Abstract: The property of CIS based thin-film solar cell modules that the modules recover their conversion efficiency, etc. upon irradiation with a weak light is correctly evaluated. A CIS based thin-film solar cell module is subjected to a conventional damp heat test with a constant-light solar simulator (solar simulator) 1D in such a manner that the power of the light source 1E is regulated so that the solar simulator 1D emits a weak light corresponding to the amount of solar radiation in cloudy weather, i.e., resulting in an irradiance of 100-300 W/m2, and the module is continuously irradiated with the weak light throughout the test period under the same temperature, humidity, and storage period conditions as those in the conventional conditions for the test (1,000-hour storage in the dark at a temperature of 85° C. and a relative humidity of 85%).

Abstract: In order to manufacture a CIS-based thin film solar cell that can achieve high photoelectric conversion efficiency by adding an alkali element to a light absorbing layer easily and with good controllability, a backside electrode layer (2) is formed on a substrate (1). Then, a p-type CIS-based light absorbing layer (3) is formed on backside electrode layer (2), and then an n-type transparent and electroconductive film (5) is formed on this p-type CIS-based light absorbing layer (3). At this time, the backside electrode layer (2) is constituted by forming a first electrode layer (21) using a backside electrode material in which an alkali metal is mixed and, then forming a second electrode layer (22) using the backside electrode material that does not substantially contain the alkali metal.

Abstract: A method of manufacturing a CIS-based thin film solar cell that achieves high photoelectric conversion efficiency comprises: forming a backside electrode layer on a substrate; forming a p-type CIS-based light absorbing layer thereon; and further forming an n-type transparent and electrically conductive film. The above-mentioned forming a p-type CIS-based light absorbing layer comprises: forming a metal precursor film (30a) at least comprising a first metal layer (31, 32) containing a I group element and a second metal layer (33) containing a III group element; and selenizing and/or sulfurizing the metal precursor film, and the above-mentioned forming the metal precursor film includes forming either one of the first metal layer (31, 32) or the second metal layer (33) of at least two layers including a layer (31) that contains an alkali metal and a layer (32) that substantially does not contain the alkali metal.

Abstract: In order to manufacture a CIS-based thin film solar cell that can achieve high photoelectric conversion efficiency by adding an alkali element to a light absorbing layer easily and with good controllability, a backside electrode layer (2) is formed on a substrate (1). Then, a p-type CIS-based light absorbing layer (3) is formed on backside electrode layer (2), and then an n-type transparent and electroconductive film (5) is formed on this p-type CIS-based light absorbing layer (3). At this time, the backside electrode layer (2) is constituted by forming a first electrode layer (21) using a backside electrode material in which an alkali metal is mixed and, then forming a second electrode layer (22) using the backside electrode material that does not substantially contain the alkali metal.

Abstract: The property of CIS based thin-film solar cell modules that the modules recover their conversion efficiency, etc. upon irradiation with a weak light is correctly evaluated. A CIS based thin-film solar cell module is subjected to a conventional damp heat test with a constant-light solar simulator (solar simulator) 1D in such a manner that the power of the light source 1E is regulated so that the solar simulator 1D emits a weak light corresponding to the amount of solar radiation in cloudy weather, i.e., resulting in an irradiance of 100-300 W/m2, and the module is continuously irradiated with the weak light throughout the test period under the same temperature, humidity, and storage period conditions as those in the conventional conditions for the test (1,000-hour storage in the dark at a temperature of 85° C. and a relative humidity of 85%).

Abstract: A simple device is used to make the temperature in an apparatus even and improve the state of being in contact with reactant gases, selenium, and sulfur. A fan 3 as a device for atmosphere homogenization is disposed in an apparatus, and the work is disposed in the manner which enables a reactant gas to circulate smoothly. Namely, flat platy works 2 are disposed apart from each other at a certain distance parallel to the direction of the major axis of the apparatus while keeping the plates vertical so that the apparatus has passages within the group of works and has gas passages over and under the works and on both sides thereof. Thus, each work is apt to come into contact with the reactant gases in the apparatus and the temperature in the apparatus is even. The state of being in contact with the reactant gases, selenium, and sulfur is improved.

Abstract: The triethylaluminum contained as an impurity in low-purity raw-material diethylzinc, which is inexpensive, is utilized as an additive to reduce the cost of film formation. Diethylzinc having a low purity (99.99-98% or 99.99-90%) is used as a raw material to produce a ZnO transparent conductive film by the MOCVD (metal-organic chemical vapor deposition) method. Water vapor (H2O) is used as an oxidizing agent and the triethylaluminum contained as an impurity in the raw material is utilized as an additive (diborane is further added as an additive) to cause the diethylzinc, the water vapor (H2O), and the triethylaluminum (and the diborane) to undergo a vapor-phase reaction to produce a ZnO transparent conductive film.

Abstract: Film formation is conducted at a low temperature to improve conversion efficiency and productivity and to enable a wider choice of substrate materials to be used. The invention relates to the light absorption layer of a CIS compound semiconductor thin-film solar cell and to a method of forming the layer. The light absorption layer comprises a compound represented by Cux(In1-yGay)(Se1-zSz)2 and having a chalcopyrite type structure, the proportions of the components satisfying 0.86?x?0.98, 0.05?y?0.25, 0?z?0.3, x=?T+?, ?=0.015y?0.00025, and ?=?7.9y+1.105, provided that T (° C.) is anneal temperature and the allowable range for x is ±0.02. The layer is formed by the selenization method at a low temperature (about 500?T?550). As the substrate is used a soda-lime glass having a low melting point.

Abstract: A precursor film having a required gallium component proportion is formed easily at low cost. A precursor film for use in forming the light absorption layer of a CIS type thin-film solar cell, etc., or a method for forming the film are provided. A Cu—Ga layer having a high gallium component proportion (Ga/(Ga+Cu)) of X % by weight Ga is formed as a first layer by sputtering using a precursor film comprising a Cu—Ga alloy layer having the gallium component proportion of X % by weight Ga as a target (deposition step A). Thereafter, a copper layer is formed as a second layer on the first layer by sputtering using a copper layer as a target (deposition step B) to thereby form a precursor film having the required gallium component proportion of Y % (X>Y) by weight Ga as the sum of the first layer and second layer. A method of film formation by simultaneous vapor deposition is also possible.