Abstract: A light-receiving-surface bus electrode has a protrusion on an upper surface thereof in an intersection region where the bus electrode intersects with each of light-receiving-surface grid electrodes, the protrusion protruding from the upper surface and having a shape corresponding to a shape of each of the grid electrodes with the bus electrode and each of the grid electrodes overlapping. A light-receiving-surface-side lead wire has a flat upper surface opposite from a lower surface of the lead wire, the lower surface being an attachment surface to the bus electrode. The lead wire also has a recess in the lower surface, the recess being capable of accommodating the protrusion. A bottom surface of the recess and an upper portion of the protrusion are attached together with the protrusion accommodated in the recess, and the lower surface is attached to the upper surface of the bus electrode.

Abstract: A solar cell includes a first conductive type semiconductor substrate in which a through hole is formed, a second conductive type impurity diffusion layer provided on one-surface side of the semiconductor substrate, a light-receiving surface electrode provided to be electrically connected to the impurity diffusion layer, a lead-out electrode led out to the other-surface side of the semiconductor substrate via the through hole and provided to be electrically connected to the light-receiving surface electrode, and a back-surface electrode electrically connected to the semiconductor substrate on the other-surface side of the semiconductor substrate and electrically separated from the lead-out electrode. The lead-out electrode contains a metal member inside the through hole and is electrically connected to the light-receiving surface electrode.

Abstract: A solar cell includes: a semiconductor substrate of a first conductivity type that includes an impurity diffusion layer, in which an impurity element of a second conductivity type is diffused, on one surface side; a passivation film that is formed on the impurity diffusion layer and that is made of an oxide film of a material of the semiconductor substrate; an anti-reflective film that is made of a translucent material having a refractive index different from that of the oxide film and that is formed on the passivation film; a light-receiving-surface-side electrode that is electrically connected to the impurity diffusion layer and that is formed on one surface side of the semiconductor substrate; and a rear-surface-side electrode that is formed on another surface side of the semiconductor substrate.

Abstract: A scraper central portion in which a first contact surface has a trapezoidal shape with a lower base longer than an upper base, and scraper end portions that extend and are bent from respective lateral sides of a trapezoidal shape of the scraper central portion to a side of the first contact surface, and that include second contact surfaces that come in contact with the coating material. A lower base of the scraper central portion and lower sides of the scraper end portions are on the same plane. In a state where the first contact surface is vertical to the surface of the screen plate, the lower base of the scraper central portion and the lower sides of the scraper end portions come in contact with the coating material on the surface of the screen plate, and slide on the surface of the screen plate.

Abstract: A cleaning method of a silicon substrate includes a first step of etching a surface of a silicon substrate by a metal-ion-containing mixed aqueous solution of an oxidizing agent and hydrofluoric acid and of forming a porous layer on the surface of the silicon substrate, a second step of etching a pore of the porous layer by mixed acid mainly containing hydrofluoric acid and nitric acid and of forming texture on the surface of the silicon substrate, a third step of etching the surface of the silicon substrate on which the texture is formed with an alkaline chemical solution, and a fourth step of treating the silicon substrate etched by the alkaline chemical solution by ozone-containing water, of generating an air bubble within the pore formed in the silicon substrate, and of removing metal and organic impurities from within the pore.

Abstract: A solar cell includes a first conductive type semiconductor substrate in which a through hole is formed, a second conductive type impurity diffusion layer provided on one-surface side of the semiconductor substrate, a light-receiving surface electrode provided to be electrically connected to the impurity diffusion layer, a lead-out electrode led out to the other-surface side of the semiconductor substrate via the through hole and provided to be electrically connected to the light-receiving surface electrode, and a back-surface electrode electrically connected to the semiconductor substrate on the other-surface side of the semiconductor substrate and electrically separated from the lead-out electrode. The lead-out electrode contains a metal member inside the through hole and is electrically connected to the light-receiving surface electrode.

Abstract: A scraper central portion in which a first contact surface has a trapezoidal shape with a lower base longer than an upper base, and scraper end portions that extend and are bent from respective lateral sides of a trapezoidal shape of the scraper central portion to a side of the first contact surface, and that include second contact surfaces that come in contact with the coating material. A lower base of the scraper central portion and lower sides of the scraper end portions are on the same plane. In a state where the first contact surface is vertical to the surface of the screen plate, the lower base of the scraper central portion and the lower sides of the scraper end portions come in contact with the coating material on the surface of the screen plate, and slide on the surface of the screen plate.

Abstract: A cleaning method of a silicon substrate includes a first step of etching a surface of a silicon substrate by a metal-ion-containing mixed aqueous solution of an oxidizing agent and hydrofluoric acid and of forming a porous layer on the surface of the silicon substrate, a second step of etching a pore of the porous layer by mixed acid mainly containing hydrofluoric acid and nitric acid and of forming texture on the surface of the silicon substrate, a third step of etching the surface of the silicon substrate on which the texture is formed with an alkaline chemical solution, and a fourth step of treating the silicon substrate etched by the alkaline chemical solution by ozone-containing water, of generating an air bubble within the pore formed in the silicon substrate, and of removing metal and organic impurities from within the pore.

Abstract: A method includes: a first step of forming a passivation film on a first surface of a crystalline silicon substrate of a first conductive type; a second step of diffusing an element of a second conductive type into a second surface of the crystalline silicon substrate by thermal diffusion to form a diffusion layer, whereby a pn junction is formed; a third step of forming an antireflection film on the diffusion layer; a fourth step of disposing a first electrode paste on the second surface of the crystalline silicon substrate; a fifth step of disposing a second electrode paste on the passivation film; and a sixth step of firing the first electrode paste and the second electrode paste to form electrodes.

Abstract: A wet-etching jig, which is a wet-etching jig that holds a plate workpiece when the workpiece is wet-etched, includes: a holding unit configured to include a suction unit in which a suction port is formed for absorbing the air and a first close contact unit that is provided to surround the suction unit and that can closely contact a first surface of the workpiece to surround a predetermined region of the first surface; an exhaust path that communicates with the suction port; and a check valve that is provided in the exhaust path to intercept a flow of the air in a direction toward the suction unit and to permit a flow of the air from the suction unit.

Abstract: Connection tabs include: a first connection tab 72 that is electrically connected to a connection electrode 62 on a rear side of the first solar battery cell 11 and extends to a rear side of the second solar battery cell 21; and a second connection tab 71 that is electrically connected to a connection electrode 52 on a light-receiving side of the second solar battery cell 21 and has a bent folded-back portion which extends to the rear side of the second solar battery cell 21 near the first solar battery cell 11 from the second solar battery cell. The first connection tab 71 and the second connection tab 72 are connected in a connection region that is within an overlapping region in which the first connection tab 72 and the second connection tab 21 overlap in a rear side of the second solar battery cell 21, and that is narrower than the overlapping region in the first direction.

Abstract: Provided are a wire electric discharge machining method for poorly conductive materials, such as solar cell silicon, and a semiconductor wafer manufacturing method and a solar battery cell manufacturing method based on the wire electric discharge machining method. Electrical discharge machining of a high volume resistivity, hard and brittle materials, having a volume resistivity that is equal to or higher than 0.5 ?·cm and equal to or lower than 5 ?·cm is performed by applying a pulse voltage having a pulse width that is equal to or higher than 1 ?sec and equal to or lower than 4 ?sec and having a peak current at the time of machining a wire electrode that is equal to or higher than 10A and equal to or lower than 50A to a wire electrode and generating a discharge pulse between the wire electrode and a subject to be machined.

Abstract: A method of manufacturing a solar cell having a texture on a surface of a silicon substrate includes first forming a porous layer on the surface of the silicon substrate by dipping the silicon substrate into a mixed aqueous solution of oxidizing reagent containing metal ions and hydrofluoric acid. Second, a texture is formed by etching the surface of the silicon substrate after the porous layer is formed, by dipping the silicon substrate into a mixed acid mainly containing hydrofluoric acid and nitric acid.

Abstract: A method includes: a first step of forming a passivation film on a first surface of a crystalline silicon substrate of a first conductive type; a second step of diffusing an element of a second conductive type into a second surface of the crystalline silicon substrate by thermal diffusion to form a diffusion layer, whereby a pn junction is formed; a third step of forming an antireflection film on the diffusion layer; a fourth step of disposing a first electrode paste on the second surface of the crystalline silicon substrate; a fifth step of disposing a second electrode paste on the passivation film; and a sixth step of firing the first electrode paste and the second electrode paste to form electrodes.

Abstract: A method of manufacturing a solar cell includes forming a diffusion layer on a crystal-type silicon substrate. The diffusion layer has a conductivity opposite to that of the substrate. Furthermore, the method includes etching and removing a part of the diffusion layer by using sodium silicate, and forming a first electrode that makes an electric contact with the diffusion layer and forming a second electrode that makes an electric contact with the substrate.

Abstract: A method of manufacturing a solar cell having a texture on a surface of a silicon substrate includes first forming a porous layer on the surface of the silicon substrate by dipping the silicon substrate into a mixed aqueous solution of oxidizing reagent containing metal ions and hydrofluoric acid. Second, a texture is formed by etching the surface of the silicon substrate after the porous layer is formed, by dipping the silicon substrate into a mixed acid mainly containing hydrofluoric acid and nitric acid.

Abstract: Provided are a wire electric discharge machining method for poorly conductive materials, such as solar cell silicon, and a semiconductor wafer manufacturing method and a solar battery cell manufacturing method based on the wire electric discharge machining method. Electrical discharge machining of a high volume resistivity, hard and brittle materials, having a volume resistivity that is equal to or higher than 0.5 ?·cm and equal to or lower than 5 ?·cm is performed by applying a pulse voltage having a pulse width that is equal to or higher than 1 ?sec and equal to or lower than 4 ?sec and having a peak current at the time of machining a wire electrode that is equal to or higher than 10A and equal to or lower than 50A to a wire electrode and generating a discharge pulse between the wire electrode and a subject to be machined.

Abstract: A method of manufacturing a solar cell includes forming a diffusion layer on a crystal-type silicon substrate. The diffusion layer has a conductivity opposite to that of the substrate. Furthermore, the method includes etching and removing a part of the diffusion layer by using sodium silicate, and forming a first electrode that makes an electric contact with the diffusion layer and forming a second electrode that makes an electric contact with the substrate.

Abstract: In preparing a solar cell, minute projections and recesses are uniformly formed in a surface of a single crystal silicon substrate or a polycrystal silicon substrate by dipping in an etching liquid composed of a mixed acid which is composed mainly of a hydrofluoride acid, a nitric acid and a phosphoric acid in addition to a surface active agent. A solar cell having a substrate in which spherical projections and recesses are formed in a surface of it to which light is incident; an apparatus for producing efficiently a solar cell by realizing the above-mentioned process, and a wet etching apparatus to effect stably the above-mentioned process to thereby maintaining a concentration of a nitric acid to be constant, are provided.

Abstract: In preparing a solar cell, minute projections and recesses are uniformly formed in a surface of a single crystal silicon substrate or a polycrystal silicon substrate by dipping the substrate in an etching liquid of a mixed acid including a hydrofluoride acid, a nitric acid and an adjusting agent containing at least a phosphoric acid or a water-soluble carboxylic acid having a higher molecular weight than acetic acid for adjusting the etching rate of the etching liquid. A solar cell having a substrate in which spherical projections and recesses are formed in a surface thereof to which light is incident; an apparatus for producing a solar cell, and a wet etching apparatus to maintain a constant concentration of a nitric acid, are provided.