Abstract: A vertical cavity surface emitting laser emitting at about 1.3 microns while being optically pumped by a vertical cavity surface emitting laser emitting at about 810 nanometers characterized in that the resonant cavities of the two lasers are coupled to increase the effectiveness of the pumping light to stimulate emission from the gain medium of the long-wavelength medium. The two lasers are formed in a multilayer stack of which all the layers are epitaxial except for the layers at the top of the stack that serve as a broad band output mirror and the upper bounding of the long wavelength laser.

Abstract: An electrooptic probe for measuring the voltage at regions of an ultra fast device under test includes a standard gallium arsenide substrate that includes on a front surface a film of LT GaAs whose surface includes a conductive stripe that includes first and second portions separated by a gap, the first portion for contacting the region under test, and the second portion for connection to a measuring instrument. The probe is irradiated with a pulsed beam of light, advantageously from a mode-locked femtosecond laser focused at the gap in the stripe and of appropriate two photons, for making conducting by two-photon absorption the region of the film underlying the gap. Preferably the beam irradiates the back surface of the probe to pass through its substrate to reach the gap. Alternatively the beam can irradiate the back surface of the device under test to reach the gap.

Abstract: A method for forming a field effect vertical bipolar transistor that includes a semiconductive body that has at its top surface a plurality of emitter zones of one conductivity type, each surrounded by a base zone of the opposite conductivity type, and gate electrodes for creating a channel at the surface through the base zone into the bulk inner portion of the one conduction type and at a bottom surface a collector zone that includes a collector electrode overlying a collector layer of the opposite conduction type overlying a field stop layer heavily doped of the opposite conduction type overlying the inner portion lightly doped of the one conduction type. Each of the collector layer and the field stop layer is less than 2 microns in thickness and the collector layer is used to inject minority carriers into the inner zone when appropriately biased.

Abstract: The invention relates to a field effect-controllable semiconductor component of vertical or lateral design i.e. MOSFETs and IGBTs. In this case, depletion zones and complementary depletion zones of opposite conduction types are introduced in the source-drain load path, in the semiconductor body, i.e. in the inner zone in the case of vertical components and in the drift zone in the case of lateral components, the concentration of the regions doped by the first conduction type corresponding approximately to the concentration of the regions doped by the second conduction type.

Abstract: A process for producing an epitaxial layer with laterally varying doping includes the following steps: (a) applying a patterned insulator layer to a semiconductor body; (b) growing a first epitaxial layer on the semiconductor body and the patterned insulator layer so that monocrystalline regions are formed over the semiconductor body and polycrystalline regions are formed over the patterned insulator layer, the angle of inclination (&agr;) of the interface between the monocrystalline regions and the polycrystalline regions depending on the grain size of the polycrystalline regions; (c) removing the polycrystalline regions and the insulator layer, and (d) growing a second epitaxial layer which, together with the monocrystalline regions of the first epitaxial layer, forms the epitaxial layer.

Abstract: Optical components that are designed to be coupled together in modular fashion to form an optical network. The components are shaped so that a plurality of components can be coupled together to form a light cube. The components are provided with mating means to permit easy coupling. The preferred form of component is a right-angled triangular prism that can be coupled together with a similar prism to form a cube.

Abstract: A switching network that utilizes at least three degrees of freedom, time, wavelength and space. In one embodiment that involves point-to-point switching, each space channel between an input and an output is assigned a time slot and wavelength coordinate characteristic of the output and the input transmitter and output receiver are tuned to the appropriate time and wavelength coordinates and selective switching is used to complete the space channel between the input and output. In another embodiment for generalized switching, each input channel is assigned a set of space, time slot and wavelength coordinates and an input signal is broadcast to all of the outputs which selectively makes connection to those inputs with an appropriate set of coordinates.

Abstract: Plasma etching apparatus for use in the manufacture of integrated circuit devices utilizes a one-piece director at an input of a process chamber that includes a sleeve portion and a bell jar portion. The director directs incoming process gas in the sleeve portion radially before the gas flows past electrodes used to establish a radio frequency discharge that ionizes the process gas. The one-piece director is clamped between the cap and the sleeve portion of the process chamber to eliminate the need for screws.

Abstract: A method for finding a match between a pattern of data of relatively small size in a base of related data or relatively large size in the presence of occlusions which are gaps or noise that obscure portions, either of the pattern or of the base. The method involves masking out occluded points in both the base data and the pattern so that correlation can be computed only at those points that are not occluded.

Abstract: A computer technique for bipartite matching of objects of one subset with objects of a different subset where multiple choices are permitted. A bipartite graph is formed in which the objects form nodes and the edges connecting pairs of nodes represent costs of matching the nodes connected. The original tour or graph is decomposed into a plurality of quasi-convex subtours or subgraphs and the minimum cost match of each subtour is found and the union of all such matches of the subtours is used as the desired match.

Abstract: A low energy electron beam lithography system uses an 2 KeV electron beam of about three microamperes, a mask formed from a monocrystalline silicon wafer with a membrane thinned to about 0.5 micron, and spaced from an electron-beam sensitive resist-coated substrate about 50 microns and with the thickness of the resist of about 0.1 micron.

Abstract: A number of layered vanadium oxide crystalline compositions are prepared by simple hydrothermal reactions. Generally, the compositions comprise parallel layers of mixed valence vanadium oxides with guest cations intercalated between the layers. The guest cations may comprise metal coordination complexes with bidentate ligands, monomeric ammonium or diammonium cations, or mixtures of alkali metal cations with monomeric ammonium cation or diammonium cations.

Abstract: A computer system that includes a plurality of processing elements for parallel computation utilizes a free-space optical network for communication between the processing elements. Such a network employs an optoelectronic switch that includes a binary H-type tree for routing signals to selected ones of an array of lasers. Hybrid repeaters are included in the optical paths to generate output optical beams colinear that are with incident input beams.

Abstract: A heterojunction is formed between a pair of layers of different semiconductive materials whose work function difference produces a large band offset at the heterojunction. Donor or acceptor atoms are included in one regions that when photoexcited produce free charge carriers but leave behind charged centers that keep the photoexcited carriers localized. The large barrier at the heterojunction limits recombination of the free charge carriers and the charged centers and persistent photoconductivity results. This effect is used to form light operated switches. An illustrative example uses a layer of high purity gallium arsenide forming a heterojunction with a gallium-doped layer of zinc selenide.

Abstract: In a supercomputer that employs a large number of processors operating in parallel, groups of processors are assembled in clusters. Each processor in a cluster is provided with an array of lasers, a different one targeted for a particular detector associated with a specific processor of a different cluster. The detectors associated with the processors in the different cluster are assembled into an array of detectors. A processor wishing to communicate with a processor in a different cluster excites the laser in its associated array that is targeted to the detector of the processor with which it intends to communicate. The patterns of light of the various laser arrays are superimposed into one pattern focused on the detector array by means of an optical tunnel and a spherical lens.

Abstract: A point-to-point optical network for interconnecting processing elements uses a two-dimensional array of chips, each of which includes a two-dimensional array of lasers that are used to target a two-dimensional array of photodetectors. A two-dimensional array of lenslets together with a spherical lens are used to focus light from a laser in the j, k position in any one of the laser arrays in any one of the chips on the particular photodetector in the j,k position in the photodetector array.

Abstract: A computer-implemented process for determining a ranked set of solutions to a bipartite graph matching problem, such is involved in multi-target tracking, maximum flow matching, or data association in matching elements of a first set to elements of a second set to minimize the cost of the association. A feature of the process is a partitioning into subproblems such that the most probable solutions are in the smaller subproblems and the computation begins by solving the smallest subproblem in the search for the best solution.

Abstract: A new dynamic process for test sequence compaction and test cycle reduction that identifies bottlenecks that prevent vector compaction and test cycle reduction for test sequences generated initially and generates subsequent test sequences with the aim of eliminating bottlenecks of the initially generated test sequences. To apply the process to sequential circuits, a sliding anchor frame technique is used that involves specifying the unspecified bits of a partially specified test sequence to detect other faults.

Abstract: A multimedia communications and computer platform that can serve as a network interface card combined with an internal distribution network for a full range of user terminal devices. It includes an interconnection network module that serves to route all incoming and outgoing information by way of high speed buses with value added features for communication protocol acceleration. In particular, attached to the different ports of the network are an ATM module, a communications processor, a media processor and a variety of terminal devices. By migrating processing intensive functions of network protocol termination, media stream distribution and media stream adaptation into the network interface card, there are avoided the bottlenecks of the traditional CPU centric approach to ATM systems.

Abstract: A number of layered vanadium oxide crystalline compositions are prepared by simple hydrothermal reactions. Generally, the compositions comprise parallel layers of mixed valence vanadium oxides with guest cations intercalated between the layers. The guest cations may comprise metal coordination complexes with bidentate ligands, monomeric ammonium or diammonium cations, or mixtures of alkali metal cations with monomeric ammonium cation or diammonium cations.