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Back-illuminated three-dimensionally integrated CMOS image sensors for scientific applications

Published in:
SPIE Vol. 6690, Focal Plane Arrays for Space Telescopes III, 27-28 August 2007, 669009.

Summary

SOI-based active pixel image sensors have been built in both monolithic and vertically interconnected pixel technologies. The latter easily supports the inclusion of more complex pixel circuitry without compromising pixel fill factor. A wafer-scale back-illumination process is used to achieve 100% fill factor photodiodes. Results from 256 x 256 and 1024 x 1024 pixel arrays are presented, with discussion of dark current improvement in the differing technologies.
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Summary

SOI-based active pixel image sensors have been built in both monolithic and vertically interconnected pixel technologies. The latter easily supports the inclusion of more complex pixel circuitry without compromising pixel fill factor. A wafer-scale back-illumination process is used to achieve 100% fill factor photodiodes. Results from 256 x 256 and...

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Multifocal multiphoton microscopy (MMM) at a frame rate beyond 600 Hz

Published in:
Opt. Express, Vol. 15, No. 17, 20 August 2007, pp. 10998-11005.

Summary

We introduce a multiphoton microscope for high-speed three-dimensional (3D) fluorescence imaging. The system combines parallel illumination by a multifocal multiphoton microscope (MMM) with parallel detection via a segmented high-sensitivity charge-couple device (CCD) camera. The instrument consists of a Ti-sapphire laser illuminating a microlens array that projects 36 foci onto the focal plane. The foci are scanned using a resonance scanner and imaged with a custom-made CCD camera. The MMM increases the imaging speed by parallelizing the illumination; the CCD camera can operate at a frame rate of 1428 Hz while maintaining a low read noise of 11 electrons per pixel by dividing its chip into 16 independent segments for parallelized readout. We image fluorescent specimens at a frame rate of 640 Hz. The calcium wave of fluo3 labeled cardiac myocytes is measured by imaging the spontaneous contraction of the cells in a 0.625 second sequence movie, consisting of 400 single images.
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Summary

We introduce a multiphoton microscope for high-speed three-dimensional (3D) fluorescence imaging. The system combines parallel illumination by a multifocal multiphoton microscope (MMM) with parallel detection via a segmented high-sensitivity charge-couple device (CCD) camera. The instrument consists of a Ti-sapphire laser illuminating a microlens array that projects 36 foci onto the...

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Arrays of InP-based avalanche photodiodes for photon counting

Summary

Arrays of InP-based avalanche photodiodes (APDs) with InGaAsP absorber regions have been fabricated and characterized in the Geiger mode for photon-counting applications. Measurements of APDs with InGaAsP absorbers optimized for 1.06 um wavelength show dark count rates (DCRs)
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Summary

Arrays of InP-based avalanche photodiodes (APDs) with InGaAsP absorber regions have been fabricated and characterized in the Geiger mode for photon-counting applications. Measurements of APDs with InGaAsP absorbers optimized for 1.06 um wavelength show dark count rates (DCRs)

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Orthogonal transfer arrays for wide-field adaptive imaging

Published in:
Proc. 2007 Int. Image Sensor Workshop, 7-10 June 2007.

Summary

The orthogonal transfer array (OTA) is a novel charge-coupled device (CCD) imager based on the orthogonal-transfer CCD (OTCCD). The OTCCD, in turn, is a device capable of charge transfer in all directions and has been developed for adaptive imaging in ground-based astronomy. By using a bright guide star as a beacon, the OTCCD can correct for wavefront tilt due to atmospheric effects as well as compensation for telescope shake, which in turn enhances the resolution and SNR. However, for wide field-of-view imaging the atmospheric wavefront distortions decorrelate over distances more than a few 10's of arcmin and hence an array of independently driven OTCCDs is required. To resolve this issue we developed the OTA, which consists of a two-dimensional array of OTCCDs combined with addressing and control logic to enable independent clocking of each OTCCD. This device enables spatially varying electronic tip-tilt correction and was developed for the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) program at the University of Hawaii Institute for Astronomy (UH/IfA)
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Summary

The orthogonal transfer array (OTA) is a novel charge-coupled device (CCD) imager based on the orthogonal-transfer CCD (OTCCD). The OTCCD, in turn, is a device capable of charge transfer in all directions and has been developed for adaptive imaging in ground-based astronomy. By using a bright guide star as a...

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A wafer-scale 3-D circuit integration technology

Published in:
IEEE Trans. Electron Devices, Vol. 53, No. 10, October 2006, pp. 2507-2516.

Summary

The rationale and development of a wafer-scale three-dimensional (3-D) integrated circuit technology are described. The essential elements of the 3-D technology are integrated circuit fabrication on silicon-on-insulator wafers, precision wafer-wafer alignment using an in-house-developed alignment system, low-temperature wafer-wafer bonding to transfer and stack active circuit layers, and interconnection of the circuit layers with dense-vertical connections with sub-[Omega] 3-D via resistances. The 3-D integration process is described as well as the properties of the four enabling technologies. The wafer-scale 3-D technology imposes constraints on the placement of the first lithographic level in a wafer-stepper process. Control of wafer distortion and wafer bow is required to achieve submicrometer vertical vias. Three-tier digital and analog 3-D circuits were designed and fabricated. The performance characteristics of a 3-D ring oscillator, a 1024 x 1024 visible imager with an 8-um pixel pitch, and a 64 x 64 Geiger-mode laser radar chip are described.
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Summary

The rationale and development of a wafer-scale three-dimensional (3-D) integrated circuit technology are described. The essential elements of the 3-D technology are integrated circuit fabrication on silicon-on-insulator wafers, precision wafer-wafer alignment using an in-house-developed alignment system, low-temperature wafer-wafer bonding to transfer and stack active circuit layers, and interconnection of the...

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Lincoln Laboratory high-speed solid-state imager technology

Published in:
SPIE Vol. 6279, 27th Int. Congress on High-Speed Photography and Photonics, 17-22 September 2006, 62791K.

Summary

Massachusetts Institute of Technology, Lincoln Laboratory (MIT LL) has been developing both continuous and burst solid-state focal-plane-array technology for a variety of high-speed imaging applications. For continuous imaging, a 128 ¿ 128-pixel charge coupled device (CCD) has been fabricated with multiple output ports for operating rates greater than 10,000 frames per second with readout noise of less than 10 e- rms. An electronic shutter has been integrated into the pixels of the back-illuminated (BI) CCD imagers that give snapshot exposure times of less than 10 ns. For burst imaging, a 5 cm x 5 cm, 512 x 512-element, multi-frame CCD imager that collects four sequential image frames at megahertz rates has been developed for the Los Alamos National Laboratory Dual Axis Radiographic Hydrodynamic Test (DARHT) facility. To operate at fast frame rates with high sensitivity, the imager uses the same electronic shutter technology as the continuously framing 128 x 128 CCD imager. 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 ultra-short exposure times (100 to 300 ps). The detector will consist of CMOS readouts for high speed sampling (tens of picoseconds transistor switching times) that are bump bonded to deep-depletion silicon photodiodes. A 64 x 64-pixel CMOS test chip has been designed, fabricated and characterized to investigate the feasibility of making large-format detectors with short, simultaneous exposure times.
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Summary

Massachusetts Institute of Technology, Lincoln Laboratory (MIT LL) has been developing both continuous and burst solid-state focal-plane-array technology for a variety of high-speed imaging applications. For continuous imaging, a 128 ¿ 128-pixel charge coupled device (CCD) has been fabricated with multiple output ports for operating rates greater than 10,000 frames...

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Laser radar imager based on 3D integration of Geiger-mode avalanche photodiodes with two SOI timing circuit layers

Summary

We have developed focal-plane arrays and laser-radar (ladar) imaging systems based on Geiger-mode avalanche photodiodes (APDs) integrated with high-speed all-digital CMOS timing circuits. A Geiger-mode APD produces a digital pulse upon detection of a single photon. This pulse is used to stop a fast digital counter in the pixel circuit, thereby measuring photon arrival time. This "photon-to-digital conversion" yields quantum-limited sensitivity and noiseless readout, enabling high-performance ladar systems. Previously reported focal planes, based on bump bonding or epoxy bonding the APDs to foundry chips, had coarse (100um) pixel spacing and 0.5ns timing quantization.
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Summary

We have developed focal-plane arrays and laser-radar (ladar) imaging systems based on Geiger-mode avalanche photodiodes (APDs) integrated with high-speed all-digital CMOS timing circuits. A Geiger-mode APD produces a digital pulse upon detection of a single photon. This pulse is used to stop a fast digital counter in the pixel circuit...

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Megapixel CMOS image sensor fabricated in three-dimensional integrated circuit technology

Summary

In this paper a 3D integrated 1024x1024, 8um pixel visible image sensor fabricated with oxide-to-oxide wafer bonding and 2-um square 3-D-vias in every pixel is presented. The 150mm wafer technology integrates a low-leakage, deep-depletion, 100% fill factor photodiode layer to a 3.3-V, 0.35-um gate length fully depleted (FD) SOI CMOS readout circuit layer.
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Summary

In this paper a 3D integrated 1024x1024, 8um pixel visible image sensor fabricated with oxide-to-oxide wafer bonding and 2-um square 3-D-vias in every pixel is presented. The 150mm wafer technology integrates a low-leakage, deep-depletion, 100% fill factor photodiode layer to a 3.3-V, 0.35-um gate length fully depleted (FD) SOI CMOS...

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LLiST - a new star tracker camera for tip-tilt correction at IOTA

Published in:
2004 SPIE Conf. on Astronomical Telescopes and Instrumentation, 21-26 June 2004.

Summary

The tip-tilt correction system at the Infrared Optical Telescope Array (IOTA) has been upgraded with a new star tracker camera. The camera features a backside-illuminated CCD chip offering doubled overall quantum efficiency and a four times higher system gain compared to the previous system. Tests carried out to characterize the new system showed a higher system gain with a lower read-out noise electron level. Shorter read-out cycle times now allow to compensate tip-tilt fluctuations so that their error imposed on visibility measurements becomes comparable to, and even smaller than, that of higher-order aberrations.
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Summary

The tip-tilt correction system at the Infrared Optical Telescope Array (IOTA) has been upgraded with a new star tracker camera. The camera features a backside-illuminated CCD chip offering doubled overall quantum efficiency and a four times higher system gain compared to the previous system. Tests carried out to characterize the...

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

Published in:
SPIE Vol. 5499, Optical and Infrared Detectors for Astronomy, 21 June 2004, pp. 185-192.

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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