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Summary of the EO-1 ALI performance during the first 2.5 years on-orbit

August 3, 2003
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Conference Paper
Author:
Jeffrey A. Mendenhall
…
Published in:
SPIE Vol. 5151, Earth Observing Systems VIII, 3-8 August 2003, pp. 574-585.
Topic:
satellites
R&D area:
R&D group:

Summary

The Advanced Land Imager (ALI) is a VNIR/SWIR, pushbroom instrument that is flying aboard the Earth Observing-1 (EO-1) spacecraft. Launched on November 21, 2000, the objective of the ALI is to flight validate emerging technologies that can be infused into future land imaging sensors. During the first two and one-half years on-orbit, the performance of the ALI has been evaluated using on-board calibrators and vicarious observations. The results of this evaluation are presented here. The spatial performance of the instrument, derived using stellar, lunar, and bridge observations, is summarized. The radiometric stability of the focal plane and telescope, established using solar, lunar, ground truth, and on-board sources, is also provided.
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Summary

The Advanced Land Imager (ALI) is a VNIR/SWIR, pushbroom instrument that is flying aboard the Earth Observing-1 (EO-1) spacecraft. Launched on November 21, 2000, the objective of the ALI is to flight validate emerging technologies that can be infused into future land imaging sensors. During the first two and one-half...

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Summary of the EO-1 ALI performance during the first 2.5 years on-orbit

Overview of the Earth Observing One (EO-1) mission

June 1, 2003
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Journal Article
Author:
S. G. Ungar
…
Published in:
IEEE Trans. Geosci. Remote Sens., Vol. 41, No. 6, Pt. 1, June 2003, pp. 1149-1159.
Topic:
satellites
R&D area:
R&D group:

Summary

The Earth Observing One (EO-1) satellite, a part of National Aeronautics and Space Administration's New Millennium Program, was developed to demonstrate new technologies and strategies for improved earth observations. It was launched from Vandenburg Air Force Base on November 21, 2000. The EO-1 satellite contains three observing instruments supported by a variety of newly developed space technologies. The Advanced Land Imager (ALI) is a prototype for a new generation of Landsat-7 Thematic Mapper. The Hyperion Imaging Spectrometer is the first high spatial resolution imaging spectrometer to orbit the earth. The Linear Etalon Imaging Spectral Array (LEISA) Atmospheric Corrector (LAC) is a high spectral resolution wedge imaging spectrometer designed to measure atmospheric water vapor content. Instrument performances are validated and carefully monitored through a combination of radiometric calibration approaches: solar, lunar, stellar, earth (vicarious), and atmospheric observations complemented by onboard calibration lamps and extensive prelaunch calibration. Techniques for spectral calibration of space-based sensors have been tested and validated with Hyperion. ALI and Hyperion instrument performance continue to meet or exceed predictions well beyond the planned one-year program. This paper reviews the EO-1 satellite system and provides details of the instruments and their performance as measured during the first year of operation. Calibration techniques and tradeoffs between alternative approaches are discussed. An overview of the science applications for instrument performance assessment is presented.
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Summary

The Earth Observing One (EO-1) satellite, a part of National Aeronautics and Space Administration's New Millennium Program, was developed to demonstrate new technologies and strategies for improved earth observations. It was launched from Vandenburg Air Force Base on November 21, 2000. The EO-1 satellite contains three observing instruments supported by...

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Overview of the Earth Observing One (EO-1) mission

Marathon evaluation of optical materials for 157-nm lithography

January 1, 2003
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Journal Article
Author:
Vladimir Liberman
…
Published in:
J. Microlithogr., Microfab., Microsyst., Vol. 2, No. 1, January 2003, pp. 19-26.
Topic:
lithography
R&D area:
R&D group:

Summary

We present the methodology and recent results on the longterm evaluation of optical materials for 157-nm lithographic applications. We review the unique metrology capabilities that have been developed for accurately assessing optical properties of samples both online and offline, utilizing VUV spectrophotometry with in situlamp-based cleaning. We describe ultraclean marathon testing chambers that have been designed to decouple effects of intrinsic material degradation from extrinsic ambient effects. We review our experience with lithography-grade 157-nm lasers and detector durability. We review the current status of bulk materials for lenses, such as CaF(2) and BaF(2), and durability results of antireflectance coatings. Finally, we discuss the current state of laser durability of organic pellicles.
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Summary

We present the methodology and recent results on the longterm evaluation of optical materials for 157-nm lithographic applications. We review the unique metrology capabilities that have been developed for accurately assessing optical properties of samples both online and offline, utilizing VUV spectrophotometry with in situlamp-based cleaning. We describe ultraclean marathon...

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Marathon evaluation of optical materials for 157-nm lithography

Investigation of the physical and practical limits of dense-only phase shift lithography for circuit feature definition

October 1, 2002
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Journal Article
Author:
Brian M. Tyrrell
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Published in:
J. Microlith., Microfab., Microsyst., Vol. 1, No. 3, October 2002, pp. 243-252.
Topic:
integrated circuit
R&D area:
R&D group:

Summary

The rise of low- k1 optical lithography in integrated circuit manufacturing has introduced new questions concerning the physical and practical limits of particular subwavelength resolution-enhanced imaging approaches. For a given application, trade-offs between mask complexity, design cycle time, process latitude and process throughput must be well understood. It has recently been shown that a dense-only phase shifting mask (PSM) approach can be applied to technology nodes approaching the physical limits of strong PSM with no proximity effects. Such an approach offers the benefits of reduced mask complexity and design cycle time, at the expense of decreased process throughput and limited design flexibility. In particular, dense-only methods offer k1,0.3, thus enabling 90 nm node lithography with high-numerical aperture 248 nm exposure systems. We present the results of experiments, simulations, and analysis designed to explore the trade-offs inherent in dense-only phase shift lithography. Gate and contact patterns corresponding to various fully scaled circuits are presented, and the relationship between process complexity and design latitude is discussed. Particular attention is given to approaches for obtaining gate features in both the horizontal and vertical orientation. Since semiconductor investment is dependent on cost amortization, the applicability of these methods is also considered in terms of production volume.
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Summary

The rise of low- k1 optical lithography in integrated circuit manufacturing has introduced new questions concerning the physical and practical limits of particular subwavelength resolution-enhanced imaging approaches. For a given application, trade-offs between mask complexity, design cycle time, process latitude and process throughput must be well understood. It has recently...

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Investigation of the physical and practical limits of dense-only phase shift lithography for circuit feature definition

High-speed, electronically shuttered solid-state imager technology

July 8, 2002
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Conference Paper
Author:
Robert K. Reich
…
Published in:
Rev. Sci. Instrum. Vol. 74, No. 3, Pt. II, March 2003, pp. 2027-2031 (Proceedings of the 14th Topical Conference on High-Temperature Plasma Diagnostics, 8-11 July 2002)
Topic:
electronics
R&D area:
R&D group:

Summary

Electronically shuttered solid-state imagers are being developed for high-speed imaging applications. A 5 cmx5 cm, 512x512-element, multiframe charge-coupled device (CCD) imager has been fabricated for the Los Alamos National Laboratory DARHT facility that collects four sequential image frames at megahertz rates. To operate at fast frame rates with high sensitivity, the imager uses an electronic shutter technology designed for back-illuminated CCDs. The design concept and test results are described for the burst-frame-rate imager. Also discussed is an evolving solid-state imager technology that has interesting characteristics for creating large-format x-ray detectors with short integration times (100 ps to 1 ns). Proposed device architectures use CMOS technology for high speed sampling (tens of picoseconds transistor switching times). Techniques for parallel clock distribution, that triggers the sampling of x-ray photoelectrons, will be described that exploit features of CMOS technology.
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Summary

Electronically shuttered solid-state imagers are being developed for high-speed imaging applications. A 5 cmx5 cm, 512x512-element, multiframe charge-coupled device (CCD) imager has been fabricated for the Los Alamos National Laboratory DARHT facility that collects four sequential image frames at megahertz rates. To operate at fast frame rates with high sensitivity...

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High-speed, electronically shuttered solid-state imager technology

Flight test results of the Earth Observing-1 Advanced Land Imager

July 7, 2002
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Conference Paper
Author:
Jeffrey A. Mendenhall
…
Published in:
SPIE, Vol. 4814, Earth Observing Systems VII, 7-10 July 2002, pp. 296-305.
Topic:
satellites
R&D area:
R&D group:

Summary

The Advanced Land Imager (ALI) is the primary instrument on the Earth Observing-1 spacecraft (EO-1) and was developed under NASA's New Millennium Program (NMP). The NMP mission objective is to flight-validate advanced technologies that will enable dramatic improvements in performance, cost, mass, and schedule for future, Landsat-like, Earth Science Enterprise instruments. ALI contains a number of innovative features designed to achieve this objective. These include the basic instrument architecture, which employs a push-broom data collection mode, a wide field-of-view optical design, compact multi-spectral detector arrays, non-cryogenic HgCdTe for the short wave infrared bands, silicon carbide optics, and a multi-level solar calibration technique. The sensor includes detector arrays that operate in ten bands, one panchromatic, six VNIR and three SWIR, spanning the range fiom 0.433 to 2.35 um. Launched on November 21, 2000, ALI instrument performance was monitored during its first year on orbit using data collected during solar, lunar, stellar, and earth observations. This paper will provide an overview of EO-1 mission activities during this period. Additionally, the on-orbit spatial and radiometric performance of the instrument will be compared to pre-flight measurements and the temporal stability of ALI will be presented.
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Summary

The Advanced Land Imager (ALI) is the primary instrument on the Earth Observing-1 spacecraft (EO-1) and was developed under NASA's New Millennium Program (NMP). The NMP mission objective is to flight-validate advanced technologies that will enable dramatic improvements in performance, cost, mass, and schedule for future, Landsat-like, Earth Science Enterprise...

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Flight test results of the Earth Observing-1 Advanced Land Imager

Proton irradiations of large area Hg(1-x)Cd(x)Te photovoltaic detectors for the cross-track infrared sounder

July 7, 2002
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Conference Paper
Author:
Michael W. Kelly
…
Published in:
SPIE Vol. 4820, Pt. 1, Infrared Technology and Applications XXVIII, 7-11 July 2002, pp. 479-490.
Topic:
remote sensing
R&D area:
R&D group:

Summary

The effect of radiation on Hg(1-x)Cd(x)Te photodiodes is an important parameter to understand when determining the long-term performance limitations for the Cross-track Infrared Sounder (CrIS), a Fourier Transform interferometric sensor that will fly as part of the National Polar-orbiting Operational Enviornmental Satellite System (NPOESS). The CrIS sensor uses relatively large area photovoltaic detectors, 1mm in diameter. Each p-on-n Hg(1-x)Cd(x)Te photodiode consists of MBE grown, n-type material on lattice matched CdZnTe, with arsenic implantation used to form the junction. A 1mm diameter detector is achieved by using a lateral collection. Solar, and trapped protons are a significant source of radiation in the NPOESS 833 km orbits. We irradiated 22 LWIR detectors with protons at the Harvard Cyclotron Laboratory (HCL) and monitored the I-V performance and dynamic impedance of each detector. Three groups of detectors were irradiated with either 44, 99, 153-MeV protons, each between 1x10(10) - 4x10(12) p+/cm(2) (total range ~ 0.7 - 690 krad(Si)). Several I-V data sets were collected within that fluence range at all three energies. All the detectors were warmed to room temperature for approximately 96 hours following the largest proton dose, recooled, and then re-characterized in terms of I-V performance and dynamic impedance. The total noise increase predicted for CrIS after 7-years in orbit is less than 1%.
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Summary

The effect of radiation on Hg(1-x)Cd(x)Te photodiodes is an important parameter to understand when determining the long-term performance limitations for the Cross-track Infrared Sounder (CrIS), a Fourier Transform interferometric sensor that will fly as part of the National Polar-orbiting Operational Enviornmental Satellite System (NPOESS). The CrIS sensor uses relatively large...

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Proton irradiations of large area Hg(1-x)Cd(x)Te photovoltaic detectors for the cross-track infrared sounder

Broadband (200-1000 nm) back-illuminated ccd imagers

June 16, 2002
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Conference Paper
Author:
Barry E. Burke
…
Published in:
Scientific Detectors Workshop 2002, 16-22 June 2002.p. 41-50.
Topic:
optics
R&D area:
R&D group:

Summary

Improved and stable blue/UV quantum efficiency has been demonstrated on 2Kx4K imagers using molecular-beam epitaxy to create a thin doped layer on the back surface. Quantum efficiency data on thick (40-50 pm) imagers with single and dual-layer anti-reflection coatings is presented that demonstrates high and broadband response. Measurements of the optical point-spread response show the devices to be fully depleted with good response across a broad spectrum, but interesting features appear in the near-IR as a result of deeply penetrating light being scattered off the surface structure of the CCD.
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Summary

Improved and stable blue/UV quantum efficiency has been demonstrated on 2Kx4K imagers using molecular-beam epitaxy to create a thin doped layer on the back surface. Quantum efficiency data on thick (40-50 pm) imagers with single and dual-layer anti-reflection coatings is presented that demonstrates high and broadband response. Measurements of the...

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Broadband (200-1000 nm) back-illuminated ccd imagers

Geiger-mode avalanche photodiodes for three-dimensional imaging

January 1, 2002
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Journal Article
Author:
Brian F. Aull
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Published in:
Lincoln Laboratory Journal, Vol. 13, No. 2, 2002, pp. 335-350.
Topic:
ladar
R&D area:
R&D group:

Summary

We discuss the properties of Geiger-mode avalanche photodiodes (APDs) and their use in developing an imaging laser radar (ladar). This type of photodetector gives a fast electrical pulse in response to the detection of even a single photon, allowing for sub-nsec-precision photon-flight-time measurement. We present ongoing work at Lincoln Laboratory on three-dimensional (3D) imaging with arrays of these diodes, and the integration of the arrays with fast complementary metal-oxide semiconductor (CMOS) digital timing circuits.
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Summary

We discuss the properties of Geiger-mode avalanche photodiodes (APDs) and their use in developing an imaging laser radar (ladar). This type of photodetector gives a fast electrical pulse in response to the detection of even a single photon, allowing for sub-nsec-precision photon-flight-time measurement. We present ongoing work at Lincoln Laboratory...

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Geiger-mode avalanche photodiodes for three-dimensional imaging

Silicon-on-insulator-based single-chip image sensors: low-voltage scientific imaging

January 1, 2002
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Conference Paper
Author:
Vyshnavi Suntharalingam
…
Published in:
Experimental Astronomy, Vol. 14, No. 2, 2002, pp. 91-98.
Topic:
sensors
R&D area:
R&D group:

Summary

A low-voltage (
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Summary

A low-voltage (

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Silicon-on-insulator-based single-chip image sensors: low-voltage scientific imaging
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