Abstract: A redundant configurable VCSEL laser array optical light source which provides for integrating optical communications capabilities into manufacturing processes for a substrate or submount such as a silicon or ceramic substrate, a multi-chip module, a package board, backplane or similar component. Multiple, spatially proximate lasers and photodetectors are provided as part of an optical transmitter or receiver module to simplify assembly of the module, particularly alignment of a laser or photodetector to an optical fiber or waveguide. A feedback loop and control logic select those laser(s) or photodiodes(s) which are most strongly coupled to the transmission medium to produce the best signals. This approach greatly simplifies optical alignment, to improve yield and relax mechanical tolerances, leading to lower assembly costs and higher manufacturing yields.

Abstract: A method of and apparatus (10) for detecting one or more defects (130) in a plurality of chips (110) on a wafer (40). The method comprises a first step of simultaneously providing electrical power to the plurality of chips, thereby generating one or more light signals (120) corresponding to the one or more defects in the plurality of chips. The second step is simultaneously forming an image (150) of the plurality of chips so as to simultaneously detect the one or more light signals. The apparatus (10) for carrying out the method comprises electrical probes (30) for providing electrical power to the plurality of chips, a detector (60) to detect the one or more light signals emitted by the chips as a result of electrical power interacting with the one or more defects, and an imaging system (50) arranged so as to form an image of the plurality of chips, including the light signals, onto the detection surface (64).

Abstract: An integrated circuit chip (IC) is equipped with a device for preventing reverse engineering by monitoring light emissions emitted from transistors and such electrically active devices in a circuit located in the IC. The device can be an opaque structure that blocks emissions from being detected external to the IC. Alternatively, the device can reduce light emissions from the transistors to prevent detection of the light emissions external to the IC. The device, in another alternative, can emit extraneous light emissions to hide a pattern of light emissions emitted from the transistors. As a further alternative, the device can add random delay to a signal driving the transistors to randomize the pattern of light emissions emitted from the transistors to prevent detection of a predetermined pattern of light emissions external to the IC.

Abstract: An integrated circuit chip (IC) is equipped with a device for preventing reverse engineering by monitoring light emissions emitted from transistors and such electrically active devices in a circuit located in the IC. The device can be an opaque structure that blocks emissions from being detected external to the IC. Alternatively, the device can reduce light emissions from the transistors to prevent detection of the light emissions external to the IC. The device, in another alternative, can emit extraneous light emissions to hide a pattern of light emissions emitted from the transistors. As a further alternative, the device can add random delay to a signal driving the transistors to randomize the pattern of light emissions emitted from the transistors to prevent detection of a predetermined pattern of light emissions external to the IC.

Abstract: A method and apparatus for reverse engineering an integrated circuit chip (IC chip) (120) utilizes an electrical circuit tester (114) for injecting a triggering signal into the IC chip (120) to exercise a circuit under test. In synchronization thereto, a PICA detector (116) monitors optical emissions from the circuit under test. A spatial data extractor, electrically coupled to the PICA detector, collects space information (124) from patterns of light emissions emitted by the circuit under test, and a timing data extractor, electrically coupled to the electrical circuit tester and to the PICA detector (116), collects time information (126) from the patterns of light emissions emitted by the circuit under test. A database memory (105) includes known data about the circuit under test and also includes at least one reference pattern for comparing a captured light emission pattern thereto to identify at least one circuit element in the circuit under test.

Abstract: A system for time-correlated photon counting. The system uses one or more photon detectors to produce electrical pulses corresponding to photons read from a target. The system uses a discriminator with a first input coupled to a trigger output from a pulsed optical source and a second input for receiving the electrical pulses. A time-to-pulse height converter is used for producing a series of difference signals each with a respective maxima and whose magnitude is related to the time difference between the trigger output and the electrical pulses. In addition, the system employs a pulse shaping electronic circuit for receiving pulsed electrical output and producing a series of one or more characteristic signals. An A/D converter with a first input receives the difference signals and a second input receives part of the characteristic signals.

Abstract: This invention describes how commercial silicon-on-insulator material can be used to fabricate both wavelength filters and wavelength-selective photodetectors. The silicon-on-insulator substrates have a buried silicon dioxide layer and a thin top silicon layer and are manufactured for high speed electonics applications. However, in this invention, the thin silicon layer is used as the core of a waveguide and the buried silicon dioxide as a lower cladding region. Another cladding layer and a low index waveguide is fabricated on the commercial substrate to form an asymmetric waveguide coupler structure. The added low index waveguide and the original thin silicon layer form the two waveguides of the coupler. Since the the two waveguide materials have very different indices of refraction, they are only phase-matched at one wavelength. Thus for a given thickness of materials, only one wavelength couples between the two waveguides.

Abstract: An apparatus is described for obtaining single frequency laser operation in a coupled waveguide configuration without using a diffraction grating. More specifically, this invention is a laser structure for oscillating light in single longitudinal mode. This structure has a pair of coupled but dissimilar waveguides that are collinear with each other and separated by a mirror in contact with each of the guides. The length of the waveguides are adjusted so that frequency selective coupling between the waveguides can discriminate between wavelengths corresponding to different longitudinal modes.

Abstract: This invention covers an apparatus for generating multiple wavelengths of light, where the intensity of each wavelength is separately controlled, and where all the wavelengths exit the device from the same aperture. Structurally, this multiple wavelength source consists of a passive waveguide coupled to an active tapered resonator. The light generated in the resonator couples to the passive waveguide and exits from the ends of the device. By pumping different regions of the resonator, different wavelengths can be obtained.

Abstract: This invention covers apparatus for providing a compact, high resolution waveguide optical demultiplexer or spectrometer for application in optical communications. With this invention, incoming light composing many discrete wavelengths or optical channels is spectrally resolved by the waveguide demultiplexer such that the wavelength channels are separated spatially. The two major elements of this invention are a waveguide having a partial mirror along its length to reflect optical frequencies therein, and an optical resonator where one of its resonating mirrors is the partial mirror of the waveguide. Selected frequencies are then extracted from the waveguide and resonated in the resonator.

Abstract: Contactless probing of an integrated circuit is carried out by flooding the surface of the integrated circuit with pulsed ultraviolet laser light, causing photoelectron emission as a function of the potentials at micropoints on the integrated circuit, converting this two-dimensional electron pattern into a corresponding relatively long duration pattern of luminescence by a luminescent target, and reviewing the result by video/computer scanning. Separate embodiments allow testing either in vacuum or in air, with or without insulating passivation layers present on the chip. The result is a contactless oscilloscope which monitors instantaneous voltages (logic states and AC switching waveforms) for a full two-demsnsional array of micropoints simultaneously. A chip with test points and appropriate windows for laser activation and luminescent targeting can be specially designed for optimal testing.

Abstract: Contactless probing of an integrating circuit is carried out by flooding the surface of the integrated circuit with pulsed ultraviolet laser light, causing photoelectron emission as a function of the potentials at micropoints on the integrated circuit, converting this two-dimensional electron pattern into a corresponding relatively long duration pattern of luminescence by a luminescent target, and reviewing the result by video/computer scanning. Separate embodiments allow testing either in vacuum or in air, with or without insulating passivation layers present on the chip. The result is a contactless oscilloscope which monitors instantaneous voltage (logic states and AC switching waveforms) for a full two-dimensional array of micropoints simultaneously. A chip with test points and appropriate windows for laser activation and luminescent targeting can be specially designed for optimal testing.

Abstract: Picosecond response photoconductors and photoresponsive elements can be provided that retain high carrier mobility and yet have short lifetime by providing on a crystal mismatched substrate a textured layer of domain regions wherein the domain size is such that the lifetime is proportional to the square of the size divided by the diffusion coefficient of the semiconductor material. The crystalline orientation in the domains with respect to the substrate is maintained. An embodiment is an approximately 0.1 micron thick textured layer of <111> GaAs grown on a <0001> hexagonal monocrystalline Al.sub.2 O.sub.3 having domains approximately 1.0 micron with a carrier lifetime about 5 picoseconds and a carrier mobility of about 80 cm.sup.2 volt.sup.-1 sec.sup.-1.