InSb charge coupled infrared imaging device: The 20 element linear imager

The design and fabrication of the 8585 InSb charge coupled infrared imaging device (CCIRID) chip are reported. The InSb material characteristics are described along with mask and process modifications. Test results for the 2- and 20-element CCIRID's are discussed, including gate oxide characteristics, charge transfer efficiency, optical mode of operation, and development of the surface potential diagram

Stellar Occultation Studies of the Solar System

Earth-based observations of stellar occultations provide extremely high spatial resolution for bodies in the outer solar system, about 10,000 times better than that of traditional imaging observations. Stellar occultation data can be used to establish the structure of atmospheres and rings of solar system bodies at high spatial resolution. Airborne occultation observations are particularly effective, since the controlled mobility of the observing platform allows the observer to fly within the optimum part of the occultation shadow for most events that are visible from Earth. Airborne observations are carried out above any clouds and are nearly free of scintillation noise from the Earth's atmosphere. KAO occultation observations resulted in the first detection of gravity waves in the Martian atmosphere, discovery of the Uranian rings, the first detection of Pluto's atmosphere, the first Earth-based investigations of Triton's atmosphere, and the discovery of narrow jets from Chiron's nucleus. The first SOFIA occultation opportunity will be an investigation of Pluto's atmospheric structure in November, 2002, and will resolve a problem that has lingered since the KAO discovery observation fourteen years earlier. We plan to continue our successful airborne occultation program with the greatly enhanced capability provided by SOFIA. We propose here to replace our KAO occultation photometer with one having twice the throughput, half the noise, a somewhat wider wavelength range, four times the field of view, and ten times the frame rate to optimize its performance and to capitalize on the larger collecting area offered by SOFIA. It will also allow for simultaneous visible and IR occultation observations, greatly enriching the results that we can obtain from occultations. We call this new imaging occultation photometer HOPI (High-speed Occultation Photometer and Imager). HOPI will provide a signal-to-noise ratio two to four times that of our present photometer for a given event, will permit useful observations of the more numerous events involving fainter stars, and will allow higher time resolution observations to be made. HOPI's characteristics also make it an ideal instrument for initial and ongoing evaluations of the SOFIA telescope's performance

Overcoming the challenges in very deep submicron for area reduction, power reduction and faster design closure

The project is aimed at understanding the existing very deep sub-micron (VDSM) implementation of a digital design, analyzing it from the point of view of power, area and timing and to come up with solutions and strategies to optimize the implementation in terms of power, area and timing. The effort involved, to understand the constraints, reasons and the requirements resulting in the existing implementation of the design. Further, various experiments were carried out to improve the design in various aspects like power, area and timing. The tradeoffs required and the benefits of each of the experiments were contrasted and analyzed. The optimum solutions and strategies which balance the requirements were tried out and published at the end of the report

Stellar Occultation Studies of the Solar System

Earth-based observations of stellar occultations provide extremely high spatial resolution for bodies in the outer solar system, about 10,000 times better than that of traditional imaging observations. Stellar occultation data can be used to establish the structure of atmospheres and rings of solar system bodies at high spatial resolution. Airborne occultation observations are particularly effective, since the controlled mobility of the observing platform allows the observer to fly within the optimum part of the occultation shadow for most events that are visible from Earth. Airborne observations are carried out above any clouds and are nearly free of scintillation noise from the Earth's atmosphere. KAO occultation observations resulted in the first detection of gravity waves in the Martian atmosphere, discovery of the Uranian rings, the first detection of Pluto's atmosphere, the first Earth-based investigations of Triton's atmosphere, and the discovery of narrow jets from Chiron's nucleus. The first SOFIA occultation opportunity will be an investigation of Pluto's atmospheric structure in November, 2002, and will resolve a problem that has lingered since the KAO discovery observation fourteen years earlier. We plan to continue our successful airborne occultation program with the greatly enhanced capability provided by SOFIA. We propose here to replace our KAO occultation photometer with one having twice the throughput, half the noise, a somewhat wider wavelength range, four times the field of view, and ten times the frame rate to optimize its performance and to capitalize on the larger collecting area offered by SOFIA. It will also allow for simultaneous visible and IR occultation observations, greatly enriching the results that we can obtain from occultations. We call this new imaging occultation photometer HOPI (High-speed Occultation Photometer and Imager). HOPI will provide a signal-to-noise ratio two to four times that of our present photometer for a given event, will permit useful observations of the more numerous events involving fainter stars, and will allow higher time resolution observations to be made. HOPI's characteristics also make it an ideal instrument for initial and ongoing evaluations of the SOFIA telescope's performance

Engineering evaluations and studies. Volume 2: Exhibit B, part 1

Ku-band communication system analysis, S-band system investigations, payload communication investigations, shuttle/TDRSS and GSTDN compatibility analysis are discussed

Nonpolar GaN-Based VCSELs with Lattice-Matched Nanoporous Distributed Bragg Reflector Mirrors

Wide-bandgap optoelectronic devices have undergone significant advancements with the advent of commercial light-emitting diodes and edge-emitting lasers in the violet-blue spectral region. They are now ubiquitous in several lighting, communication, data storage, display, and sensing applications. Among the III-nitride emitters, vertical-cavity surface-emitting lasers (VCSELs) have attracted significant attention in recent years due to their inherent advantages over edge-emitting lasers. The small active volume enables single-mode operation with low threshold currents and high modulation bandwidths. Their surface-normal device geometry is conducive to the cost-effective formation of high-density 2D arrays while simplifying on-chip wafer testing. Furthermore, the low beam divergence and circular beam profiles in VCSELs allow efficient fiber coupling. Nevertheless, GaN-based VCSELs are still in the early stages of development. Several challenges need to be addressed before high-performance devices can be commercially realized. One such challenge is the lack of high-quality distributed Bragg reflector (DBR) mirrors. Conventionally, epitaxial and dielectric DBRs are used which often involve complex growth and fabrication techniques. This dissertation provides an alternative approach where subwavelength air-voids (nanopores) are introduced in alternating layers of doped/undoped GaN to form the DBR structure. Selective electrochemical etching creates nanopores in the doped layers, reducing the effective refractive index relative to the surrounding undoped GaN. Using only 16-pairs, DBR reflectance \u3e99.9% could be achieved. Several research groups have shown optically pumped VCSELs using nanoporous DBRs on c-plane. However, there are no reports of electrically injected nanoporous VCSELs. Using m-plane GaN substrates, we have demonstrated the first ever electrically injected GaN-based VCSEL using a lattice-matched nanoporous DBR. The nonpolar m-plane orientation is beneficial for leveraging the higher per-pass gain and polarization-pinning properties absent in c-plane. Lasing under pulsed operation at room temperature was observed at 409 nm with a linewidth of ~0.6 nm and a maximum output power of ~1.5 mW. This is the highest output power from m-plane VCSELs to date with relatively stable operation at elevated temperatures. All tested devices were linearly polarization-pinned in the a-direction with high polarization ratios \u3e0.9. Overall, the nanoporous DBRs help in mitigating some of the issues that limit the performance of III-nitride VCSELs

A Physical Unclonable Function derived from the power distribution system of an integrated circuit

Hardware support for security mechanisms such as authentication, cryptographic protocols, digital rights management and hardware metering depend heavily on the security of embedded secret keys. The current practice of embedding these keys as digital data in the Integrated Circuit (IC) weakens security because the keys can be learned through attacks. Physical Unclonable Functions (PUFs) are a recently- proposed alternative to storing digital keys on the IC. A PUF leverages the inherent manufacturing variations of an IC to define a random function. However, poor performance under PUF quality criteria such as the level of randomness and reproducibility in the responses have detracted from their adoption and widespread use. In this dissertation, I propose several ways to define a novel PUF using the Power Distribution System (PDS) of an IC. First, I describe the hardware primitive and test setup that is required to obtain the PUF responses. Then, I evaluate the analog PUF responses from silicon against standard PUF quality metrics in order to qualify the strengths and weaknesses of the proposed PUF. I show that the analog PUFs ex- hibit very high levels of randomness and reproducibility, but are sensitive to changes in temperature. Next, I propose extensions to our PUF that enable an exponential number of Challenge/Response Pairs (CRPs) with respect to the number of hardware resources, as well as yielding a marginal increase in the level of randomness. I also use these same analog measurements from silicon to simulate an integrated implementation of the PUF that takes a digital challenge and returns a digital response. I show that the integrated architecture also exhibits high levels of randomness and reproducibility, and is also resistant to changes in temperature. Future work includes designing and building a new IC that implements a more powerful hardware primitive that will improve both the number and accuracy of the measurements, as well as additional hardware that will allow the challenge and response generation to be performed on-chip

Conference on Charge-Coupled Device Technology and Applications

Papers were presented from the conference on charge coupled device technology and applications. The following topics were investigated: data processing; infrared; devices and testing; electron-in, x-ray, radiation; and applications. The emphasis was on the advances of mutual relevance and potential significance both to industry and NASA's current and future requirements in all fields of imaging, signal processing and memory

Network-on-Chip

Addresses the Challenges Associated with System-on-Chip Integration Network-on-Chip: The Next Generation of System-on-Chip Integration examines the current issues restricting chip-on-chip communication efficiency, and explores Network-on-chip (NoC), a promising alternative that equips designers with the capability to produce a scalable, reusable, and high-performance communication backbone by allowing for the integration of a large number of cores on a single system-on-chip (SoC). This book provides a basic overview of topics associated with NoC-based design: communication infrastructure design, communication methodology, evaluation framework, and mapping of applications onto NoC. It details the design and evaluation of different proposed NoC structures, low-power techniques, signal integrity and reliability issues, application mapping, testing, and future trends. Utilizing examples of chips that have been implemented in industry and academia, this text presents the full architectural design of components verified through implementation in industrial CAD tools. It describes NoC research and developments, incorporates theoretical proofs strengthening the analysis procedures, and includes algorithms used in NoC design and synthesis. In addition, it considers other upcoming NoC issues, such as low-power NoC design, signal integrity issues, NoC testing, reconfiguration, synthesis, and 3-D NoC design. This text comprises 12 chapters and covers: The evolution of NoC from SoC—its research and developmental challenges NoC protocols, elaborating flow control, available network topologies, routing mechanisms, fault tolerance, quality-of-service support, and the design of network interfaces The router design strategies followed in NoCs The evaluation mechanism of NoC architectures The application mapping strategies followed in NoCs Low-power design techniques specifically followed in NoCs The signal integrity and reliability issues of NoC The details of NoC testing strategies reported so far The problem of synthesizing application-specific NoCs Reconfigurable NoC design issues Direction of future research and development in the field of NoC Network-on-Chip: The Next Generation of System-on-Chip Integration covers the basic topics, technology, and future trends relevant to NoC-based design, and can be used by engineers, students, and researchers and other industry professionals interested in computer architecture, embedded systems, and parallel/distributed systems

Resonant Detection of Nano to Microscopic Objects Using Whispering Gallery Modes

A micron sized glass sphere is able to confine light to its interior volume. The trapped light describes an orbital trajectory circumnavigating just below the microsphere surface. Whenever the light ray tries to escape it is sent back on its circular path by total internal reflection. The light orbit closes in on itself several thousand times and thus creates an optical resonance. The unprecedented narrow linewidth of such a microsphere resonance (Q factors of up to 3 x 10 ) allows precise measurement of its frequency. Dielectric microspheres of very high Q are thus the ideal choice for a resonant molecular sensor. Although the resonance is stealth, an evanescent field extends from the microsphere surface the distance of a wavelength into the surrounding medium. This thesis demonstrates how label-free molecules binding to the microsphere surface perturb the optical resonance by interaction with this evanescent field. The effect is demonstrated by surface adsorption of a protein (serum albumin). The general use as a biosensor is shown by specific detection of streptavidin binding to biotin. A first order perturbation theory describing the linear response of the sensor is presented. Molecular perturbation leads to a wavelength shift that can be measured with such high precision that single molecule detection seems theoretically possible. The experimental approach is extended to the multiplexed measurement of D N A hybridization using two microsphere resonators. This differential measurement allows the detection of a single nucleotide mismatch with a high signal to noise ratio. The effect of larger Mie particles such as bacteria and polystytrene nanospheres perturbing the cavity resonance is examined experimentally and theoretically. For such larger objects it is necessary to include the decay length of the evanescent field in the theoretical analysis. The Q spoiling which occurs for such large Mie particles is described by an analytic formula. Furthermore, a pairing effect is observed for polystyrene nanospheres with diameters of ~ a quarter wavelength polarized in the evanescent field of the microsphere resonance. A novel mechanism might be involved since the coupling cannot be explained by simple dipole-dipole interactions