyO1-xSx, Zn1-y-zMgzMyO (wherein M represents at least one element selected from the group including B, Al, In and Ga), and GaP with a controlled carrier concentration, while x, y and z in the formulas Zn1-yMyO1-xSx and Zn1-y-zMgzMyO satisfy the following relations: 0.55?x?1.0, 0.001?y?0.05, and 0.002?y+z?1.0.

Abstract: A photoelectric conversion element of an embodiment includes: a light absorbing layer containing Cu, at least one Group IIIb element selected from the group including Al, In and Ga, and S or Se, and having a chalcopyrite structure; and a buffer layer formed from Zn and O or S, in which the ratio S/(S+O) in the area extending in the buffer layer up to 10 nm from the interface between the light absorbing layer and the buffer layer, is equal to or greater than 0.7 and equal to or less than 1.0.

Abstract: A compound thin film solar cell contains at least: includes a substrate; a back surface electrode provided on the substrate; an extraction electrode provided on the back surface electrode; a light absorbing layer provided on the back surface electrode; a buffer layer provided on the light absorbing layer; a transparent electrode layer provided on the buffer layer; an anti-reflective film provided on the transparent electrode layer; and an extraction electrode provided on the transparent electrode layer, wherein the light absorbing layer is formed from Cu(Al1-x-yGaxIny)(Te1-zOz)2 [provided that x and y are in the ranges defined by (Expression 1), with z=0; or x and y are in the ranges defined by (Expression 2), with 0.001?z?0.0625)], and the compound has a chalcopyrite type crystal structure. Eg=2.25?1.02x?1.29y (1.5?Eg?1.0)??(Expression 1) Eg=2.25?1.02x?1.29y (2.25?Eg?1.

Abstract: A compound thin film solar cell of an embodiment includes: as a light-absorbing layer a semiconductor thin film which contains Cu, an element A (A is at least one element selected from a group consisting of Al, In and Ga) and Te, and has a chalcopyrite crystal structure, wherein a buffer layer that forms an interface with the light-absorbing layer is a compound which contains at least one element selected from Cd, Zn and a group consisting of In and Ga and at least one element selected from a group consisting of S, Se and Te, and has any crystal structure of a sphalerite structure, a wurtzite structure and a defect spinel structure, and a lattice constant “a” of the buffer layer with the sphalerite structure or a lattice constant “a” of the buffer layer at the time of converting the wurtzite structure or the defect spinel structure to the sphalerite structure is not smaller than 0.59 nm and not larger than 0.62 nm.