Abstract: A negative electrode active material including silicon monoxide particles, wherein the silicon monoxide particles satisfy that, in volumetric basis distribution measured with a laser-diffraction method particle size distribution measurement device, an accumulative 0.1%-particle-size D0.1 satisfies 1.2 ?m?D0.1?3.0 ?m, an accumulative 10%-particle-size D10 satisfies 3.5 ?m?D10?7.0 ?m, an accumulative 50%-particle-size D50 satisfies 6.0 ?m?D50?15.0 ?m, and an accumulative 99.9%-particle-size D99.9 satisfies 25.0 ?m?D99.9?50.0 ?m, and the silicon monoxide particles satisfy that a BET specific surface area Sm satisfies 1.0 m2/g?Sm?3.5 m2/g. The negative electrode active material can improve cycle characteristics when used as the negative electrode active material for a negative electrode of a secondary battery.

Abstract: A negative electrode active material including silicon monoxide particles coated with a carbon coating and doped with lithium, wherein the silicon monoxide particles satisfy that, in volumetric basis distribution measured with a laser-diffraction method particle size distribution measurement device, an integrated value of a relative amount of particles having a particle size of 1 ?m or less is 1% or less, an integrated value of a relative amount of particles having a particle size of 5 ?m or less is 20% or less, and an accumulative 50%-particle-size D50 satisfies 6.0 ?m?D50?15.0 ?m. This provides a negative electrode active material that can improve cycle characteristics while keeping high first efficiency when used as the negative electrode active material for a negative electrode of a secondary battery.

Abstract: A method for screen printing, including: by using a screen printing apparatus provided with a screen printing plate having an opening part corresponding to a printing pattern, a scraper, and a squeegee, filling a paste supplied on an upper surface of the screen printing plate into the opening part of the screen printing plate by the scraper; and, after that, pushing out the paste to a predetermined position of an object to be printed from the opening part of the screen printing plate by the squeegee to screen-print the paste corresponding to the printing pattern on the object to be printed, wherein the humidity in the screen printing apparatus is adjusted during the screen printing. As a result, by controlling an amount of moisture in the paste on the screen printing plate, a screen printing method is capable of improving the printing property of the paste.

Abstract: A method for screen printing, including: by using a screen printing apparatus provided with a screen printing plate having an opening part corresponding to a printing pattern, a scraper, and a squeegee, filling a paste supplied on an upper surface of the screen printing plate into the opening part of the screen printing plate by the scraper; and, after that, pushing out the paste to a predetermined position of an object to be printed from the opening part of the screen printing plate by the squeegee to screen-print the paste corresponding to the printing pattern on the object to be printed, wherein the humidity in the screen printing apparatus is adjusted during the screen printing. As a result, by controlling an amount of moisture in the paste on the screen printing plate, a screen printing method is capable of improving the printing property of the paste.

Abstract: A solar cell wherein: an emitter layer is formed on a light-receiving-surface side of a crystalline silicon substrate, with a dopant of the opposite conductivity type from the silicon substrate added to said emitter layer; a passivation film is formed on the surface of the silicon substrate; and an extraction electrode and a collector electrode are formed. Said extraction electrode extracts photogenerated charge from the silicon substrate, and said collector electrode contacts the extraction electrode at least partially and collects the charge collected at the extraction electrode. The extraction electrode contains a first electrode that consists of a sintered conductive paste containing a dopant that makes silicon conductive. Said first electrode, at least, is formed so as to pass through the abovementioned passivation layer. The collection electrode contains a second electrode that has a higher conductivity than the aforementioned first electrode.

Abstract: A solar cell wherein: an emitter layer is formed on a light-receiving-surface side of a crystalline silicon substrate, with a dopant of the opposite conductivity type from the silicon substrate added to said emitter layer; a passivation film is formed on the surface of the silicon substrate; and an extraction electrode and a collector electrode are formed. Said extraction electrode extracts photogenerated charge from the silicon substrate, and said collector electrode contacts the extraction electrode at least partially and collects the charge collected at the extraction electrode. The extraction electrode contains a first electrode that consists of a sintered conductive paste containing a dopant that makes silicon conductive. Said first electrode, at least, is formed so as to pass through the abovementioned passivation layer. The collection electrode contains a second electrode that has a higher conductivity than the aforementioned first electrode.

Abstract: A coating fluid comprising a boron compound, an organic binder, a silicon compound, an alumina precursor, and water and/or an organic solvent is used to diffuse boron into a silicon substrate to form a p-type diffusion layer. The coating fluid is spin coated onto the substrate to form a uniform coating having a sufficient amount of impurity whereupon a p-type diffusion layer having in-plane uniformity is formed.

Abstract: Disclosed is a solar cell having a silicon monocrystal substrate surface with a textured structure and, near the surface of said substrate, a damage layer reflecting the slice processing history from the time of manufacture of the silicon monocrystal substrate. The damage layer near the surface of the silicon monocrystal substrate is derived from the slice processing history at the time of manufacture of the substrate and functions as a gettering site, contributing to a longer lifetime of the substrate minority carriers. Thanks to this effect, the solar cell characteristics are dramatically increased. Further, new damage need be inflicted, and no additional work is required because damage from the slicing is used.

Abstract: Disclosed in a method that is for producing a solar cell and that is characterized by performing an annealing step on a semiconductor substrate before an electrode-forming step. By means of performing annealing in the above manner, it is possible to improve the electrical characteristics of the solar cell without negatively impacting reliability or outward appearance. As a result, the method can be widely used in methods for producing solar cells having high reliability and electrical characteristics.

Abstract: Disclosed is a solar cell having a silicon monocrystal substrate surface with a textured structure and, near the surface of said substrate, a damage layer reflecting the slice processing history from the time of manufacture of the silicon monocrystal substrate. The damage layer near the surface of the silicon monocrystal substrate is derived from the slice processing history at the time of manufacture of the substrate and functions as a gettering site, contributing to a longer lifetime of the substrate minority carriers. Thanks to this effect, the solar cell characteristics are dramatically increased. Further, new damage need be inflicted, and no additional work is required because damage from the slicing is used.

Abstract: A solar cell has: an emitter layer formed on a light-receiving-surface side of a crystalline silicon substrate, with a dopant of the opposite conductivity type from the silicon substrate added to the emitter layer, a passivation film formed on the surface of the silicon substrate, an extraction electrode and a collector electrode. The extraction electrode extracts photogenerated charge from the silicon substrate and the collector electrode collects the charge collected at the extraction electrode. The extraction electrode contains a first electrode that consists of a sintered conductive paste. The first electrode, at least, is formed so as to pass through the passivation layer. The collection electrode contains a second electrode that has a higher conductivity than the first electrode. This solar cell reduces contact-resistance losses between the silicon and the electrodes, resistance losses due to electrode resistance, and optical and electrical losses in the emitter layer.

Abstract: Disclosed in a method that is for producing a solar cell and that is characterized by performing an annealing step on a semiconductor substrate before an electrode-forming step. By means of performing annealing in the above manner, it is possible to improve the electrical characteristics of the solar cell without negatively impacting reliability or outward appearance. As a result, the method can be widely used in methods for producing solar cells having high reliability and electrical characteristics.

Abstract: Disclosed is a phosphorus paste for diffusion that is used in continuous printing of a phosphorus paste for diffusion on a substrate by screen printing. The phosphorus paste for diffusion does not undergo a significant influence of ambient humidity on viscosity and has no possibility of thickening even after a large number of times of continuous printing. The phosphorus paste for diffusion is coated on a substrate by screen printing for diffusion layer formation on the substrate. The phosphorus paste for diffusion includes a doping agent containing phosphorus as a dopant for the diffusion layer, a thixotropic agent containing an organic binder and a solid matter, and an organic solvent. The doping agent is an organic phosphorus compound.

Abstract: Disclosed is a phosphorus paste for diffusion that is used in continuous printing of a phosphorus paste for diffusion on a substrate by screen printing. The phosphorus paste for diffusion does not undergo a significant influence of ambient humidity on viscosity and has no possibility of thickening even after a large number of times of continuous printing. The phosphorus paste for diffusion is coated on a substrate by screen printing for diffusion layer formation on the substrate. The phosphorus paste for diffusion includes a doping agent containing phosphorus as a dopant for the diffusion layer, a thixotropic agent containing an organic binder and a solid matter, and an organic solvent. The doping agent is an organic phosphorus compound.