Abstract: A gate contact to a field effect transistor is opened over the source/drain region by forming polysilicon plugs between the gate structure, which has a nitride top layer, and the field oxide regions. The contacts are formed by oxidizing and etching the gate structure and the polysilicon plugs. An oxide layer may be deposited prior to the etching. The latter step opens a gate contact but does not expose the silicon in the plug because the different oxidation rates of the polysilicon plug and the material on top of the gate structure create oxide layers having different thicknesses. The nitride is now removed and contacts formed to the gate structure.

Abstract: The propagation of very high frequency signals, e.g., 8 to 10 GHz, via a path printed on a printed wiring board is enhanced by arranging the path so that it simulates a high-quality transmission path at very high frequencies. The path comprises a conventional lead and a series of microstrips, in which the design of the microstrips is optimized to (a) minimize insertion loss and group delay distortion, (b) maximize return loss, and (c) minimize pulse distortion.

Abstract: An organic laser according to the invention comprises an electrically pumped source of incoherent radiation with organic active region, and further comprises a waveguide structure that receives the incoherent radiation. The core of the waveguide comprises organic material that absorbs the incoherent radiation and emits coherent radiation of longer wavelength. The laser forms a unitary structure, with the source of incoherent radiation being close to the waveguide core, exemplarily less than 10.lambda. from the core, where .lambda. is the laser wavelength. Exemplarily the laser is embodied in a planar waveguide laser, in a microdisk laser, or in a laser comprising a photonic bandgap structure.

Abstract: A radio communication device, suitable for use in a portable computer, is capable of operating at any one of a set of common frequencies which are legally permissible in all countries (or a set of countries) and at any frequency on which it detects that a transmission of its own type is being used for a transmission from another device. Thus, users can legally operate the device in different countries, while manufacturers can obtain certification for use in those countries. If the user attempts to select a frequency which is not one of the common frequencies nor detected by transmission, an indication that such frequency is not available is provided to the user.

Abstract: The specification describes a refractive lens for focusing cold neutrons. It comprises a plurality of concave lens elements made from materials with low neutron absorption.

Abstract: According to one aspect of the invention, a magnetorheological fluid (MRF) damping device includes two concentric coils or groups of coils arranged to produce respective magnetic fields that mutually cancel substantially everywhere but within the gap between them. The rheological properties of the MRF are magnetically controlled within this gap. According to a second aspect of the invention, the piston rod of a MRF damper or other viscous fluid damper communicates its motion to a hollow, capped cylinder. Damping fluid within this cylinder communicates via a narrow channel with damping fluid outside of this cylinder. When the piston rod undergoes motions directed so as to expel fluid from the interior of the cylinder, resistance within the narrow channel causes pressure to build up within the cylinder, but prevents any substantial amount of pressure from building up without the cylinder, thus isolating sealing devices from the highest resistive forces generated within the damping fluid.

Abstract: A Multi-Code (MC) Code Division Multiple Access (CDMA) receiver receives N (where N>1) encoded signal channels over multiple air signal paths. The MC-CDMA receiver receives and demodulates the N encoded signal channels into N signal samples and includes a common circuit for time-sharing an accumulator, for accumulating the N signal samples, among a plurality of second correlators. Each of the plurality of second correlator means utilizes the time-shared accumulator to accumulate samples from each of the N signals which are then decoded into an associated one of the N signal channels.

Abstract: A dense waveguide division multiplexer (DWDM) is integrated on a single chip with a plurality of tunable attenuators that are connected in series to the output waveguides of the DWDM in order to equalize the power level on the output waveguides. In the preferred embodiment, the attenuators are thermo-optic Mach-Zehnder interferometer (TMZs) with a tunable range of 0 to 6 dB and a response time of approximately 1-10 milliseconds (ms). A heat sink is attached to the back of the chip to dissipate the heat from the TMZs and to reduce thermal crosstalk. In order to achieve a 3 dB loss on one of the output waveguides via the corresponding TMZ attenuator, approximately 0.25 W is required. In an alternative embodiment, the attenuators are variable stress Mach-Zehnder interferometers (VSMZs).

Abstract: A single-mode stabilized laser comprises a laser cavity having a round trip time .tau..sub.r and a linewidth enhancement parameter .alpha.; and a frequency routing device formed in the laser cavity comprising controllable frequency selective pathways such that selective gating of the frequency selective pathways causes selected lasing frequencies to be supported in the laser cavity separated by a frequency spacing .DELTA.F.sub.C, .DELTA.F.sub.C =1/.tau..sub.r. The frequency routing device has an optical grating having unequal length waveguides to form paths. The optical grating has arms, a time delay .tau..sub.f between the longest path and the shortest path, and a grating bandwidth .DELTA.F.sub.F, .DELTA.F.sub.F =1/.tau..sub.f, at least one of (1) .alpha. and (2) .tau..sub.r and .tau..sub.f having sufficient value to stabilize the laser in single-mode operation.

Abstract: A process for device fabrication and resist materials that are used in the process are disclosed. The resist material contains a polymer in combination with a dissolution inhibitor and a photoacid generator (PAG). The dissolution inhibitor is the condensation reaction product of a saturated polycyclic hydrocarbon compound with at least one hydroxy (OH) substituent and a difunctional saturated linear, branched, or cyclic hydrocarbon compound wherein the functional groups are either carboxylic acid or carboxylic acid chloride groups. The condensation product has at least two polycylic moieties. The polymer optionally has acid labile groups pendant thereto which significantly decrease the solubility of the polymer in a solution of aqueous base. A film of the resist material is formed on a substrate and exposed to delineating radiation.

Abstract: The present invention provides an optical detection system for detecting defects in an optical fiber. The system comprises a light source for projecting a beam of light onto the coating layer of an optical fiber. An optical detector positioned adjacent the optical fiber receives a first light ray reflected at the interface of the air and the coating layer as the light enters the coating layer surrounding the optical fiber and a second light ray reflected at the interface of the air and the coating layer as the light exits the coating layer after passing through the optical fiber. When a defect, such as an airline, for example, is present in the optical fiber, a third light ray is reflected by the defect and is detected by the optical detector. A signal processor is electrically coupled to the optical detector for receiving an output signal from the optical detector and for processing the output signal to determine whether or not one or more defects have been detected.

Abstract: A self aligned contact to the substrate in the region between two gate electrodes is formed by depositing a conformal dielectric layer and patterning to form a contact window. The conductive elements of the gate electrode are not contacted because of etch rate differentials between the conformal dielectric and the insulating elements of the gate structure.

Abstract: A Wavelength-Division-Multiplexed (WDM) network provides delivery of both switched services and broadcast analog video over optical facilities through an intermediate optical apparatus (e.g., Passive Optical Network (PON)) splitter to a plurality of remote optical apparatuses (e.g., optical-network units (ONUs)). The broadcast signal is provided to only a selected ONU, together with the switched service signal for that selected ONU, the selected ONU then distributes the broadcast signal to other ONUs over a separate distribution facility interconnecting the ONUs.

Abstract: There is disclosed, an optical subassembly includes a platform on which a laser and photodiode are mounted. The laser has a rear facet through which passes a small portion of the light emitted by the laser. The photodiode is mounted on the surface of the platform with a light admitting facet for receiving a portion of the light emitted from the rear facet of the laser being substantially perpendicular to the light emitting facet of the laser. The surface of the platform may include a channel. The channel may be tapered from a narrower end near the laser to a wider end near the photodiode, and may be coated with a light-reflective material.

Abstract: The present invention is directed to a process for device fabrication in which a pattern is transferred from a photoresist mask into an underlying layer of silicon dioxide. A plasma containing a fluorocarbon gas is used to etch the pattern into the underlying silicon dioxide layer. The plasma is monitored using optical emission spectroscopy to effect control of the etch process. The optical emission is monitored at select wavelengths. To control the process based on an observation of photoresist etch rate, two wavelengths are monitored. One is associated with a species that is produced by the interaction between the photoresist and the plasma, and one is associated with a species related to the plasma intensity.

Abstract: A processing system comprising a plurality of processors and a plurality of memories, wherein each processor is connected to a memory by a primary bus. When one processor needs to access another processor's memory, it requests access to that particular memory. A bus control monitors memory transactions and causes the processor for this target memory to relinquish the memory. The bus controller then configures a transfer bus and forwards the memory access command to the target memory such that the processor can then access its target memory in addition to its own memory. This configuration remains stable until any processor requests a memory outside of the current configuration or the processor associated with the target memory requests its own memory again. Advantageously, the bus control uses an arbitration table which provides equitable access to all memories.

Abstract: In a pulsed Fabry-Perot laser, such as a Q-switched laser or a mode-locked laser, one of the resonator reflectors comprises a waveguide loop coupled to the gain medium via a polarization splitter/combiner. In one embodiment, only a switchable isolator is located in the loop, thereby significantly reducing insertion loss.

Abstract: A buck switching DC-to-DC regulator having a resistor and capacitor in combination across the storage inductor to measure output current and voltage. The resistor connects to the input of the inductor and the capacitor to the output of the inductor. The junction of the resistor and capacitor connects to an error amplifier for controlling the switching regulator. The regulator may be paralleled for more output current by connecting the outputs together and providing a common reference voltage to all the regulators.

Abstract: An asymmetrical half-bridge converter, a method of operating the same and a power supply that incorporates either the converter or the method.

Abstract: A method for determining the endpoint of a plasma etch process is disclosed. The endpoint of the plasma etch process is determined using an acoustic cell attached to an exhaust port on a reaction chamber of a plasma reactor. At least a portion of the gas from the reaction chamber flows into the acoustic cell during the plasma etch process. Acoustic signals are periodically transmitted through the gas flowing in the acoustic cell and a first velocity for the acoustic signals associated with etching a first material layer formed on a substrate is determined. Thereafter, the endpoint of the plasma etch step is determined when the first velocity changes to a second velocity associated with etching the first material layer through its thickness to its interface with an underlying material layer. The gas from the reaction chamber optionally flows through a compressor prior to flowing into the acoustic cell. The compressor increases the pressure of the gas that flows into the acoustic cell.