Abstract: A method of forming a nanometer-scale prominence and depression structure on a zinc oxide thin film in a wet-etching method, and the method includes the steps of: preparing a substrate; forming a nano structure having a height and a width of a nanometer range; forming the zinc oxide thin film on the substrate on which the nano structure is formed; and wet-etching the zinc oxide thin film, in which in the wet-etching step, zinc oxide having relatively low physical compactness is preferentially etched since the zinc oxide is positioned on the nano structure, and thus the prominence and depression structure is formed around the nano structure by the etching. The method is effective in that a thin film can be uniformly formed on the prominence and depression structure, and an electrolyte or an organic material may uniformly penetrate between the prominence and depression structure.

Abstract: A method of fabricating an Ag—(Cu—)In—Ga—Se (A(C)IGS) based thin film using Se—Ag2Se core-shell nanoparticles, an A(C)IGS based thin film fabricated by the method, and a tandem solar cell having the A(C)IGS thin film are disclosed. More particularly, a method of fabricating a densified Ag—(Cu—)In—Ga—Se (A(C)IGS) based thin film by non-vacuum coating a substrate with a slurry containing Se—Ag2Se core-shell nanoparticles, an A(C)IGS based thin film fabricated by the method, and a tandem solar cell including the A(C)IGS based thin film are disclosed. According to the present invention, an A(C)IGS based thin film including Ag is manufactured by applying Se—Ag2Se core-shell nanoparticles in a process of manufacturing a (C)IGS thin film, thereby providing an A(C)IGS based thin film having a wide band gap.

Abstract: Disclosed is an ultra-thin HIT solar cell, including: an n- or p-type crystalline silicon substrate; an amorphous silicon emitter layer having a doping type different from that of the silicon substrate; and an intrinsic amorphous silicon passivation layer formed between the crystalline silicon substrate and the amorphous silicon emitter layer, wherein the HIT solar cell further includes a transparent conductive oxide layer made of ZnO on an upper surface thereof, and the surface of the crystalline silicon substrate is not textured but only the surface of the transparent conductive oxide layer is textured, and thereby a very thin crystalline silicon substrate can be used, ultimately achieving an ultra-thin HIT solar cell having a very low total thickness while maintaining light trapping capacity.

Abstract: Disclosed is a method of manufacturing a CI(G)S-based thin film, in which a slurry prepared by mixing two or more kinds of binary nanoparticles containing CI(G)S-based elements, a solution precursor containing a CI(G)S-based element, an alcoholic solvent and a chelating agent is used to reduce the carbon layer formed between the CI(G)S-based thin film and molybdenum, and which includes (a) mixing two or more kinds of binary nanoparticles containing CI(G)S-based elements, a solution precursor containing a CI(G)S-based element, an alcoholic solvent and a chelating agent, thus preparing a slurry; (b) subjecting the slurry to non-vacuum coating, thus forming a CI(G)S-based thin film; and (c) subjecting the CI(G)S-based thin film to selenization heat treatment.

Abstract: A CIGS solar cell having a flexible substrate based on improved supply of Na. The CIGS solar cell includes a substrate formed of a flexible material, a rear electrode formed on the substrate, a CIGS light-absorption layer formed on the rear electrode, a buffer layer formed on the CIGS light-absorption layer, and a front electrode formed on the buffer layer, wherein the rear electrode comprise a single-layered Na-added metal electrode layer. A single-layered Na-added Mo electrode layer, specific resistance of which is about 1/10th the specific resistance under conditions of a process of forming a typical multilayer rear electrode, is applied to the rear electrode, thereby providing a CIGS solar cell having a flexible substrate and high conversion efficiency.

Abstract: According to an embodiment of the present invention, a gas-liquid circulating type gas hydrate reactor, includes: a reactor body configured to be supplied with gas and water to generate a gas hydrate; and a bubble generator configured to be disposed around a lower portion of the reactor body, wherein the gas supplied from the lower portion of the reactor body is jetted into the reactor body through the bubble generator. The gas-liquid circulating type gas hydrate reactor in accordance with the present invention makes it possible to jet gas at a high speed by using the bubble generator disposed at the low portion of the reactor body so as to promote the reaction of water and gas which are accommodated in the reactor body while forming a water stream at the lower portion of the reactor body that enables a smooth agitation of the water and the gas.

Abstract: An apparatus and method for measurement of radiation intensity for testing reliability of a solar cell, and a method for testing the reliability of the solar cell. The apparatus includes a first solar cell receiving a predetermined intensity of radiation or more to generate electricity, a second solar cell receiving a predetermined intensity of radiation or more to generate electricity; a temperature sensor sensing a temperature of the second solar cell; a cooler cooling the first solar cell; and a controller measuring the intensity of radiation applied to the first solar cell, and controlling the cooler to prevent the temperature of the first solar cell from increasing above a predetermined temperature depending on the temperature of the second solar cell sensed by the temperature sensor.

Abstract: A method for manufacturing a CZTS based thin film having a dual band gap slope, comprising the steps of: forming a Cu2ZnSnS4 thin film layer; forming a Cu2ZnSn(S,Se)4 thin film layer; and forming a Cu2ZnSnS4 thin film layer. A method for manufacturing a CZTS based solar cell having a dual band gap slope according to another aspect of the present invention comprises the steps of: forming a back contact; and forming a CZTS based thin film layer on the back contact by the method described above.

Abstract: A method of fabricating a CIGS thin film for solar cells using a simplified co-vacuum evaporation process and a CIGS thin film fabricated by the method are disclosed. The method includes: (a) depositing Cu, Ga and Se on a substrate having a substrate temperature ranging from 500° C. to 600° C. through co-vacuum evaporation, (b) depositing Cu, Ga, Se and In through co-vacuum evaporation while maintaining the same substrate temperature as in step (a), and (c) depositing Ga and Se through co-vacuum evaporation, followed by depositing Se alone through vacuum evaporation while lowering the temperature of the substrate. The method can realize crystal growth and band-gap grading by Ga composition distribution while simplifying process steps and significantly reducing a film-deposition time, as compared with a conventional co-vacuum evaporation process, thereby providing improvement in process efficiency.

Abstract: A method for manufacturing a CI(G)S-based thin film using a Cu—Se two-component nanoparticle flux, and a CI(G)S-based thin film manufactured by the method are provided. The method for manufacturing the CI(G)S-based thin film, according to the present invention, comprises the steps of: manufacturing Cu—Se two-component nanoparticles and In nanoparticles; manufacturing a slurry comprising the Cu—Se two-component nanoparticles by mixing the Cu—Se two-component nanoparticles, a solvent, and a binder, and manufacturing a slurry comprising the In nanoparticles by mixing the In nanoparticles, a solvent, and a binder; forming a thin film in which a plurality of layers are laminated by alternately coating the slurry comprising the Cu—Se two-component nanoparticles and the slurry comprising the In nanoparticles on a substrate, regardless of order; and heat-processing the thin film which is formed.

Abstract: A Cu—In—Zn—Sn—(Se,S)-based thin film for a solar cell and a preparation method thereof, and more particularly, to a Cu—In—Zn—Sn—(Se,S)-based thin film for a solar cell which can reduce an amount of In to be used and exhibit an excellent conversion efficiency and a preparation method thereof.

Abstract: A valve for preventing freeze-fracturing prevents accidental freeze-fracturing due to the freezing of water by draining water from a flow pipe before the danger of freezing occurs when the temperature of ambient air drops. The valve for preventing freeze-fracturing includes a housing coupled to a pipe port and a draining chamber provided in a portion of the housing that faces the pipe port. The draining chamber has therein a water inlet hole, which communicates with an inside of the flow pipe, and a water outlet hole, which communicates with an outside of the housing. A storage chamber is provided in a portion of the housing that is opposite the draining chamber, and contains therein a phase change material, which decreases in volume while changing in phase from liquid to solid. A plunger is movably disposed in the draining chamber to open and close the water inlet hole.

Abstract: Disclosed is a double-structure transparent conducting film having both excellent electrical characteristics and excellent light trapping performance, and a method of manufacturing the same. The double-structure transparent conducting film, which is used as a front antireflection film, a front electrode or a rear reflective film of a solar cell, includes: a light transmitting layer; and a light trapping layer whose one side is in contact with the light transmitting layer and whose other side is provided thereon with a surface textured structure; wherein the relationship of electrical conductivity A of the light transmitting layer and electrical conductivity a of the light trapping layer is A>a, and the relationship of etchability of the light transmitting layer and etchability of the light trapping layer is B<b.

Abstract: A method of forming a nanometer-scale prominence and depression structure on a zinc oxide thin film in a wet-etching method, and the method includes the steps of: preparing a substrate; forming a nano structure having a height and a width of a nanometer range; forming the zinc oxide thin film on the substrate on which the nano structure is formed; and wet-etching the zinc oxide thin film, in which in the wet-etching step, zinc oxide having relatively low physical compactness is preferentially etched since the zinc oxide is positioned on the nano structure, and thus the prominence and depression structure is formed around the nano structure by the etching. The method is effective in that a thin film can be uniformly formed on the prominence and depression structure, and an electrolyte or an organic material may uniformly penetrate between the prominence and depression structure.

Abstract: Disclosed are a high density CIS thin film and a method of manufacturing the same, which includes coating CIS nanopowders, CIGS nanopowders or CZTS nanopowders on a substrate by non-vacuum coating, followed by heat treatment with cavities between the nanopowders filled with filling elements such as copper, indium, gallium, zinc, tin, and the like. The high density CIS thin film is applied to a photo-absorption layer of a thin film solar cell, thereby providing a highly efficient thin film solar cell.

Abstract: An apparatus and method for measurement of radiation intensity for testing reliability of a solar cell, and a method for testing the reliability of the solar cell. The apparatus includes a first solar cell receiving a predetermined intensity of radiation or more to generate electricity, a second solar cell receiving a predetermined intensity of radiation or more to generate electricity; a temperature sensor sensing a temperature of the second solar cell; a cooler cooling the first solar cell; and a controller measuring the intensity of radiation applied to the first solar cell, and controlling the cooler to prevent the temperature of the first solar cell from increasing above a predetermined temperature depending on the temperature of the second solar cell sensed by the temperature sensor.

Abstract: Disclosed are a high density CIS thin film and a method of manufacturing the same, which includes coating CIS nanopowders, CIGS nanopowders or CZTS nanopowders on a substrate by non-vacuum coating, followed by heat treatment with cavities between the nanopowders filled with filling elements such as copper, indium, gallium, zinc, tin, and the like. The high density CIS thin film is applied to a photo-absorption layer of a thin film solar cell, thereby providing a highly efficient thin film solar cell.

Abstract: A valve for preventing freeze-fracturing prevents accidental freeze-fracturing due to the freezing of water by draining water from a flow pipe before the danger of freezing occurs when the temperature of ambient air drops. The valve for preventing freeze-fracturing includes a housing coupled to a pipe port and a draining chamber provided in a portion of the housing that faces the pipe port. The draining chamber has therein a water inlet hole, which communicates with an inside of the flow pipe, and a water outlet hole, which communicates with an outside of the housing. A storage chamber is provided in a portion of the housing that is opposite the draining chamber, and contains therein a phase change material, which decreases in volume while changing in phase from liquid to solid. A plunger is movably disposed in the draining chamber to open and close the water inlet hole.

Abstract: A Cu-In-Zn-Sn-(Se,S)-based thin film for a solar cell and a preparation method thereof, and more particularly, to a Cu-In-Zn-Sn-(Se,S)-based thin film for a solar cell which can reduce an amount of In to be used and exhibit an excellent conversion efficiency and a preparation method thereof.