Abstract: Apparatus for monitoring channel performance in Dense Wavelength Division Multiplexed (DWDM) optical networks, including a tunable optical channel selection filter and a tunable optical notch filter.

Abstract: An optoelectronic assembly (300) includes a laser (102) for emitting light along a main optical path. Beam splitters (110, 114) split a proportion of light from the main optical path and the split light is guided by optical light guides (310) to a photodiode array (302). The light guides (310) are mouldable and substantially rigid and can be co fabricated as a single assembly including fiducials to facilitate positioning on a substrate (124) of the assembly (300). By having the array (302) adjacent the periphery of the substrate (124), wirebonds (308) need only be provided directly from the array (302) to a feed-through (130), and electrical tracks on the substrate and ceramic blocks for mounting the photodiodes are eliminated, as is individual placement of the ceramic blocks on the substrate.

Abstract: An apparatus for converting an input optical signal to an electrical signal. The input optical signal is characterized by a modulation frequency and a modulation wavelength. The apparatus includes a photoconductive switch that is coupled to a photodetector by a common electrode. The photoconductive switch samples the output of the photodetector and is actuated by a switch light signal. The photoconductive switch and the photodetector are arranged such that the switch light signal does not interfere with the optical signal at locations proximate to the electrode and the electrode has a length that is less 0.5 mm.

Abstract: An adapter for attaching a connector having a plurality of pads for interfacing with a device under test. The adapter comprises a carrier having a plurality of voids formed therein in a pattern matching connections on the connector, said voids traversing from a first surface to a second surface of the carrier. At least one electrical component is embedded in at least one void, the at least one electrical component forms a first adapter pad on the first surface of the carrier and a second adapter pad on the second surface of the carrier. When the adapter is interposed between the connector and the device under test the electrical component becomes part of the circuit of the device under test and the connector.

Abstract: Fiber optic alignment methods and apparatus in accordance with the present invention first identify a target beam width incidence on an end of an optical element. The end of the optical element is placed into a beam of light at an axial location relative to the beam of light. The end of the optical element is subsequently moved transversally (perpendicular) to the beam of light until a position of maximum optical power, as measured through the optical element, is identified. A beam width of the beam of light is measured at that axial location. The movement and measurement sequence is repeated at multiple axial locations relative to the beam of light. Linear regression, or an equivalent approach is used, to predict an axial location relative to the beam of light with the target beam width. The end of the optical element is then moved to the axial location with the target beam width.

Abstract: A transistor and method for making the same are disclosed. The transistor is constructed from a collector layer, a base layer, and an emitter layer in a stacked arrangement. The emitter layer is etched to form a mesa on an etched surface, the mesa having a top surface that includes a portion of the emitter layer and an emitter contact and sides joining the top surface with the etched surface. First and second protective layers are then deposited over the emitter contact and etched surface and the portions of these layers that overlie the etched surface are removed. The first protective layer is then preferentially etched thereby undercutting a portion of the first protective layer on the sides of the mesa and creating an overhanging portion of the second protective layer that is utilized to align the deposition of the base contacts.

Abstract: Controlling or stabilising the lasing wavelength of a source of laser radiation, wherein the source of laser radiation comprises a semiconductor material laser, a substrate to which the laser is mounted, a resonant optical cavity within the semiconductor material, the cavity having an active medium for generating laser radiation and one or more gaps in the semiconductor material within the cavity, wherein the substrate is deformable by the application of a mechanical stress to vary the size of the gap(s) in order to change the optical size of the gap(s) and hence to vary the wavelength of laser radiation generated by the semiconductor laser.

Abstract: A laser driver circuit includes a pair of transistors having base electrodes respectively coupled to a differential input signal. The respective collector electrodes are coupled to a first power supply rail and the respective emitter electrodes are coupled to a laser diode via respective impedances and to respective controllable current sources to provide an average modulation voltage at the more positive of the emitter electrodes. By having the transistors in an emitter follower configuration, rather than the usual collector open collector configuration, the problem of mismatch between the output impedance of the transistors and the input impedance of the laser diode is reduced.

Abstract: A method for forming a wafer package includes forming a die structure, wherein the die structure includes a first wafer, a device mounted on the first wafer, a second wafer mounted atop the first wafer with a first seal ring around the device and a second seal ring around a via contact. The method further includes forming a trench in the second wafer around the first seal ring, filling the trench and the via contact with a sealing agent, patterning a topside of the second wafer to removed the excessive sealing agent and to expose a contact pad of the via contact, and singulating a die around the first seal ring.

Abstract: A dual path analog-to-digital conversion method and system. The system includes a first and second circuits. The first and second circuits each convert an input analog signal into digital signals at differing sample rates. The circuit having the slower sampling rate aliases frequency components of the input analog signal that are higher than half that sampling rate. Frequency components causing the aliasing in the slower sampling circuit are replicated from the faster sampling circuit at the appropriate amplitude, folded into the aliased frequency, and subtracted from the output of the slower sampling circuit. The outputs of both sampling circuits are then merged. These techniques extend the bandwidth of the slower conversion system without degrading the low-frequency accuracy of the slower conversion system.

Abstract: An electrostatic discharge (ESD) structure for use in an integrated circuit (IC). The ESD structure comprises a metallic resistor and a metallic capacitor that are electrically coupled in series to form a resistor-capacitor (RC) component having an appropriate RC time constant. The RC component maintains a level of charge between ground and a shunt node to ensure that, during an ESD event, electrostatic charge on a power supply, VDD, associated with the ESD structure is shunted via a shunt path from said power supply VDD to said ground. By using metal to create the metal resistor and capacitor, charge leakage problems that result from parasitic capacitance associated with using an RC component comprised of either a poly, active, or nwell resistor in combination a diode are eliminated. By eliminating such charge leakage problems, a more reliable RC component, and thus a more reliable RC time constant, are obtained.

Abstract: A method for separating dies on a wafer includes etching channels around the dies on a first side of the wafer, mounting the first side of the wafer to a quartz plate with an UV adhesive, and grinding a second side of the wafer until the channels are exposed on the second side of the wafer. At this point, the dies are separated but held together by the UV adhesive on the quartz plate. The method further includes mounting a second side of the wafer to a tack tape, exposing UV radiation through the quartz plate to the UV adhesive. At this point, the UV adhesive looses its adhesion so the dies are held together by the tack tape. The method further includes dismounting the quartz plate from the first side of the wafer and picking up the individual dies from the tack tape.

Abstract: An efficient way to fabricate the channels and cavities in a LIMMS device is to form them as matching upper and lower portions each created as a patterned layer of thick film dielectric material deposited on a respective upper or lower substrate. The two portions are adhered together by a patterned layer of adhesive, and hermetically sealed around an outer perimeter. The heater resistors are mounted atop the lower layer, thus suspending them away from that substrate and exposing more of their surface area. Vias can be used to route the conductors for the heaters and the switched signal contacts through the lower substrate to cooperate with surface mount techniques using solder balls on an array of contact pads. These vias can be made hermetic by their placement within the patterned layers of dielectric material and by covering their exposed ends with pads of hermetic metal.

Abstract: Optical pulses at a given repetition rate (f) are obtained by modulating an optical signal by means of a Mach-Zehnder modulator. The modulator is driven by means of a driving signal including, in addition to a sinusoidal component at a frequency (f/2) half the repetition rate (f) of the pulses, at least one odd harmonic of the sinusoidal component. Very short optical pulses can thus be generated without giving rise to undesired side effects such as ringing in pulse tails.

Abstract: A Test Station for a memory tester is comprised of one or more Test Sites that are each individually algorithmically controllable, that can each deal with as many as sixty-four channels, and that can be bonded together to form a Multi-Site Test Station of two or more Test Sites. Up to nine Test Sites can be bonded together as a single Multi-Site Test Station. Bonded Test Sites still operate at the highest speeds they were capable of when not bonded. To bring this about it is necessary to implement certain programming conventions and to provide certain housekeeping functions relating to simultaneous starting of separate test programs on the bonded Test Sites, and relating to propagation and synchronization of test program qualifier results among those separate test programs.

Abstract: A switch and production thereof. The switch may be produced by (1) depositing a liquid switching element on a substrate, (2) positioning a channel plate adjacent the substrate, (3) moving the channel plate toward the substrate, the liquid switching element wetting to the channel plate, and a portion of the liquid switching element isolated into at least one waste chamber in the channel plate; and (4) closing the channel plate against the substrate.

Abstract: A gas plasma emission source includes a solid state signal power source coupled to a resonant cavity. In an alternative embodiment of the invention, an atomic emission detector includes a solid state signal power source coupled to a resonant cavity and a spectrographic detector to sense atomic emissions from a gas within the resonant cavity. In yet another embodiment of the invention, a method of sustaining a plasma includes passing a gas through a resonant cavity and exciting the resonant cavity with signal power from a solid state power source to sustain the plasma in the gas. In another embodiment of the invention, a method of using a solid state power source includes passing a gas through a resonant cavity and coupling sufficient signal power from an output of the solid state power source to sustain a plasma in the gas where the sufficient power is less than 300 watts.

Abstract: A surface having specular regions shaped to reflect incident light toward an optical sensor provides an ideal surface to be scanned by an optical mouse. When light is shined upon the surface, the reflections off of the specular regions appear as white points in the image acquired by the optical sensor, which gives the optical sensor the distinguishing characteristics it needs to differentiate between images. Since the specular regions reflect light so well, less light is needed to obtain an image, and power is conserved. The surface appears as a dark background in the image, providing contrast to the light reflecting off the specular regions. To protect the specular regions, an optically transparent coating can be layered on top of the surface. An alternative surface that may be easier to manufacture is a light colored surface dotted with darker colored regions.

Abstract: Array hybridization devices and methods for their use are provided. The subject devices are characterized by having a substantially planar bottom surface, a cover, at least one fluid port and at least one adjustable spacing element for adjusting the spacing between an array and the bottom surface. In using the subject devices, an array is placed on the at least one adjustable spacing element in the chamber and the space between the array and the bottom surface is adjusted by moving the at least one adjustable spacing element. The adjusted array is contacted with at least one biological sample introduced into the chamber. The subject inventions find use in a variety of array-based applications, including nucleic acid array hybridizations.

Abstract: A semiconductor laser having a mesa structure includes active laser layers. The mesa structure is confined by Fe—InP lateral semi-insulating layers. A p blocking layer is interposed between the mesa structure and the lateral semi-insulating layers. Performance at high temperature and linear laser operation are improved. A preferred application is for manufacturing SIBH-DFB lasers for direct modulation in the 10 Gbit/s range.