Abstract: The specification describes rare earth doped fiber amplifier devices for operation in the extended L-band, i.e. at wavelengths from 1565 nm to above 1610 nm. High efficiency and flat gain spectra are obtained using a high silica based fiber codoped with Er, Al, Ge, and P and an NA of at least 0.15.

Abstract: The specification describes an IC test apparatus having a test bed with sockets adapted to engage arrays of I/O solder balls/bumps on the IC chip. In one embodiment the sockets are provided with through holes to interconnect the solder bumps to the next board level with minimum electrical path length thereby reducing parasitic capacitive coupling. In another embodiment the sockets in the test bed are formed by intersecting V-grooves. If pairs of intersecting V-grooves are used, pyramid shaped features are produced at the bottom of each socket. Both the sharp edges formed by the intersecting V-grooves and the pyramid provide contact enhancement between the solder bumps and the test bed. The test bed can be made as a universal blank for a given solder bump pitch. The desired test circuit is formed at the next board level.

Abstract: The specification describes an optical transmission system for high speed, high capacity digital pulse transmission, i.e. at least 10 Gb/s at a duty cycle of at least 10%, which uses transmission fiber with a dispersion value greater than 20 ps/(nm-km) or more negative than −5 ps/(nm-km). The system operates in the pseudo-linear transmission mode (PLTM). In the PLTM it was discovered that pulse distortion decreases, i.e. eye closure penalty actually decreases, as the dispersion value increases. System performance actually improves by increasing the value of absolute dispersion of the transmission fiber.

Abstract: The specification describes an optical modulator implemented with an MSK format. The modulator creates two separate pulse streams (one pulse stream comprising the odd bits and the other comprising the even bits of the data stream) using a 1-by-2 pulse generator. The modulator then uses electrooptic phase modulators to encode the odd and even numbered bits separately, and a 50/50 coupler to remix them.

Abstract: The specification describes techniques for isolating noisy subcircuits in integrated analog/digital devices. Isolation is obtained using a modification of triple well isolation wherein the deep isolation implant is restricted to the digital circuits only to prevent noise from the digital circuits from propagating to the analog sections through the buried implant. Resistor sections are also separated from the buried isolation implant.

Abstract: The specification describes a technique for evaluating optical fiber splices. The essence of the technique involves detecting thermal power emanating from the fiber splice as the result of absorption of the light carried by the fiber. The technique is particularly suited for cladding pumped lasers wherein the splicing operation may introduce excessive absorption of pump laser radiation and excessive heating at the splice locale.

Abstract: The specification describes a water blocking tape for an optical fiber cable wherein the optical fibers in the cable are wrapped with a synthetic fibrous non-woven tape coated with a superabsorbent polymer powder coating. The particles in the powder are ultra-fine, i.e. have less than 10% weight fraction over 250 microns in diameter, and less than 2% weight fraction over 300 microns in diameter. Controlling the particle size within this small range is found to reduce microbending losses in the optical fiber.

Abstract: Finishing the end of a plastic optical fiber by a device having a semi-rigid or rigid base, a solvent liner for absorbing and holding a solvent, and a re-attachable pull-off cover for keeping the solvent from evaporating when not in use. To polish the end of a plastic optical fiber, the cover is peeled off, the end of the optical fiber is contacted with the solvent liner such that solvent is transferred to the end of the optical fiber, the cover may be reapplied (using a pressure sensitive adhesive integral to either the bottom of the peel-off cover or the top of the liner), the excessive solvent, if any, is removed by using an appropriate swab, and the end of the plastic optical fiber is allowed to return to its normal state. The solvent temporarily dissolves the surface layer of the end of the optical fiber. The resulting surface tension automatically polishes the end of the optical fiber.

Abstract: The specification describes a method and apparatus for electron beam lithography wherein a Wehnelt electron gun is modified to improve the uniformity of the electron beam. The bias on the Wehnelt aperture is reversed from the conventional bias so that it is biased positively with respect to the cathode. The Wehnelt opening is tapered with a disk emitter inserted into the taper. The result of these modifications is an electron beam output with low brightness which is highly uniform over the beam cross section.

Abstract: The specification describes techniques for wire bonding gold wires to copper metallization in semiconductor integrated circuits. A barrier layer is formed on the copper, and an aluminum bonding pad is formed on the barrier layer. Gold wire is then thermocompression bonded to the aluminum pad.

Abstract: The specification describes interconnection techniques for interconnecting large arrays of micromechanical devices on a silicon platform. Interconnections are routed through vias extending through the thickness of the substrate. The vias are formed by etching holes through the silicon wafer, depositing an insulating layer on the sidewalls of the holes, depositing a barrier layer on the insulating layer, electrolytically depositing a metal selected from the group consisting of copper and nickel to form via plugs in the holes, and depositing another barrier layer over the via plugs. It is found that electrolytic deposition will successfully plug the holes even when the aspect ratio of the through holes is greater than four and the hole diameter less than 100 microns.

Abstract: The specification describes a thin film transistor device in which the semiconductor layer is a fluorene oligomer having a molecular weight of less than 2000, and comprising from 1 to 10 fluorene ring units. These oligomers can be deposited by simple evaporation to give desirable semiconductor properties, e.g. high mobility.

Abstract: The specification describes stepped etalon structures and techniques for their fabrication. The preferred etalon material is LiCaAlF6, which is not efficiently processed using reactive ion etching. The approach of the invention is to produce the steps on the etalon by depositing a blanket layer of step material that is effectively etched by RIE, masking a portion of the step material, and etching the masked blanket layer using the LiCaAlF6 substrate as an etch stop. These process steps may be repeated to form multiple steps on the etalon. Etalon structures with steps on both major surfaces are described, as well as etalon structures with steps having differing areas. In the latter case a difference in amplitude in the output signal from a single detector can be used to identify the step that is resonating.

Abstract: A sol-gel process for fabricating bulk, germanium-doped silica bodies useful for a variety of applications, including core rods, substrate tubes, immediate overcladding, pumped fiber lasers, and planar waveguides, is provided. The process involves the steps of providing a dispersion of silica particles in an aqueous quaternary ammonium germanate solution—typically tetramethylammonium germanate, gelling the dispersion to provide a gel body, and drying, heat treating, and sintering the body to provide the germanium-doped silica glass.

Abstract: The specification describes an alignment and attachment process for coupling optical components, such as lasers and photodiodes, to fiber pigtails. The alignment function is shared between two separate pieces of equipment, an alignment tool, and an alignment/attachment tool. Throughput for the alignment/attachment tool, typically an expensive tool, is increased by performing preliminary alignments using the less expensive alignment tool. The preliminary alignment generates coordinates for the position of the optical axis in optical components. These coordinates are transferred to the alignment/attachment tool thus reducing the portion of the time budget in the alignment/attachment apparatus that needs to be devoted to the alignment function. Thus at least a part of the time consuming alignment operations are done in parallel with the alignment/attachment process.

Abstract: The specification describes a high density IC BGA package in which one or more IC chips are wire bonded to a BGA substrate in a conventional fashion and the BGA substrate is solder ball bonded to a printed wiring board. The standoff between the BGA substrate and the printed wiring board to which it is attached provides a BGA gap which, according to the invention, accommodates one or more IC chips flip-chip bonded to the underside of the BGA substrate. The recognition that state of the art IC chips, especially chips that are thinned, can easily fit into the BGA gap makes practical this efficient use of the BGA gap. The approach of the invention also marries wire bond technology with high packing density flip-chip assembly to produce a low cost, high reliability, state of the art IC package.

Abstract: The specification describes packaging assemblies for micro-electronic machined mechanical systems (MEMS). The MEMS devices in these package assemblies are based on silicon MEMS devices on a silicon support and the MEMS devices and the silicon support are mechanically isolated from foreign materials. Foreign materials pose the potential for differential thermal expansion that deleteriously affects optical alignment in the MEMS devices. In a preferred embodiment the MEMS devices are enclosed in an all-silicon chamber. Mechanical isolation is also aided by using a pin contact array for interconnecting the silicon support substrate for the MEMS devices to the next interconnect level. The use of the pin contact array also allows the MEMS devices to be easily demountable for replacement or repair.

Abstract: The specification describes processes for the manufacture of glass ferrules for optical fiber connectors wherein the glass ferrules have a composition comprising silicon oxide, alkali metal oxide, and aluminum oxide to which is added 1-35% of lead oxide.

Abstract: The outside coating of dual coated optical fibers is improved by the addition of a filler to increase the microbending resistance of the optical fiber. The coating is improved by the addition of very small clay platelets, with the platelets aligned along the fiber axis. It is found that standard polymer coatings can be loaded with enough filler to enhance the mechanical properties, while the particulates are small enough to be essentially transparent to the UV curing radiation.

Abstract: Integrated circuit devices are formed in a substrate wafer using selective epitaxial growth (SEG). Non-uniform epitaxial wafer thickness results when the distribution of SEG regions across the surface of the wafer is non-uniform, resulting in loading effects during the growth process. Loading effects are minimized according to the invention by adding passive SEG regions thereby giving a relatively even distribution of SEG growth regions on the wafer. The passive regions remain unprocessed in the finished IC device.