Abstract: A solar cell includes a photoelectric conversion layer, a first electrode on one surface of the photoelectric conversion layer, a second electrode on other surface of the photoelectric conversion layer, and a third electrode on the other surface of the photoelectric conversion layer. The third electrode is substantially rectangular with its corners rounded off in the in-plane direction of the photoelectric conversion layer, and overlaps the second electrode at the periphery thereof.

Abstract: A solar cell includes a photoelectric conversion substrate, a first electrode on one surface of the substrate, a second electrode on the other surface of the substrate, and a third electrode on the other surface of the substrate. The third electrode extracts electric power from the second electrode, and overlaps the second electrode at the periphery in the in-plane direction of the photoelectric conversion substrate. The thickness of the second electrode is larger than that of the third electrode, and the difference between the thickness of the second electrode and that of the third electrode is not less than 10 micrometers and not more than 30 micrometers.

Abstract: When forming an electrode by printing several times, the cross section area of the electrode is increased and the resistance is reduced while more electrode material is required, which leads to a cost up and waste of resources. There is provided a solar cell manufacturing method for forming an electrode of a predetermined pattern by repeating printing on a substrate surface by a predetermined number of times. A mask pattern for printing the entire predetermined pattern is used at least once among the predetermined number of printings while mask patterns, each for printing a part of the predetermined pattern, are used in the other printings, thereby forming the electrode of the predetermined pattern.

Abstract: A semiconductor laser includes a first conductivity type GaAs substrate; a AlGaAs double heterojunction structure disposed on the GaAs substrate and including an upper cladding layer having a mesa ridge stripe with a side surface that makes an angle larger than 90.degree. with a front surface of the upper cladding layer; a first current blocking layer of first conductivity type AlGaAs; and a second current blocking layer of first conductivity type AlGaAs, the first and second current blocking layers covering the mesa ridge stripe. The Al compositions of the first and second current blocking layers are larger than that of the upper cladding layer, maintaining an equivalent refractive index of an active region higher than that of other portions of the semiconductor laser. As a result, the differences between the lattice constant of the second current blocking layer and the GaAs substrate or the AlGaAs upper cladding layer are smaller than in prior art semiconductor lasers.

Abstract: A pulsation laser includes an n-type AlGaAs cladding layer on an n-type GaAs substrate, three quantum well active layers having central increased thickness regions and disposed on the cladding layer, and a p-type AlGaAs cladding layer disposed on the quantum well active layer. The increased thickness region of the active layer is not more than one-quarter of the length of the resonator of the laser.

Abstract: A method of fabricating a semiconductor laser device includes successively forming an active layer and upper cladding layers on a lower cladding layer, etching and removing portions except regions of the upper cladding layers where a current is to flow to form a stripe-shaped ridge structure, and forming a buffer layer comprising Al.sub.x Ga.sub.1-x As having an Al composition ratio x of 0 to 0.3 on a surface of the upper cladding layers exposed by the etching and forming a current blocking layer of first conductivity type Al.sub.y Ga.sub.1-y As having an Al composition ratio y of at least 0.5 on the buffer layer to bury portions of the upper cladding layers which are not removed by the etching process. Therefore, since the layer grown on the upper cladding layer exposed by etching of AlGaAs or GaAs having a low Al composition ratio (0-0.3), three-dimensional growth of and crystalline defects in the buffer layer are suppressed.

Abstract: A semiconductor laser includes a ridge structure includes a cladding layer having a thermal expansion coefficient. Current blocking structures are disposed at both sides of the ridge structure and include Al.sub.x Ga.sub.1-x As first current blocking layers having an Al composition x larger than 0.7 and contacting the ridge structure. In this structure, even when the Al composition of the first current blocking layers is reduced at both sides of the ridge structure, the wavelength of light absorbed by the first current blocking layers does not exceed the wavelength of laser light produced in the active layer. Therefore, unwanted absorption of the laser light at both sides of the ridge structure is avoided, resulting in a semiconductor laser with improved laser characteristics.

Abstract: A semiconductor laser device includes a semiconductor substrate of a first conductivity type; opposed light emitting facets; a double heterojunction structure disposed on the semiconductor substrate and including an optical waveguide that extends between the facets and comprises a light emitting region and a lens region, the lens region being between the light emitting region and one of the facets, the double heterojunction structure including a plurality of AlGaAs series compound semiconductor layers which are thicker in the light emitting region than in the lens region; and a current blocking structure disposed on both sides of the double heterojunction structure and including a lower AlGaAs series compound semiconductor layer of the first conductivity type, an intermediate AlGaAs series compound semiconductor layer of a second conductivity type, opposite the first conductivity type, and an upper AlGaAs series compound semiconductor layer of the first conductivity type.

Abstract: A semiconductor laser device includes, on a first conductivity type GaAs substrate, successively, a first conductivity type GaAs buffer layer, a first conductivity type Al.sub.s Ga.sub.1-s As (0<s<1) cladding layer, a quantum well active layer having a structure that can produce an oscillation wavelength of 0.9.about.1.2 .mu.m and including a well layer comprising In.sub.x Ga.sub.1-x As (0<x<1) and a barrier layer comprising Al.sub.y Ga.sub.1-y As (0<y<s), a second conductivity type Al.sub.t Ga.sub.1-t As (1<t<y) upper cladding layer, a second conductivity type GaAs contact layer, and a multiple reflection film layer alternatingly laminating first and second semiconductor materials which have the same conductivity type as the adjacent semiconductor materials and have the different refractive indices in number of layers, first and second electrodes, and a pair of laser resonator facets perpendicular to the active layer and the multiple reflection film layer.

Abstract: A semiconductor device includes a semiconductor substrate, a strained multi-quantum well with alternatingly laminated first barrier layers and well layers with second barrier layers as outermost layers of the strained MQW structure. The strained MQW structure has a safety factor K.sub.safe =3.9; and ##EQU1## Therefore, it is possible to make the strained MQW structure have a sufficient margin with respect to critical conditions concerning the generation of dislocations, and deterioration of operational characteristics in continuous operation of the semiconductor device can be suppressed so that the reliability of the semiconductor device is enhanced.

Abstract: A metal organic compound container apparatus for containing a liquid metal organic compound, receiving a carrier gas, and producing a carrier gas stream saturated with vapor of the metal organic compound including a container for containing a liquid metal organic compound; an inlet pipe for introducing a carrier gas into the container, the inlet pipe having an end for immersion in the metal organic compound; a carrier gas flow rate controller for controlling carrier gas flow into the inlet pipe; a first exhaust pipe for exhausting carrier gas from the container at a first flow rate, the first exhaust pipe having an end not contacting the metal organic compound; a first gas flow rate controller for controlling one of pressure and the first flow rate of the carrier gas through the first exhaust pipe; a second exhaust pipe for exhausting carrier gas from the container at a second flow rate, the second exhaust pipe having an end not contacting the metal organic compound; and a second gas flow rate controller for

Abstract: A semiconductor laser including a semiconductor substrate of a first conductivity type; a semiconductor multilayer structure disposed on the substrate and including a first cladding layer of the first conductivity type, an active layer, a second cladding layer of a second conductivity type, opposite the first conductivity type, and a current blocking layer of the first conductivity type; a laser light emitting facet; a stripe-shaped V groove extending in a resonator length direction transverse to the laser light emitting facet and penetrating in a depth direction into a part of the semiconductor multilayer structure, including into the second cladding layer, the stripe-shaped V groove having a width transverse to the resonator length direction and the depth direction wherein at least one of the depth and width of the stripe-shaped V groove has a first dimension adjacent the laser light emitting facet and a second dimension, different from the first dimension, within the semiconductor laser spaced from the las

Abstract: An apparatus for producing a compound semiconductor layer includes a first flow rate controller for adjusting flow rates of respective material source gases, a gas mixing pipe for mixing the respective material source gases, gas distributing pipes for distributing gases and connected to the gas mixing pipe, a second flow rate controller for adjusting flow rates of the material source gases flowing through the gas distributing pipes and for supplying the material source gases to a reaction tube, a pressure detector for detecting pressure in the gas mixing pipe, and a third controller responsive to the pressure detector for controlling the second flow rate controller to maintain a constant pressure in the gas mixing pipe. Retardation of the gases between the first and second flow rate controllers is avoided, improving thickness uniformity in grown layers.