Abstract: The specification describes a lithographic technique in which alignment marks are defined in a first semiconductor layer and the alignment marks are then covered with a protective SiO2 layer. After subsequent semiconductor layer growth steps, which selectively deposit on the former semiconductor layer but not on the protective layer, the alignment marks remain undistorted and visible to the exposure tool for subsequent processing.

Abstract: A micromirror array is used to form optical apparatus useful in WDM optical networks. In one embodiment, the micromirror array is used to insert a desired attenuation in individual channels for purposes such as equalization. In another embodiment, the micromirror array is used to form an optical monitor useful as an optical spectrum analyzer.

Abstract: The present invention is an intelligent optical transmitter module that is used to produce optical test signals. The optical transmitter module contains a solid state laser and a microprocessor. The solid state laser produces the test signals which are used to test optical fibers in an optical fiber network. The laser is both monitored by and controlled by the microprocessor. In one embodiment, backface monitoring and optical output coupling power monitoring (using an optical tap) are accomplished within the module in order to more accurately reflect the state of the laser. The microprocessor reads data regarding the performance of the solid state laser which may be output to another control device. The control device utilizes the data from the microprocessor in the analysis of fiber optic loop conditions as well as the laser itself. The microprocessor enables the output levels of the solid state laser to be adjustable by way of a digital to analog converter.

Abstract: A saturable Bragg reflector for use in mode locking a laser comprises a stack alternately of layers of a high index of refraction and layers of a low index of refraction. The layers of high index all have optical thicknesses of about one quarter the operating wavelength of the laser. The layers of low index, except for the pair of uppermost layers, have optical thicknesses of a quarter the operating wavelength but that pair have a thickness of about one eighth of a wavelength. A quantum well is located near the center of the layer of high index between the pair of one eighth wavelength. Such a reflector is used as one end of a resonant cavity that houses a gain medium.

Abstract: The specification describes techniques for applying solder bumps to IC chips. The solder bump sites are first provided with under bump metallization (UBM) for solder bump interconnections to the Al bonding sites on the IC chip. The substrate, i.e. the capping layer of the IC chip, is coated with photoresist and patterned to expose the UBM and a peripheral portion of the capping layer around the UBM. The solder paste is then applied and reflowed to form the solder bump. Since the photoresist hardens and becomes difficult to remove after the reflow step, a sacrificial buffer layer is interposed between the photoresist and the capping layer to facilitate removal of the photoresist without attacking the IC chip surface.

Abstract: A method for uniformly doping a semiconductor surface including non-planar regions. A doped coating material, such as in-situ doped polysilicon or doped glass, is deposited or spread over an etched silicon substrate or wafer. Heat is applied at high temperatures to drive n or p type dopants from the doped coating material into nearby regions of the substrate. In this manner angled or recessed regions of a substrate, such as vertical or angled junction sidewalls in v-groove or trench structures, are uniformly doped.

Abstract: The invention teaches an in-site roller dresser that allows for the profile of the polishing pad to be monitored while the roller is dressed or refurbished. This eliminates the need for destructive testing of the polishing pad. The in-site roller dresser at the same time eliminates the need for machine downtime for polishing pad profile determination since the polishing pad profile is dynamically tested and monitored during polishing operations. In conventional arrangements, the dresser is a disk, in the arrangement of the present invention the dresser is a roller type that can rotate around its axis in either direction. A sensor is provided with the diamond dresser that monitors the surface or profile of the polishing pad. Based on the data obtained by the sensor, the diamond dresser can be adjusted which directly controls the polishing pad refurbishing action provided by the dresser.

Abstract: A microprocessor includes a multiply-accumulate unit (MAU) for performing high-speed signal processing operations. First and second caches provide first and second operands (x, y) directly to the MAU when a multiply-accumulate (MAC) instruction is executed. In addition, a multiplexer is included to select data from either the first and second caches when a normal instruction is executed. A translation look-aside buffer may be included that has page table entries that include additional “reconfigure” and “way” bits to control writing data into the caches. In this manner, the microprocessor may use a conventional n-way set-associative cache to simultaneously access two or more operands.

Abstract: A class of opto-electronic mechanical devices that include a planar optical waveguide having a cladding in which there is carried an evanescent electric field by a light beam traveling along the waveguide and a mechanical micro-element controllably coupled into the evanescent field for varying locally the properties of the waveguide in a wavelength dependent fashion. The devices described include optical switches and WDM add/drop apparatus.

Abstract: An optical switch uses a MEMS device to insert a highly reflective shutter in a gap between a pair of coaxially aligned fibers. When the switch is closed, an input optical signal passes with little loss through the gap. When the switch is open and the shutter is positioned in the gap, an input optical signal incident on the shutter is reflected back into the input fiber. Such light is diverted by an optical circulator into a new path.

Abstract: A simple high speed Real-Time method and apparatus for processing a queue in a network queue server is presented. Long packets at the beginning of the queue are processed while a pointer chains down the queue to find shorter packets. When a shorter packet is found the pointer stops and waits for a timing threshold to be met. When the timing threshold is met the short packet is processed until completion and then work is resumed on the long packet. The method is implemented using a pointer to identify the position in the queue that is currently being processed, a pointer to search for the shorter packets, two registers to hold values of the respective pointers and memory to hold the location of the discontinued packet. An additional register is utilized to hold the incremented cycle processing time, and a final register is used to hold a threshold value for processing a packet. Lastly, a previous pseudo head register is also utilized when the queue is not doubly linked.

Abstract: An improved packet delay estimation method results from an indirect measurement method that employs an estimation method based on sampled lengths of queues and measured traffic. A complex system of queues sharing the same constant rate server and driven by a non-trivial scheduling scheme is split into logical clusters of queues. The method estimates packet delay based on a two-level approximation. On the first level of approximation, effects of the fact that the server is shared by other clusters is approximated by an equivalent reduction of the service rate. On the second level of approximation, individual queue lengths within a cluster are sampled and, based on the knowledge of the scheduling discipline, used to obtain the upper and lower bounds on the occupancy of the equivalent FIFO buffer. Estimate of the delay is found based on the effective buffer occupancy, and the effective service capacity.

Abstract: Apparatus and a method for providing a caller with information about a called party. In one preferred embodiment, the information includes information concerning the charges to be incurred in making a call to the called party. Advantageously, in an environment wherein number portability allows a call which previously was a local call, to become a toll call because the called party has made a geographic move, without changing the called party's telephone number. For wireless service, in those cases in which the caller pays at least a part of the charges, and the charges for a call to a roamer are different if the roamer is locally found than if the roamer is remotely located, this service allows a caller to decide on whether to complete a call, and if the decision is made to complete a call, on what length call to aim for.

Abstract: A micromechanical tilt mirror device that includes a membrane suspended by its ends over a substrate such that a mirror area of the membrane is asymmetrically positioned on the membrane whereby it is tilted when the membrane is deformed by electrostatic forces. This mirror tilt is used to steer an incident light beam in a prescribed direction. The mirror can be supported to provide tilt in either of two orthogonal directions with respect to a rest direction.

Abstract: An optical attenuator for use in optical power regulation uses a shutter to control the insertion loss of a gap in a pair of substantially coaxially aligned waveguides, for example a pair of optical fibers. The shutter is part of a MEMS accuator device and is coupled to the movable one of a pair of spaced plates, the movable plate being movable by a voltage applied between the pair of plates. To regulate the power, a small portion of the optical power is abstracted and used to derive a control voltage that is applied to the optical attenuator for varying the attenuation inserted in the optical wave path.

Abstract: An integrated laser/modulator (“ILM”) operating with reduced chirping is formed on a single semiconductor substrate. A reduction in chirping and any resultant wavelength dispersion is realized by precisely controlling the length of a window region incorporated in the ILM in order to isolate the ILM's active regions from any residual reflections.

Abstract: Testing time of interconnections is reducted by splitting up the collection of connection paths to be tested into two or more groups. A set of test vectors, which is applied to each of the groups concurrently, is arranged to insure that the two adjacent connections that are assigned to different groups are not tested concurrently. The user can select the number of groups, and the number of connection paths within each group (which need not be the same for all groups). The disclosed algorithm increases the number of connection paths that are tested with each concatenated test vector, and consequently the number of required test vectors is reduced.

Abstract: Fraud losses in a communication network are substantially reduced by automatically generating fraud management recommendations in response to suspected fraud and by deriving the recommendations as a function of selected attributes of the fraudulent activity. More specifically, a programmable rules engine automatically generates recommendations based on call-by-call fraud scoring so that the recommendations correspond directly to the type and amount of suspected fraudulent activity. Using telecommunications fraud as an example, an automated fraud management system receives call detail records that have been previously scored to identify potentially fraudulent calls. Fraud scoring estimates the probability of fraud for each call based on the learned behavior of an individual subscriber as well as that of fraud perpetrators. Scoring also provides an indication of the contribution of various elements of the call detail record to the fraud score for that call.

Abstract: A method for transmission of digital information packets over a transmission channel. A transmitter computes a current value of a carrier-sense defer threshold and a transmit power level, based an observed ratios between recent packet transmission successes, recent packet collisions, recent packet deferrals, and an estimate of a path-loss characteristic of the transmission channel. The computed power level and carrier-sense defer threshold are selected to obtain a desired ratio of at least two of future packet success, future packet collisions, or future packet deferrals. The current carrier-sense defer threshold value is used to determine when a carrier signal for another transmitter's digital information packet is present on the transmission channel; transmission is deferred until the channel is determined to be clear of other packets. The packet is then transmitted at the computed power level.

Abstract: An improved waveguide optical amplifier having an optically transparent first cladding layer, an optically transparent film doped with an optically active material, disposed over the first cladding layer, at least one undoped optically transparent film disposed over the doped film and coating etched walls of the doped film, and an optically transparent second cladding layer disposed over the undoped film. At least a portion of the undoped film disposed immediately adjacent the doped film has an index of refraction which is closer to the index of refraction of the doped film, than to the index of refraction of the second cladding layer and preferably equal thereto. The undoped film covers surface imperfections in the etched walls of the doped film, effectively moving them from the doped film/undoped film interface to the undoped film/cladding layer interface thereby reducing scattering of the high-intensity mode field.