Abstract: A solar cell which comprises a back metal electrode and a light-absorbing layer comprising a p-type CIGS semiconductor on a substrate in this order, wherein the solar cell further comprises a p-type or low carrier concentration n-type semiconductor layer comprising ZnO between the light-absorbing layer and the back metal electrode, and a process for producing the solar cell.

Abstract: A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.

Abstract: A light-emitting device includes a silicon substrate, a ZnOSSe layer provided on the silicon substrate that is lattice-matched to the silicon substrate, and a separate confinement heterostructure light-emitting layer that is provided on the ZnOSSe layer and includes an active layer and upper and lower clad layers.

Abstract: A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.

Abstract: A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.

Abstract: In the case in which a ZnO based oxide semiconductor layer is to be hetero-epitaxially grown on a substrate formed of a material which is different from that of a ZnO based oxide semiconductor, the ZnO based oxide semiconductor layer is grown at a high temperature of 500° C. or more, and supply of oxygen is stopped and gradual cooling is carried out until a substrate temperature is lowered to 350° C. or less after the growth of the ZnO based oxide semiconductor layer is completed. As a result, it is possible to suppress the generation of dislocations or crystal defects over an epitaxial grown layer based on the atmosphere while the substrate temperature is lowered after the growth of the semiconductor layer and a difference in a coefficient of thermal expansion, thereby obtaining a semiconductor device having a high quality ZnO based oxide semiconductor layer which has an excellent crystalline property and a semiconductor light emitting device having the high characteristics.

Abstract: A ZnO based oxide semiconductor layer is grown on a sapphire substrate 1 by supplying, for example, raw materials made of Zn and O constituting ZnO and a p-type dopant material made of N without supplying an n-type dopant material (a-step). By stopping the supply of the material of O and further supplying an n-type dopant material made of Ga, the semiconductor layer is doped with the p-type dopant and the n-type dopant, thereby forming a p-type ZnO layer (2a) (b-step). By repeating the steps (a) and (b) plural times, a p-type ZnO based oxide semiconductor layer is grown. As a result, N to be the p-type dopant can be doped in a stable carrier concentration also during high temperature growth in which a residual carrier concentration can be reduced, and the carrier concentration of the p-type layer made of the ZnO based oxide semiconductor can be increased sufficiently.

Abstract: A method of producing a semiconductor film of Cu(MIII)(MVI)2 wherein MIII represents In1-xGax where x is between 0 and 1 and MVI represents SeyS1-y where y is between 0.5 and 1, including the steps of: (a) depositing on a substrate a precursor Cu(MIII)(MVI)2 film having a molar ratio of Cu:MIII of less than 1.0:1.0 but not less than 1.0:1.4 and (b) annealing the precursor film at a temperature of 400-500° C. in an oxygen-containing atmosphere to form a buffer layer of indium oxide and/or gallium oxide and a Cu(In1-xGax)(SeyS1-y)2 film interposed between the substrate and the buffer layer. The buffer layer may be removed by etching with an acid.

Abstract: A substrate such as a sapphire substrate or the like is set to a molecular beam epitaxy (MBE) apparatus. Next, the temperature of the substrate is elevated to the temperature which is lower than the temperature at which a predetermined ZnO based oxide semiconductor layer (i.e. function layer) is grown (S1). Then, raw materials containing oxygen radical is irradiated to the substrate to grow a buffer layer made of ZnO based oxide semiconductor (S2). Subsequently, the irradiation of oxygen radical is stopped so as to eliminate the influence of oxygen onto the buffer layer (S3). Then, the temperature of the substrate is elevated to the temperature at which the predetermined ZnO based oxide semiconductor layer is grown (S4). After that, raw materials containing oxygen radical is irradiated so as to sequentially grow a ZnO based oxide semiconductor layer as a function layer (S5).

Abstract: A light-emitting device includes a silicon substrate, a ZnOSSe layer provided on the silicon substrate that is lattice-matched to the silicon substrate, and a separate confinement heterostructure light-emitting layer that is provided on the ZnOSSe layer and includes an active layer and upper and lower clad layers.

Abstract: A method of producing a semiconductor film of Cu(MIII) (MVI)2 wherein MIII represents In1−xGax where x is between 0 and 1 and MVI represents SeyS1−y where y is between 0.

Abstract: The closing plates (61b), (61c) are provided on the both end portions of the cylindrical insulator body (61a), the gas introduction tube for introducing a gaseous substance is inserted into one plate (61b) of the closing plates of the plasma chamber (61) for making the gaseous substance plasmatic within it, and on the other plate (61c), the plasma radiation outlet (61d) is provided. Then, nearby the plasma jet (63) outgoing from the radiation outlet, the electrode (64) for applying a high electric field of an ion trapper is provided so as to be opposed to the grounded electrode (65) interposed the plasma jet between them. This electrode for applying a high electric field is fixed on the grounded metal plate (61e) provided on the other plate (61c) via the insulation porcelain (66) made of MgO or quartz.

Abstract: In the case in which a ZnO based oxide semiconductor layer is to be hetero-epitaxially grown on a substrate formed of a material which is different from that of a ZnO based oxide semiconductor, the ZnO based oxide semiconductor layer is grown at a high temperature of 500° C. or more, and supply of oxygen is stopped and gradual cooling is carried out until a substrate temperature is lowered to 350° C. or less after the growth of the ZnO based oxide semiconductor layer is completed. As a result, it is possible to suppress the generation of dislocations or crystal defects over an epitaxial grown layer based on the atmosphere while the substrate temperature is lowered after the growth of the semiconductor layer and a difference in a coefficient of thermal expansion, thereby obtaining a semiconductor device having a high quality ZnO based oxide semiconductor layer which has an excellent crystalline property and a semiconductor light emitting device having the high characteristics.

Abstract: A ZnO based oxide semiconductor layer is grown on a sapphire substrate 1 by supplying, for example, raw materials made of Zn and O constituting ZnO and a p-type dopant material made of N without supplying an n-type dopant material (a-step). By stopping the supply of the material of O and further supplying an n-type dopant material made of Ga, the semiconductor layer is doped with the p-type dopant and the n-type dopant, thereby forming a p-type ZnO layer (2a) (b-step). By repeating the steps (a) and (b) plural times, a p-type ZnO based oxide semiconductor layer is grown. As a result, N to be the p-type dopant can be doped in a stable carrier concentration also during high temperature growth in which a residual carrier concentration can be reduced, and the carrier concentration of the p-type layer made of the ZnO based oxide semiconductor can be increased sufficiently.

Abstract: In an LED, for example, a light emitting layer forming portion (10) composed of a ZnO based oxide semiconductor is provided on a substrate (11), which includes at least an n-type layer (14) and a p-type layer (16) to form a light emitting layer. The p-type layer (16) contains phosphorus as a dopant. In order to dope such phosphorus, for example, a material having a bond of Zn and P such as Zn3P2 is used when growing a ZnO based oxide semiconductor. As a result, it is possible to obtain a semiconductor device including a p-type ZnO based oxide semiconductor layer having a stable and high carrier concentration and a method of manufacturing the semiconductor device.

Abstract: The closing plates (61b), (61c) are provided on the both end portions of the cylindrical insulator body (61a), the gas introduction tube for introducing a gaseous substance is inserted into one plate (61b) of the closing plates of the plasma chamber (61) for making the gaseous substance plasmatic within it, and on the other plate (61c), the plasma radiation outlet (61d) is provided. Then, nearby the plasma jet (63) outgoing from the radiation outlet, the electrode (64) for applying a high electric field of an ion trapper is provided so as to be opposed to the grounded electrode (65) interposed the plasma jet between them. This electrode for applying a high electric field is fixed on the grounded metal plate (61e) provided on the other plate (61c) via the insulation porcelain (66) made of MgO or quartz.

Abstract: A substrate such as a sapphire substrate or the like is set to a molecular beam epitaxy (MBE) apparatus. Next, the temperature of the substrate is elevated to the temperature which is lower than the temperature at which a predetermined ZnO based oxide semiconductor layer (i.e. function layer) is grown (S1). Then, raw materials containing oxygen radical is irradiated to the substrate to grow a buffer layer made of ZnO based oxide semiconductor (S2). Subsequently, the irradiation of oxygen radical is stopped so as to eliminate the influence of oxygen onto the buffer layer (S3). Then, the temperature of the substrate is elevated to the temperature at which the predetermined ZnO based oxide semiconductor layer is grown (S4). After that, raw materials containing oxygen radical is irradiated so as to sequentially grow a ZnO based oxide semiconductor layer as a function layer (S5).

Abstract: In such a construction that an active layer (5) for emitting light when a current is injected thereto is sandwiched between an n-type clad layer (4) and a p-type clad layer (6) which are made of a material having a larger band gap than that of the active layer, the above-mentioned active layer (5) is made of a compound semiconductor containing Zn, o, and a group VI type element other than O. As a result, it is possible to obtain such a semiconductor light emitting device as a blue type LED or LD, which is made of the harmless material and does not include Cd specifically, while using a ZnO-based compound semiconductor of narrow band gap with fewer crystal defects and excellent in crystallinity as a material of its active layer sandwiched between clad layers, and also improving its light emitting properties.

Abstract: A method of fabricating Cu&agr;(InxGa1−x)&bgr;(SeyS1−y)&ggr; films for solar cells includes forming an electrode on a substrate and supplying the substrate and electrode with Cu, In, Ga, Se, and S to form a Cu&agr;(InxGa1−x)&bgr;(SeyS1−y)&ggr; film. Simultaneously with the supplying of Cu, In, Ga, Se and S, the substrate is supplied with water vapor or a gas that contains a hydroxyl group.

Abstract: A refrigerator-freezer includes a first evaporator cooling an atmosphere in a refrigerating compartment, a second evaporator cooling an atmosphere in a freezing compartment and a controller controlling a switching valve in a refrigerating cycle so that a cooling operation is switched between a first operation mode in which refrigerant compressed by a compressor is supplied at least to the first evaporator and a second operation mode in which the refrigerant compressed by the compressor is supplied at least to the second evaporator. The controller stops the compressor when a temperature in either one of the refrigerating and freezing compartments for which the cooling operation is unexecuted is below a predetermined upper limit temperature in a case where a temperature in the other compartment for which the cooling operation is in progress drops to a predetermined lower limit temperature.