Abstract: A surface-normal optoelectronic device is provided which includes a first semiconductor layer of a first electroconductive type, a second semiconductor layer of a second electroconductive type having a polarity inverse to that of the first electroconductive type, a semiconductor active layer, a third semiconductor layer of the first electroconductive type, and a fourth semiconductor layer of the second electroconductive type, formed on a semiconductor substrate. The second and third layers are larger in forbidden band width than the active layer, said second layer is smaller in forbidden band width than a part of the first layer contacting the second layer, and the third layer is smaller in forbidden band width than a part of the fourth layer contacting the third layer. High resistance regions are formed vertically passing through the active layer, to surround its light-emitting region and to have a resistance higher than that of that region.

Abstract: Disclosed is a photo semiconductor material characterized in the blue to ultraviolet wavelength region. The semiconductor is firmed by lattice matching a sulfide-selenide manganese-zinc epitaxial mixed crystal film to the substrate. A blue laser diode is fabricated by forming a double hereto quantum well structure on a substrate by using sulfide-selenide manganese-zinc mixed crystal films as clad layers. A zinc molecular beam, a manganese molecular beam, a sulfur molecular beam, and a selenium molecular beam are simultaneously emitted onto a GaAs substrate in an ultrahigh vacuum, and a mixed crystal of Zn.sub.1-x Mn.sub.x S.sub.y Se.sub.1-y (0<x<1, 0<y<1) is obtained. In particular, the molecular beam pressure is adjusted so as to lattice matched to the substrate. As the material for the substrate, for example, GaAs and ZnSe may be used. Moreover, on an n-type GaAs single crystal substrate, a 2 .mu.m thick chlorine doped n-type Zn.sub.0.8 Mn.sub.0.2 S.sub.0.2 Se.sub.0.

Abstract: An optical semiconductor device with wavelength selectivity comprises a substrate, a collector layer provided on said substrate and composed of a semiconductor having a first conductive type, a multiple quantum well layer provided on said collector layer, a base layer provided on said multiple quantum well layer and composed of a semiconductor having a second conductive type, said base layer consisting of an active layer, and first and second semiconductor layers with said active layer sandwiched therebetween and having a wider band gap than said active layer, said base layer and said multiple quantum well layer propagating light, an emitter layer provided on said base layer and composed of a semiconductor having the first conductive type, and a collector electrode, a base electrode and an emitter electrode electrically connected to said collector layer, base layer and emitter layer, respectively.

Abstract: In a light emitting device comprising a first clad layer composed of a mixed crystal compound semiconductor of first type conductivity, an active layer composed of a mixed crystal compound semiconductor of first type conductivity which has the mixed crystal ratio required to emit the prescribed wavelength, and a second clad layer composed of a mixed crystal compound semiconductor of second type conductivity which has a mixed crystal ratio equivalent to that of the first clad layer, the active layer is sandwiched by the first and second clad layers and forms the double hetero structure with the first and second clad layers, and the carrier concentration in the first clad layer near the junction with the active layer was made to be 5.times.10.sup.16 cm.sup.-3 or less. The carrier concentration in the active layer is preferably 1.times.10.sup.17 cm.sup.-3 or less, and the carrier concentration in the second clad layer is preferably 5.times.10.sup.16 cm.sup.-3 or more.

Abstract: A shift register according to the present invention includes: a plurality of first electrodes; at least one second electrode; a voltage application unit for applying a voltage to each of the plurality of first electrodes; a plurality of optically bistable elements connected to each of the plurality of first electrodes and at least one second electrode; and an optical waveguide layer for optically coupling the plurality of optically bistable elements to each other.

Abstract: A semiconductor light-emitting device comprises a light-emitting layer including a pn junction formed by a plurality of In.sub.x Ga.sub.y Al.sub.1-x-y P (0.ltoreq.x, y.ltoreq.1) layers, and a light-emitting-layer holding layer consisting of an indirect transition type Ga.sub.1-w Al.sub.w As (0.ltoreq.w.ltoreq.1) provided on an opposite side to a light-outputting side. The holding layer has a sufficiently small light absorption coefficient for the light from the light-emitting layer although its band gap is small and improves the light emission efficiency of the semiconductor light-emitting device.

Abstract: A semiconductor-insulator-semiconductor (SIS) structure diode device for providing fast optoelectronic switching with stimulated emission. The device includes a substrate which has a buffer layer disposed on top thereof. An n-type cladding layer is disposed on top of the buffer layer. An undoped i-region is disposed on top of the buffer layer. The i-region includes at least one quantum well disposed between two waveguide layers. A lightly doped p-type cladding layer is disposed on top of the i-region. A contact layer is further disposed on top of the p-type cladding layer. First and second contact terminals are included for providing a two-terminal device. The diode advantageously provides good lasing performance, significant negative differential resistance and strong light sensitivity. In an alternate embodiment, a third terminal is connected to the undoped i-region to thereby form a three terminal device.

Abstract: In an organic electroluminescent device including first and second electrodes opposite to each other and a multi-layered body which is sandwiched between these electrodes and consists of a plurality of organic films including a light-emitting layer, a material for each organic film and electrode is selected so that electrons and holes are simultaneously and respectively injected from the first and second electrodes in the multi-layered body when a forward biasing voltage is applied, a large amount of injected electrons and holes are accumulated at the multi-layered body, and these electrons and holes are subjected to radiative recombination at a predetermined threshold voltage.

Abstract: A compound semiconductor device and a process for manufacturing it is disclosed. The process comprises the steps of forming a first conduction type first clad layer, a first conduction type or second conduction type activated layer, a second conduction type second clad layer, and a second conduction type cap layer upon a first conduction type semiconductor substrate, forming a first conduction type electrode and a second conduction type electrode, and forming a rectangular pole shaped laser diode, a triangular pole shaped detecting photo-diode, and a triangular pole shaped receiving photo-diode by carrying out a single round of anisotropic etching. According to the present invention, the high density can be easily realized, so that the power consumption and the manufacturing cost can be saved.

Abstract: Optoelectronic integrated circuits are disclosed comprising a vertical-cavity surface emitting laser (VCSEL) and a transistor. The VCSEL comprises a laser cavity sandwiched between two distributed Bragg reflectors. The laser cavity comprises a pair of spacer layers surrounding one or more active, optically emitting quantum-well layers having a bandgap in the visible range which serve as the active optically emitting material of the device. The thickness of the laser cavity is m .lambda./2n.sub.eff where m is an integer, .lambda. is the free-space wavelength of the laser radiation and n.sub.eff is the effective index of refraction of the cavity. Electrical pumping of the laser is achieved by heavily doping the bottom mirror and substrate to one conductivity-type and heavily doping the regions of the upper mirror with the opposite conductivity type to form a diode structure and applying a suitable voltage to the diode structure.

Abstract: In a semiconductor light-emitting element having a double hetero junction structure of an InGaAP system an n-type dopant, which does not change a crystal structure, is doped in an In.sub.1-y (Ga.sub.1-x Al.sub.x).sub.y P(0.ltoreq.x<1, y.perspectiveto.0.5) active layer, so that an n-type active layer (4), is formed between a p-type InGaAlP cladding layer (5), which has band-gap energy that is larger than that of the active layer (4), and an n-type InGaAlP cladding layer (3), thereby preventing the dopant of the P-type InGaAlP cladding layer (3) from being dispersed into the active layer (4). Thus, the oscillation wavelength of the light-emitting element is not shifted to a short wavelength, and the threshold current of the oscillation is not increased thereby providing an element which can improve yield and reliance.

Abstract: The present invention provides a p-n junction type blue luminescence device forming a p-type hole injection layer and having high light-emission efficiency. On an n-conduction type ZnS substrate 111, there is formed a multiquantum well structure 112 alternately laminating a p-type ZnTe layer 112a and a non-doped ZnS layer 112b. And, a positive electrode 113 and a negative electrode 114 are provided on the multiquantum well structure 112 and the ZnS crystal, respectively. By applying forward bias voltage on this light-emitting device, electrons are injected from the n-type ZnS substrate to the multiquantum well structure 112. Then, these electrons are recombined with holes in the multiquantum well structure 112, so as to emit blue luminescence light. Thus, it becomes possible to easily and reproducibly obtain a p-conduction type hole injection layer so as to realize highly concentrated carrier injection and obtain high efficiency in emitting blue luminescence light.

Abstract: An optical EXCLUSIVE-OR element in which the number of basic elements is reduced which results in increased integration of the element. The optical EXCLUSIVE-OR element comprises a substrate, a first optical functional element and a second optical functional element having the same structure as that of the first optical functional element. Each of the first and second optical functional elements has a light receiving portion and a light emitting portion. The light emitting portion is formed on the light receiving portion. The light emitting portion comprises semiconductor materials having an energy gap wider than the dominant peak energy of the input light, and the light receiving portion comprises semiconductor materials having an energy gap equal to or narrower than the dominant peak energy of the input light. A first electrode is formed over the first and second optical functional elements, and has windows which allow the input light and output light to pass through.

Abstract: A non-lasing edge-emitting LED (30) suitable for precision reflectometry has an absorber region (52) which is reverse-biased via a contact (58) to absorb light by Stark absorption or Franz-Keldysch effect. During operation, the gain region (50) is forward biased via contact (56) to produce light emission including stimulated emission from an edge of the device, The absorber region is sized to a length L.sub..alpha. >(gL.sub.g -1/21n(1/R.sub.1 R.sub.2))/.alpha. where g and .alpha. are coefficients of gain and absorption and R.sub.1 and R.sub.2 are the front and back facet (60, 64) reflectivities, such that round-trip power loss through the cavity is at least 60 dB. The length L.sub..alpha. is sufficient to preclude regenerative oscillation of light in the cavity during light emission including stimulated emission. Antireflection measures further reduce end facet reflectivity, limiting signal contributions due to internal reflections to less that -85 dB below the primary output signal.

Abstract: A semiconductor light-emitting device, such as LEDs AND laser diodes having emission wavelengths in a range which includes the blue to ultra-violet region of the spectrum are disclosed. The LED comprises a substrate and an p-n junction structure formed on the substrate, the p-n junction structure having first and second semiconductor layers, each consisting essentially of (Cu.sub.a Ag.sub.1-a)(Al.sub.b Ga.sub.1-b)(Se.sub.o S.sub.1-o).sub.2, wherein 0.ltoreq.a.ltoreq.1, 0.ltoreq.b.ltoreq.1, and 0.ltoreq.c.ltoreq.1, the first semiconductor layer being doped with N, P, or As, the second semiconductor layer being doped with Zn, Cd, Cl, Br, or I.

Abstract: A semiconductor light-emitting device comprises a light-emitting layer including a pn junction formed by a plurality of In.sub.x Ga.sub.y Al.sub.1-x-y P (0.ltoreq.x, y.ltoreq.1) layers, and a light-emitting-layer holding layer consisting of an indirect transition type Ga.sub.l-w Al.sub.w As (0.ltoreq.w.ltoreq.1) provided on an opposite side to a light-outputting side. The holding layer has a sufficiently small light absorption coefficient for the light from the light-emitting layer although its band gap is small and improves the light emission efficiency of the semiconductor light-emitting device.

Abstract: A light emitting diode (LED) including a light generation region situated on a light-absorbing substrate also includes a thick transparent layer which ensures that an increased amount of light is emitted from the sides of the LED and only a minimum amount of light is absorbed by the substrate. The thickness of the transparent layer is determined as a function of its width and the critical angle at which light is internally reflected within the transparent layer. The thick transparent layer is located either above, below or both above and below the light generation region. The thick transparent layer may be made of materials and with fabrication processes different from the light generation region.

Abstract: A high efficiency, high density light-emitting diode array which provides improved light output efficiency and suppression of crosstalk between adjacent light-emitting elements without loss of reliability or reproducibility is disclosed. The array includes isolated light-emitting elements on a substrate. Each light-emitting element has a light-emitting layer between a pair of cladding layers with heterojunctions being formed between the light-emitting layer and the cladding layers. Each light-emitting element has a light-emitting surface and the light-emitting layer of each light-emitting element is of an area no greater than the area of the light-emitting surface.

Abstract: A semiconductor device, in which the topography becomes flat and an LD is rapidly driven by an HBT since the HBT is formed in the vertical structure of the LD, holding many layers in common with the LD, and also, the holes flow only into a predetermined part by forming an additional layer for restricting the flow of holes. Thus, the size of the compound semiconductor device can be minimized and a flat topography can be obtained while the threshold current can be lowered by restricting the flow of holes in the LD.

Abstract: The invention relates to a semiconductor arrangement used in particular for the manufacture of infrared-emitting diodes. A first Si-doped GaAlAs layer containing an n-conductivity zone and a p-conductivity zone is deposited onto an n-doped GaAs semiconductor substrate. The Al content decreases continuously over the thickness of the layer. A second GaAlAs layer is deposited on the p-conductivity first zone of the first GaAlAs layer. The Al concentration of the second layer at the barrier surface with the first layer is greater than the Al concentration of the first GaAlAs layer at the barrier surface with the substrate and decreases continuously with the thickness of the second layer. The curve of the Al concentrations in the two epitaxial layers permits a light guiding effect so that the emitted radiation can, unlike conventional GaAlAs diodes, be output preferably onto those sides of the semiconductor array oriented vertically or perpendicularly to the substrate.

Abstract: A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect.

Abstract: A light emitting diode is epitaxially grown on a semiconductor substrate. A lower cladding layer is grown on the substrate and doped to have n-type conductivity. An active layer is deposited on the lower cladding layer, and a p-type upper cladding layer is deposited on the active layer. A relatively thin lower window layer is then deposited on the upper cladding layer, and doped with a first p-type dopant material. A relatively thick upper window layer is then deposited on the lower window layer, and doped with a different p-type dopant material. The layer with a dopant different from the principal portion of the window serves to limit diffusion of dopant through the active layer. The dopant in the diffusion limiting layer can diffuse in both directions, thereby reducing the driving force of diffusion.