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A study of crosstalk in a 256 x 256 photon counting imager based on silicon Geiger-mode avalanche photodiodes

April 1, 2015
  |
Journal Article
Author:
Brian F. Aull
…
Published in:
IEEE Sens. J., Vol. 15, No. 4, April 2015, pp. 2123-32.
Topic:
photonics
R&D area:
R&D group:

Summary

We demonstrate a 256 x 256 passive photon counting imager based on hybridization of back-illuminated silicon Geiger-mode avalanche photodiodes to an all-digital CMOS counting chip. Photon detection efficiencies in the 10%-20% are observed at visible wavelengths. The detection efficiency is currently limited by optical crosstalk that leads to elevation of dark count rates as the bias voltage on the photodiodes is increased. Both the time dependence of dark count activity during a gate time and the spatial structure of dark images were successfully explained using crosstalk-based models.
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Summary

We demonstrate a 256 x 256 passive photon counting imager based on hybridization of back-illuminated silicon Geiger-mode avalanche photodiodes to an all-digital CMOS counting chip. Photon detection efficiencies in the 10%-20% are observed at visible wavelengths. The detection efficiency is currently limited by optical crosstalk that leads to elevation of...

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A study of crosstalk in a 256 x 256 photon counting imager based on silicon Geiger-mode avalanche photodiodes

Detection statistics in Geiger-mode avalanche photodiode quad-cell arrays with crosstalk and dead time

April 1, 2015
  |
Journal Article
Author:
Brian F. Aull
…
Published in:
IEEE Sens. J., Vol. 15, No. 4, April 2015, pp. 2133-43.
Topic:
optics
R&D area:
R&D group:

Summary

The detection statistics of Geiger-mode photodetector subarrays with a combination of reset-time blocking loss and optical crosstalk are investigated. Closed-form expressions are obtained for the means and covariances of the numbers of counts in 2 x 2 subarrays (quad cells) used in Shack-Hartmann wavefront sensors. The predicted wavefront sensing precision is compared with that obtained with a charge-coupled device-based wavefront sensor with readout noise. The results of the theory are also used to predict photon transfer curves for the Geiger-mode device and these are compared with experiment.
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Summary

The detection statistics of Geiger-mode photodetector subarrays with a combination of reset-time blocking loss and optical crosstalk are investigated. Closed-form expressions are obtained for the means and covariances of the numbers of counts in 2 x 2 subarrays (quad cells) used in Shack-Hartmann wavefront sensors. The predicted wavefront sensing precision...

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Detection statistics in Geiger-mode avalanche photodiode quad-cell arrays with crosstalk and dead time

Gigahertz (GHz) hard X-ray imaging using fast scintillators

September 26, 2013
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Conference Paper
Author:
Zhehui Wang
…
Published in:
SPIE Vol. 8852, Hard X-Ray, Gamma-Ray, and Neutron Detector Physics XV, 26 September 2013, 88521A.
Topic:
optics
R&D area:
R&D group:

Summary

Gigahertz (GHz) imaging technology will be needed at high-luminosity X-ray and charged particle sources. It is plausible to combine fast scintillators with the latest picosecond detectors and GHz electronics for multi-frame hard X-ray imaging and achieve an inter-frame time of elss than 10 ns. The time responses and light yield of LYSO, LaBr3, BaF2 and ZnO are measured using an MCP-PMT detector. Zinc Oxide (ZnO) is an attractive material for fast hard X-ray imaging based on GEANT4 simulations and previous studies, but the measured light yield from the samples is much lower than expected.
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Summary

Gigahertz (GHz) imaging technology will be needed at high-luminosity X-ray and charged particle sources. It is plausible to combine fast scintillators with the latest picosecond detectors and GHz electronics for multi-frame hard X-ray imaging and achieve an inter-frame time of elss than 10 ns. The time responses and light yield...

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Gigahertz (GHz) hard X-ray imaging using fast scintillators

A 64 x 64-pixel CMOS test chip for the development of large-format ultra-high-speed snapshot imagers

September 1, 2008
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Journal Article
Author:
Robert Berger
…
Published in:
IEEE J. Solid-State Circuits, Vol. 43, No. 9, September 2008, pp. 1940-1950.
Topic:
sensors
R&D area:
R&D group:

Summary

A 64 x 64-pixel test circuit was designed and fabricated in 0.18- m CMOS technology for investigating high-speed imaging with large-format imagers. Several features are integrated into the circuit architecture to achieve fast exposure times with low-skew and jitter for simultaneous pixel snapshots. These features include an H-tree clock distribution with local and global repeaters, single-edge trigger propagation, local exposure control, and current-steering sampling circuits. To evaluate the circuit performance, test structures are periodically located throughout the 64 x 64-pixel device. Measured devices have exposure times that can be varied between 75 ps to 305 ps with skew times for all pixels less than +-3 ps and jitter that is less than +-1.2 ps rms. Other performance characteristics are a readout noise of approximately 115 e- rms and an upper dynamic range of 310,000 e-.
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Summary

A 64 x 64-pixel test circuit was designed and fabricated in 0.18- m CMOS technology for investigating high-speed imaging with large-format imagers. Several features are integrated into the circuit architecture to achieve fast exposure times with low-skew and jitter for simultaneous pixel snapshots. These features include an H-tree clock distribution...

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A 64 x 64-pixel CMOS test chip for the development of large-format ultra-high-speed snapshot imagers

Geiger-mode quad-cell array for adaptive optics

May 7, 2008
  |
Conference Paper
Author:
Brian F. Aull
…
Published in:
CLEO-QELS, 2008 Conf. on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conf., 4-9 May 2008.
Topic:
optics
R&D area:
R&D group:

Summary

We report an array of Shack-Hartmann wavefront sensors using high-fill-factor Geiger-mode avalanche detector quad cells hybridized to all-digital CMOS counting circuits. The absence of readout noise facilitates fast wavefront sensing at low light levels.
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Summary

We report an array of Shack-Hartmann wavefront sensors using high-fill-factor Geiger-mode avalanche detector quad cells hybridized to all-digital CMOS counting circuits. The absence of readout noise facilitates fast wavefront sensing at low light levels.

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Geiger-mode quad-cell array for adaptive optics

The orthogonal-transfer array: a new CCD architecture for astronomy

June 21, 2004
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Conference Paper
Author:
Barry E. Burke
…
Published in:
SPIE Vol. 5499, Optical and Infrared Detectors for Astronomy, 21 June 2004, pp. 185-192.
Topic:
optics
R&D area:
R&D group:

Summary

The orthogonal-transfer array (OTA) is a new CCD architecture designed to provide wide-field tip-tilt correction of astronomical images. The device consists of an 8..8 array of small (~500x500 pixels) orthogonal-transfer CCDs (OTCCD) with independent addressing and readout of each OTCCD. This approach enables an optimum tip-tilt correction to be applied independently to each OTCCD across the focal plane. The first design of this device has been carried out at MIT Lincoln Laboratory in support of the Pan-STARRS program with a collaborative parallel effort at Semiconductor Technology Associates (STA) for the WIYN Observatory. The two versions of this device are functionally compatible and share a common pinout and package. The first wafer lots are complete at Lincoln and at Dalsa and are undergoing wafer probing.
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Summary

The orthogonal-transfer array (OTA) is a new CCD architecture designed to provide wide-field tip-tilt correction of astronomical images. The device consists of an 8..8 array of small (~500x500 pixels) orthogonal-transfer CCDs (OTCCD) with independent addressing and readout of each OTCCD. This approach enables an optimum tip-tilt correction to be applied...

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The orthogonal-transfer array: a new CCD architecture for astronomy

High-fill-factor, burst-frame-rate charge-coupled device

August 3, 2003
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Conference Paper
Author:
Robert K. Reich
…
Published in:
SPIE Vol. 5210, Ultrahigh- and High-Speed Photography, Photonics, and Videography, 3-8 August 2003, pp. 95-104.
Topic:
electronics
R&D area:
R&D group:

Summary

A 512x512-element, multi-frame charge-coupled device (CCD) has been developed for collecting four sequential image frames at megahertz rates. To operate at fast frame rates with high sensitivity, the imager uses an electronic shutter technology developed for back-illuminated CCDs. Device-level simulations were done to estimate the CCD collection well spaces for sub-microsecond photoelectron collection times. Also required for the high frame rates were process enhancements that included metal strapping of the polysilicon gate electrodes and a second metal layer. Tests on finished back-illuminated CCD imagers have demonstrated sequential multi-frame capture capability with integration intervals in the hundreds of nanoseconds range.
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Summary

A 512x512-element, multi-frame charge-coupled device (CCD) has been developed for collecting four sequential image frames at megahertz rates. To operate at fast frame rates with high sensitivity, the imager uses an electronic shutter technology developed for back-illuminated CCDs. Device-level simulations were done to estimate the CCD collection well spaces for...

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High-fill-factor, burst-frame-rate charge-coupled device
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