Abstract: A compound solar cell having a higher conversion efficiency and a method for producing the compound solar cell at lower costs are provided. The compound solar cell includes a CIGS light absorbing layer, a buffer layer and a front side electrode layer provided on a substrate. An interface layer made of a mixed crystal compound having a composition represented by the following general formula is provided between the CIGS light absorbing layer and the buffer layer: Zn(Ox,S1-x) . . . (1), wherein X is 0.9<X?1.

Abstract: In order to provide a CIGS compound solar cell with a high conversion efficiency, a CIGS compound solar cell including a rear electrode layer, a CIGS light absorbing layer, a buffer layer, and a transparent electrode layer in this order over a substrate is configured such that the buffer layer comprises a mixed crystal of a Group IIa metal and zinc oxide, and characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (1): 0.5?A/(A+B+C)<1??(1) (where none of A, B, C are 0) A: peak intensity at plane (002) B: peak intensity at plane (100) C: peak intensity at plane (101).

Abstract: The present invention provides a CIGS film substantially free from oxidation of a front surface thereof and a CIGS solar cell employing the CIGS film and substantially free from reduction and variation in conversion efficiency. The CIGS film, which is used as a light absorbing layer for the CIGS solar cell, includes: a first region having a Ga/(In+Ga) ratio progressively reduced along its thickness toward a predetermined first thickness position from a back surface of the CIGS film; a second region having a Ga/(In+Ga) ratio progressively increased along its thickness toward a predetermined second thickness position from the first region; and a third region provided on the second region and having a Ga/(In+Ga) ratio progressively reduced along its thickness toward the front surface of the CIGS film.

Abstract: A CIGS type compound solar cell excellent in both productivity and conversion efficiency is provided. The CIGS type solar cell includes a CIGS light absorbing layer, a buffer layer and a transparent electrode layer provided in this order on a substrate. The buffer layer is made of a mixed crystal compound containing ZnO, MgO and ZnS being present at specific ranges respectively.

Abstract: The present invention provides a CIGS film production method which ensures that a CIGS film excellent in conversion efficiency can be produced at lower costs with higher reproducibility, and a CIGS solar cell production method using the CIGS film production method. The CIGS film production method includes: a stacking step of stacking an (A) layer containing indium, gallium and selenium and a (B) layer containing copper and selenium in this order in a solid phase over a substrate while heating at a temperature of higher than 250° C. and not higher than 400° C.; and a heating step of further heating the resulting stack of the (A) layer and the (B) layer to melt a compound of copper and selenium in the (B) layer into a liquid phase, whereby copper is diffused from the (B) layer into the (A) layer to cause crystal growth to provide a CIGS film.

Abstract: A CIGS type compound solar cell excellent in both productivity and conversion efficiency is provided. The CIGS type solar cell includes a CIGS light absorbing layer, a buffer layer and a transparent electrode layer provided in this order on a substrate. The buffer layer is made of a mixed crystal compound containing ZnO, MgO and ZnS being present at specific ranges respectively.

Abstract: The CIGS film production method includes: a stacking step of stacking a layer (A) containing indium, gallium and selenium and a layer (B) containing copper and selenium, in this order in a solid phase over a substrate; and a heating step of heating the resulting stack of the layer (A) and the layer (B) to melt the layer (B) into a liquid phase, whereby copper is diffused from the layer (B) into the layer (A) to cause crystal growth; wherein the layer (A) is formed by repeatedly stacking a gallium selenide film (Y) and an indium selenide film (X) in this order and reducing a thickness ratio (Y/X) between the gallium selenide film (Y) and the indium selenide film (X) as the stacking is repeated.

Abstract: The present invention provides a CIGS film substantially free from oxidation of a front surface thereof and a CIGS solar cell employing the CIGS film and substantially free from reduction and variation in conversion efficiency. The CIGS film, which is used as a light absorbing layer for the CIGS solar cell, includes: a first region having a Ga/(In+Ga) ratio progressively reduced along its thickness toward a predetermined first thickness position from a back surface of the CIGS film; a second region having a Ga/(In+Ga) ratio progressively increased along its thickness toward a predetermined second thickness position from the first region; and a third region provided on the second region and having a Ga/(In+Ga) ratio progressively reduced along its thickness toward the front surface of the CIGS film.

Abstract: A CIGS film production method capable of suppressing oxidation of a front surface of a CIGS film, and a CIGS solar cell production method using the CIGS film production method includes the steps of: forming a first region having a Ga/(In+Ga) ratio progressively reduced as the thickness of the first region increases to a predetermined first thickness position from a back surface of the CIGS film; forming a second region having a Ga/(In+Ga) ratio progressively increased as the thickness of the second region increases to a predetermined second thickness position from the first region; and forming a third region on the second region by vapor-depositing Se and In, the third region having a Ga/(In+Ga) ratio progressively reduced toward a front surface of the CIGS film.

Abstract: In order to provide a method that can manufacture a compound solar cell with a high conversion efficiency at low cost, a buffer layer is formed by a sputtering method with the use of a high-frequency RF power source or a high-frequency RF power source and a direct-current (DC) power source in combination, while two cathode targets for sputtering are arranged to be opposed to each other on both sides of an imaginary central axis assumed to extend perpendicularly from a surface of a substrate over with a CIGS light absorbing layer is stacked.

Abstract: A compound solar cell having a higher conversion efficiency and a method for producing the compound solar cell at lower costs are provided. The compound solar cell includes a CIGS light absorbing layer, a buffer layer and a front side electrode layer provided on a substrate. An interface layer made of a mixed crystal compound having a composition represented by the following general formula is provided between the CIGS light absorbing layer and the buffer layer: Zn(Ox,S1-x) . . . (1), wherein X is 0.9<X?1.

Abstract: A CIGS film production method is provided which ensures that a CIGS film having a higher conversion efficiency can be produced at lower costs at higher reproducibility even for production of a large-area device. A CIGS solar cell production method is also provided for producing a CIGS solar cell including the CIGS film. The CIGS film production method includes: a stacking step of stacking a layer (A) containing indium, gallium and selenium and a layer (B) containing copper and selenium in a solid phase in this order over a substrate; and a heating step of heating a stacked structure including the layer (A) and the layer (B) to melt a compound of copper and selenium of the layer (B) into a liquid phase to thereby diffuse copper from the layer (B) into the layer (A) to permit crystal growth to provide a CIGS film.

Abstract: In order to provide a CIGS compound solar cell with a high conversion efficiency, a CIGS compound solar cell including a rear electrode layer, a CIGS light absorbing layer, a buffer layer, and a transparent electrode layer in this order over a substrate is configured such that the buffer layer comprises a mixed crystal of a Group IIa metal and zinc oxide, and characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (1): 0.5?A/(A+B+C)<1 ??(1) (where none of A, B, C are 0) A: peak intensity at plane (002) B: peak intensity at plane (100) C: peak intensity at plane (101).

Abstract: A CIGS film production method is provided which ensures that a CIGS film having a higher conversion efficiency can be produced at lower costs at higher reproducibility even for production of a large-area device. A CIGS solar cell production method is also provided for producing a CIGS solar cell including the CIGS film. The CIGS film production method includes: a stacking step of stacking a layer (A) containing indium, gallium and selenium and a layer (B) containing copper and selenium in a solid phase in this order over a substrate; and a heating step of heating a stacked structure including the layer (A) and the layer (B) to melt a compound of copper and selenium of the layer (B) into a liquid phase to thereby diffuse copper from the layer (B) into the layer (A) to permit crystal growth to provide a CIGS film.

Abstract: A method for producing a solar battery cell which hardly causes an electric short circuit at the cut end surface of a solar battery element is provided. A method for producing a solar battery cell in which a solar battery cell is obtained from an elongated solar battery element including an elongated flexible base material, a first electrode layer, a light absorbing layer, and a second electrode layer in this order, and the method includes a partial removal step of forming one or more partial removal portion each extending like a belt at a plurality of parts in the surface of the solar battery element by partially removing layers of the second electrode layer through to the light absorbing layer or the second electrode layer through to the first electrode layer, and a cutting step of cutting the solar battery element at the partial removal portion.