Abstract: The present invention relates to a multi-layer dopant barrier and its method of fabrication for use in semiconductor structures. In an illustrative embodiment, the multi-layer dopant barrier is disposed between a first doped layer and a second doped layer. The multi-layer dopant barrier further includes a first dopant blocking layer adjacent the first doped layer and a second dopant blocking layer adjacent the second doped layer. A technique for fabricating the multi layer dopant barrier is disclosed. A first dopant blocking layer is formed at a first temperature, and a second dopant blocking layer is formed at a second temperature over the first barrier layer.

Abstract: The present invention provides an optoelectronic device, a method of manufacture thereof and an integrated optoelectronic system incorporating the same. The optoelectronic device may be a tunable laser that includes a capacitor located over one of the first outer surface or the second outer surface. The outer metal layers of the tunable laser can be used to form a first electrode of the laser, after which a dielectric layer and a second electrode are deposited and patterned to form the laser having a capacitor incorporated thereon.

Abstract: A fiber optic device and a method of assembling the fiber optic device to provide at least four degrees of adjustment for an optical beam transported between an optical fiber and bulk optics in an optical device package. At an opening in the wall of the optical processor package, a washer-like structure allows initially adjustable contact at a flat surface thereof and at a spherically curved surface thereof. One of the surfaces bears against the wall about the opening and the other surface bears against a contact feature of a connecting assembly, typically a pre-assembled collimator assembly, that holds a termination portion of the optical fiber. Translational adjustment is made at the flat surface and tilting adjustment is made at the curved surface before final attachment at both surfaces.

Abstract: A micro-lens array and a method for making are described. The micro-lens array includes a base element and a plurality of lenses formed of an epoxy and including nanoparticles. The micro-lens array is formed from a master micro-lens array, which is placed within a replica micro-lens making assembly. The master micro-lens array is coated with an anti-stiction material prior to having an elastomeric material positioned over it and cured. Removal of the elastomeric material provides a plurality of cavities, which are filled with an epoxy including nanoparticles. Curing of the epoxy finishes the fabrication of the micro-lens array. The lenses of the micro-lens array are formed from a colloidal suspension of nanoparticles and resin.

Abstract: A thermo-optic device and a method for using it are described. The device has a substrate including a pair of waveguides coupled at first and second coupling regions. At the first coupling region, an input signal is split between the two waveguides. Between the coupling regions on one of the waveguides is a demultiplexer, at least one phase shifting device, and a multiplexer. The signal portions recombine at the second coupling region. Heater strips at the first and second coupling regions alter the temperature at the first and second coupling regions, in response to applied control signals, thereby adjusting the insertion loss and dynamic range of the device. A sensor samples an output signal from the substrate and sends a signal to a controller, which controls the phase shifting devices and the heater strip to maintain the output signal within predetermined signal parameters.

Abstract: The present invention provides a method and apparatus for compensating for the age induced wavelength drift in a tunable DBR. In practice, the tuning characteristic (i.e. output wavelength versus tuning current) of a tunable DBR may be characterized before and after factory aging, typically in the form of a burn-in or purge cycle. An aging vector may be constructed in accordance with the ratio of the change in the tuning characteristic associated with a second output wavelength and the change in the tuning characteristic associated with a first output wavelength as a function of the factory aging. In addition, the tuning characteristic associated with transmission at the first output wavelength may be monitored in the field.

Abstract: A broadband impedance matching circuit for use with an optical device such as an electroabsorption optical modulator comprises a microstrip transmission line, including pairs of like-sized open stubs disposed on opposite sides of the transmission line along its length. The number of open stubs, as well as their dimensions and location are chosen to provide for broadband impedance matching (from dc to several GHz) between an external electrical signal source and the optical device.

Abstract: An improved semiconductor laser (distributed feedback or Bragg reflector laser) is disclosed, having reducing wavelength chirping. In a laser having a substrate, an optical waveguide layer disposed on the substrate with a grating region, and a cladding region disposed on the optical waveguide layer, an isolation region is positioned in at least one of the substrate, optical waveguide layer, and cladding layer. The isolation region is comprised of a material adapted to increase the resistivity of the one or more layers in which it is placed to reduce electrical cross-talk and wavelength chirping. Preferably, the isolation region is positioned in at least the cladding layer, which the inventors have found is the greatest contributor of cross-talk and wavelength chirping.

Abstract: The present invention provides an electronic device having superior qualities. The electronic device includes an active region located over a substrate and an undoped layer located over the active region. The electronic device further includes a doped upper cladding layer located over the undoped layer, wherein a diffusion barrier region including aluminum is located between the undoped layer and the doped upper cladding layer. In an exemplary embodiment of the invention, the diffusion barrier region is a diffusion barrier layer or a number of diffusion barrier layers located between a plurality of the undoped layers.

Abstract: A method for decreasing the diffusion of dopant atoms in the active region, as well as the interdiffuision of different types of dopant atoms among adjacent doped regions, of optoelectronic devices is disclosed. The method of the present invention employs a plurality of InAlAs and/or InGaAlAs layers to avoid the direct contact between the dopant atoms and the active region, and between the dopant atoms in adjacent blocking structures of optoelectronic devices. A semi-insulating buried ridge structure, as well as a ridge structure, in which the interdiffusion of different types of dopant atoms is suppressed are also disclosed.

Abstract: An optical receiver having a silicon substrate with a top surface cleaved from a [100] silicon crystallographic plane and a reflector, and a photodetector coupled to the top surface of the silicon substrate, the photodetector being adapted to receive an incoming signal from a fiber.

Abstract: The present invention provides a device, a method of making the device, and a system incorporating the same. In one embodiment, the device includes a substrate that has first and second opposing surfaces and first and second thicknesses, wherein the second thickness is less than the first thickness, and the first surface is substantially planar. The device further includes a conductive trace having an input end and an output end and located over the first surface of the substrate, wherein at least one of the input end or output end is aligned with the second substrate thickness.

Abstract: The present invention is directed toward a monitoring and control system for an optical system. In one aspect of the present invention the system may include an interferometer that splits an input beam into a transmitted portion and a reflected portion. The interferometer introduces a path length difference between at least a segment of the transmitted and reflected portions that recombine to form an output beam having an intensity that varies as a function of wavelength of the input beam.

Abstract: An e-beam deposition method and apparatus uses a metallic target and localized oxygen ambient to produce an oxide film for deposition. A metallic target is first heated, then exposed to a stream of oxide, resulting in the formation of a relatively thin layer of oxide on the metallic target surface. Since the oxide has a higher vapor pressure than the underlying metal, when the target is impinged by an electron-beam current, the oxide will preferentially vaporize and be deflected toward the surface to coated.

Abstract: The invention is a semiconductor optical device and method of fabrication where the device includes an active region with an active layer having a first index of refraction, and a blocking region having a second, lower index of refraction. A semiconductor layer having an index of refraction higher than the blocking region is formed over both the active and blocking regions so that the semiconductor layer is in closer proximity to the active layer in areas not covered by the blocking region so as to decrease the difference between the effective index of refraction in the active region and the effective refractive index of the blocking region. Such devices are particularly useful for pumping optical amplifiers since greater power can be achieved while maintaining single mode emission.

Abstract: The present invention is a method for making planar waveguides. The method comprises the steps of providing a workpiece comprising a layer of material suitable for the wave guide strip; patterning the layer so that the workpiece comprises, a base portion and the at least one protruding portion; forming a cladding layer on the protruding portion; and attaching the cladding layer to a substrate. Depending on the composition of the workpiece, the process may further require removing the base portion to expose the bottom surface of the protruding portion. With this method, a planar waveguide or a planar waveguide amplifier may be fabricated having thickness dimensions greater than 5 &mgr;m, or more preferably, in the range of 10-20 &mgr;m.

Abstract: A mode converter for converting an optical signal from a first propagation mode (e.g., LP01) to a second propagation mode (e.g., LP02). The mode converter includes a first waveguide supporting a first mode of propagation. The mode converter also includes a second waveguide supporting a second mode of propagation. The first and second waveguides each having a group index characteristic, wherein the first group index characteristic is matched with the second group index characteristic such that electromagnetic energy propagating through the first waveguide at the first mode couples to the second waveguide at the second mode.

Abstract: An optical fiber assembly including a ferrule which increases the glass transition temperature of an entire epoxy system resident within the ferrule and a method for suppressing optical instabilities of an optoelectronic package are described. One or more openings are made in a ferrule body to allow reaction gases from the epoxy caused during curing to escape, allowing a greater portion of the epoxy to fully cure, thereby raising the glass transition temperature of the epoxy system.

Abstract: The present invention provides an optoelectronic device that includes an optical active layer formed over a substrate and an active region formed in the optical active layer. The optoelectronic device further includes a P-contact and an N-contact formed over a same side of the substrate and associated with the active region, the N-contact is located within a trench formed in the optical active layer and contacts the substrate within the trench.

Abstract: An optical receiver is formed to include a digitally-controlled preamplifier that is used to adjust the bandwidth of the receiver. A measured bandwidth of the receiver is compared to a desired bandwidth and a digital control signal (such as a voltage, current, or any other appropriate parameter) supplied to the preamplifier is thereafter adjusted (either increased or decreased) to increase/decrease the bandwidth of the receiver to the desired value. A voltage regulator and potentiometer may be used as the digital controller and coupled to the input voltage supply of the preamplifier to provide the needed adjustment in voltage.