Abstract:
A method for fabricating an InP diffraction grating for a distributed feedback semiconductor laser includes the steps of applying an electron beam resist on a semiconductor substrate, giving electron beam exposure to the electron beam resist and controlling heights of resist patterns by using fixed electron beam diameters but by varying incident electron doses. The semiconductor substrate is dry-etched. The electron beam exposure is such that the incident electron doses are made larger at a center portion than at portions towards two sides of the diffraction grating. Due to the proximity effect, the resist patterns after development will have a lower height and a narrower width at portions at which the incident electron doses are increased and, conversely, a higher height and a wider width at portions at which the incident electron doses are decreased. In a method of fabricating a distributed feedback laser using a substrate of the InP diffraction grating fabricated as above, the method includes the step of sequentially growing on the substrate a waveguide layer, an active layer and a cladding layer. The method enables to fabricate a low distortion distributed feedback laser for analog modulation having non-uniform diffraction gratings.
Abstract:
A semiconductor light emitting/detecting device has a first doped silicon layer, an intrinsic silicon epitaxial layer formed on the first doped silicon layer, at least one quantum dot embedded within the intrinsic silicon epitaxial layer, and a second doped silicon layer formed on the second intrinsic silicon epitaxial layer.
Abstract:
A process is disclosed of diffusing a zinc dopant into a III-V compound substrate. To avoid degrading the substrate surface the zinc dopant source is provided by coating an organic composition comprised of a zinc organic compound chosen from the group consisting of zinc alcoholates, .beta.-diketonate chelates and carboxylate salts. The composition inludes at least one organic film-forming moiety containing from 5 to 30 carbon atoms.
Abstract:
A semiconductor light emitting device includes a vertical aperture produced at a main surface of a semi-insulating or insulating substrate, a transverse aperture provided in the substrate communicating with the vertical aperture, a conducting semiconductor layer buried in the vertical aperture and the transverse aperture, a groove produced by etching the substrate from the surface thereof until reaching the conducting semiconductor layer at a portion of the transverse aperture, and a light emitting element produced in the groove, and the light emitting region of the element being buried in the groove and connected with the buried conducting semiconductor layer. Accordingly, no pn junction exists at the periphery of the light emitting region, and a semiconductor light emitting element of quite low parasitic capacitance is obtained at high yield. A planar structure in which two electrodes are produced at the same plane is obtained, resulting in ease of integration and enhancement of the integration density.
Abstract:
The disclosure herein pertains to a vapor phase process for the preparation of electroluminescent materials, particularly GaP, doped with isoelectronic impurities, particularly nitrogen, and to electroluminescent devices fabricated therefrom.
Abstract:
This invention relates to a monolithic integrated circuit in a substrate of a first semiconductor material containing electrically insulated islands of other different semiconductor materials. Preferably each of the islands is isolated from the substrate and from each other by an insulating layer of material. Thus an integrated circuit can be manufactured in a single substrate in accordance with the particular needs of the circuit functions required.
Abstract:
AN AVALANCHE PHOTODIODE, PARTICULARLY USEFUL FOR DETECTION OF INFRARED ENERGY IN THE WAVELENGTH REGION FROM 1 TO 2 MICRONS, INCLUDES AN ACTIVE EPITAXIAL LAYER OF A QUATERNARY IIIV ALLOY SUCH AS N-IN-1-YGAYP1-XASX. THE ACTIVE LAYER INTERFACES WITH A SECOND LATTICE MATCHED EPITAXIAL LAYER OF P-TYPE JUNCTION AL TO DEFINE A LATTICE MATCHED P-N JUNCTION THEREBETWEEN WHICH IS REVERSED BIASED, IN USE. THE ACTIVE LAYER HAS A DIRECT BANDGAP ENERGY LESS THAN THE PHOTON ENERGY OF THE INFRARED ENERGY TO BE DECTED FOR ABSORPTION OF THE PHOTONS TO BE DETECTED TO GENERATED ELECTRON-HOLE PAIRS. THE ACTIVE ALYER IS MADE OF A MATERIAL HAVING AN ENERGY DIFFERENCE BETWEEN THE LOWEST CONDUCTION BAND MINIMUM BAND THE NEXT HIGHER CONDUCTION BAND MINIMA EITHER X1 OR L1 WHICH IS GREATER THAN 1.1 TIMER THE DIRECT BANDGAP ENERGY OF THE ACTIVE LAYER, WHEREBY IMPROVED SIGNAL TO NOISE RATIO IS OBTAINED.
Abstract:
A method of fabricating an integrated multicolor organic LED array including providing a negative layer and patterning a plurality of different color LED organic layers, one at a time, on the negative layer to form a plurality of different color LEDs in a plurality of areas of a selected array. A first color LED organic layer is patterned on the negative layer in first areas and to define additional areas for additional LEDs laterally separated from the first color LEDs and a final color LED organic layer is deposited in final areas and on previously patterned layers to form a plurality of final color LEDs. Transparent positive contacts are then formed on the final color LED layer in the first and final areas so as to form positive contacts to the first and the final color LEDs.
Abstract:
Methods of etching optical elements in association with photosensitive elements are described. In some of the arrangements, the optical elements are formed integrally with a substrate containing the photosensitive elements. In other arrangements, an optical element is mounted to a package, or the like, containing the substrate and photosensitive elements. In other arrangements, two or more optical elements are employed, including conventional refractive elements, refractive focusing elements, and refractive beam splitting elements. Utility as solid state image sensors is discussed. Utility for monochromatic and color imaging is discussed.
Abstract:
A light emitting device that comprises an organic LED array containing a plurality of light emitting pixels, the pixels each being located on a common electrically insulative transparent substrate, is characterized in that the transparent support is ultra thin, having a thickness less than the pitch of the pixels. The pixels in the LED array can be arranged in intersecting columns and rows, or they can comprise a line array. A process for forming a light emitting device on an ultra thin transparent substrate comprises the following steps: (a) releasably laminating to an ultra thin electrically insulating transparent substrate a relatively thick rigid temporary support; (b) forming the LED array on the ultra thin substrate; (c) forming on a relatively thick rigid permanent support an electrical conductor patterned in conformity with the first electrode element and the second electrode element on the ultra thin substrate; (d) forming an array of electrically conductive malleable bonding bumps on the patterned electrical conductor located on the permanent support; (e) aligning the first and second electrode elements in correct registration with the patterned electrical conductor; (f) contacting the bonding bumps on the electrical conductor with the first and second electrode elements; (g) forming a physical and electrical connection between the bonding bumps and the first and second electrode elements; and (h) delaminating the temporary support from the ultra thin transparent substrate. Additionally, a transparent and electrically insulative sealant material can be introduced into the space between the ultra thin substrate and the electrical conductor on the permanent support.