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Enhancing the far-ultraviolet sensitivity of silicon complementary metal oxide semiconductor imaging arrays

October 1, 2015
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Journal Article
Author:
Kurt D. Retherford
…
Published in:
J. Astron. Telesc. Instrum. Syst., Vol. 1, No. 4, Oct. - Dec. 2015, 046001.
Topic:
semiconductor (CMOS)
R&D area:
R&D group:

Summary

We report our progress toward optimizing backside-illuminated silicon P-type intrinsic N-type complementary metal oxide semiconductor devices developed by Teledyne Imaging Sensors (TIS) for far-ultraviolet (UV) planetary science applications. This project was motivated by initial measurements at Southwest Research Institute of the far-UV responsivity of backside-illuminated silicon PIN photodiode test structures, which revealed a promising QE in the 100 to 200 nm range. Our effort to advance the capabilities of thinned silicon wafers capitalizes on recent innovations in molecular beam epitaxy (MBE) doping processes. Key achievements to date include the following: (1) representative silicon test wafers were fabricated by TIS, and set up for MBE processing at MIT Lincoln Laboratory; (2) preliminary far-UV detector QE simulation runs were completed to aid MBE layer design; (3) detector fabrication was completed through the pre-MBE step; and (4) initial testing of the MBE doping process was performed on monitoring wafers, with detailed quality assessments.
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Summary

We report our progress toward optimizing backside-illuminated silicon P-type intrinsic N-type complementary metal oxide semiconductor devices developed by Teledyne Imaging Sensors (TIS) for far-ultraviolet (UV) planetary science applications. This project was motivated by initial measurements at Southwest Research Institute of the far-UV responsivity of backside-illuminated silicon PIN photodiode test structures...

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Enhancing the far-ultraviolet sensitivity of silicon complementary metal oxide semiconductor imaging arrays

Development and application of spherically curved charge-coupled device imagers

April 1, 2015
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Journal Article
Author:
James A. Gregory
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Published in:
Appl. Opt., Vol. 54, No. 10, 1 April 2015, pp. 3072-82.
Topic:
optics
R&D area:
R&D group:

Summary

Operation of a CCD imager on a curved focal surface offers advantages to flat focal planes, especially for lightweight, relatively simple optical systems. The first advantage is that the modulation transfer function can approach diffraction-limited performance for a spherical focal surface employed in large field-of-view or large-format imagers. The second advantage is that a curved focal surface maintains more uniform illumination as a function of radius from the field center. Examples of applications of curved imagers, described here, include a small compact imager and the large curved array used in the Space Surveillance Telescope. The operational characteristics and mechanical limits of an imager deformed to a 15 mm radius are also described.
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Summary

Operation of a CCD imager on a curved focal surface offers advantages to flat focal planes, especially for lightweight, relatively simple optical systems. The first advantage is that the modulation transfer function can approach diffraction-limited performance for a spherical focal surface employed in large field-of-view or large-format imagers. The second...

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Development and application of spherically curved charge-coupled device imagers

Adaptive optics program at TMT

September 5, 2014
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Conference Paper
Author:
Colby Boyer
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Published in:
SPIE, Vol. 9148, Adaptive Optics Systems IV, 5 September 2014, 914801.
Topic:
optics
R&D area:
R&D group:

Summary

The TMT first light Adaptive Optics (AO) facility consists of the Narrow Field Infra-Red AO System (NFIRAOS) and the associated Laser Guide Star Facility (LGSF). NFIRAOS is a 60 x 60 laser guide star (LGS) multi-conjugate AO (MCAO) system, which provides uniform, diffraction-limited performance in the J, H, and K bands over 17-30 arc sec diameter fields with 50 per cent sky coverage at the galactive pole, as required to support the TMT science cases. NFIRAOS includes two deformable mirrors, six laser guide star wavefront sensors, and three low-order, infrared, natural guide star wavefront sensors within each client instument. The first light LGSF system includes six sodium lasers required to generate the NFIRAOS laser guide stars. In this paper, we will provide an update on the progress in designing, modeling, and validating the TMT first light AO systems and their components over the last two years. This will include pre-final design and prototyping for the deformable mirrors, fabrication and tests for the visible detectors, benchmarking and comparison of different algorithms and processing architecture for the Real Time Controller (RTC) and development tests of prototype candidate lasers. Comprehensive and detailed AO modeling is continuing to support the design and development of the first light AO facility. Main modeling topics studied during the last two years include further studies in the area of wavefront error budget, sky coverage, high precision astrometry for the galactic center and other observations, high contrast imaging with NFIRAOS and its first light instruments, Point Spread Function (PSF) reconstruction for LGS MCAO, LGS photon return and sophisticated low order mode temporal filtering.
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Summary

The TMT first light Adaptive Optics (AO) facility consists of the Narrow Field Infra-Red AO System (NFIRAOS) and the associated Laser Guide Star Facility (LGSF). NFIRAOS is a 60 x 60 laser guide star (LGS) multi-conjugate AO (MCAO) system, which provides uniform, diffraction-limited performance in the J, H, and K...

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Adaptive optics program at TMT

A photon-counting detector for exoplanet missions

September 5, 2011
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Conference Paper
Author:
Donald F. Figer
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Published in:
SPIE Vol. 8151, Techniques and Instrumentation for Detection of Exoplanets V, 5 September 2011, 81510K.
Topic:
photonics
R&D area:
R&D group:

Summary

This paper summarizes progress of a project to develop and advance the maturity of photon-counting detectors for NASA exoplanet missions. The project, funded by NASA ROSES TDEM program, uses a 256x256 pixel silicon Geiger-mode avalanche photodiode (GM-APD) array, bump-bonded to a silicon readout circuit. Each pixel independently registers the arrival of a photon and can be reset and ready for another photon within 100 ns. The pixel has built-in circuitry for counting photo-generated events. The readout circuit is multiplexed to read out the photon arrival events. The signal chain is inherently digital, allowing for noiseless transmission over long distances. The detector always operates in photon counting mode and is thus not susceptible to excess noise factor that afflicts other technologies. The architecture should be able to operate with shot-noise-limited performance up to extremely high flux levels, >106 photons/second/pixel, and deliver maximum signal-to-noise ratios on the order of thousands for higher fluxes. Its performance is expected to be maintained at a high level throughout mission lifetime in the presence of the expected radiation dose.
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Summary

This paper summarizes progress of a project to develop and advance the maturity of photon-counting detectors for NASA exoplanet missions. The project, funded by NASA ROSES TDEM program, uses a 256x256 pixel silicon Geiger-mode avalanche photodiode (GM-APD) array, bump-bonded to a silicon readout circuit. Each pixel independently registers the arrival...

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A photon-counting detector for exoplanet missions

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

June 16, 2002
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Conference Paper
Author:
Barry E. Burke
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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

Soft-x-ray CCD imagers for AXAF

October 1, 1997
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Journal Article
Author:
Barry E. Burke
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Published in:
IEEE Trans. Electron Devices, Vol. 44, No. 10, October 1997, pp. 1633-1642.
Topic:
sensors
R&D area:
R&D group:

Summary

We describe the key features and performance data of a 1024 x 1026-pixel frame-transfer imager for use as a soft-x-ray detector on the NASA X-ray observatory Advanced X-ray Astrophysics Facility (AXAF). The four-port device features a floating-diffusion output circuit with a responsivity of 20/spl mu/V/e/sup -/ and noise of about 2 e/sup -/ at a 100-kHz data rate. Techniques for achieving the low sense-node capacitance of 5 fF are described. The CCD is fabricated on high-resistivity p-type silicon for deep depletion and includes narrow potential troughs for transfer inefficiencies of around 10/sup -7/ (ten to the negative 7). To achieve good sensitivity at energies below 1 keV, we have developed a back-illumination process that features low recombination losses at the back surface and has produced efficiencies of about 0.7 at 277 eV (carbon K/spl alpha/).
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Summary

We describe the key features and performance data of a 1024 x 1026-pixel frame-transfer imager for use as a soft-x-ray detector on the NASA X-ray observatory Advanced X-ray Astrophysics Facility (AXAF). The four-port device features a floating-diffusion output circuit with a responsivity of 20/spl mu/V/e/sup -/ and noise of about...

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Soft-x-ray CCD imagers for AXAF
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