RIDL visit-1 BEB 6/24/2015 MIT Lincoln Laboratory Orthogonal-Transfer Charge-Coupled Devices and...

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RIDL visit-1 BEB 03/15/22 MIT Lincoln Laboratory Orthogonal-Transfer Charge-Coupled Devices and Low-Noise Charge-Coupled Devices Readout Circuits* Barry E. Burke *The MIT Lincoln Laboratory portion of this work was performed under a Collaboration Agreement between MIT Lincoln Laboratory and The University of Hawaii, Institute for Astronomy (IfA). Opinions, interpretations, conclusions, and recommendations are those of the authors, and do not necessarily represent the view of the United States Government.
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Transcript of RIDL visit-1 BEB 6/24/2015 MIT Lincoln Laboratory Orthogonal-Transfer Charge-Coupled Devices and...

  • Slide 1
  • RIDL visit-1 BEB 6/24/2015 MIT Lincoln Laboratory Orthogonal-Transfer Charge-Coupled Devices and Low-Noise Charge-Coupled Devices Readout Circuits* Barry E. Burke *The MIT Lincoln Laboratory portion of this work was performed under a Collaboration Agreement between MIT Lincoln Laboratory and The University of Hawaii, Institute for Astronomy (IfA). Opinions, interpretations, conclusions, and recommendations are those of the authors, and do not necessarily represent the view of the United States Government.
  • Slide 2
  • MIT Lincoln Laboratory RIDL visit-2 BEB 6/24/2015 Outline Review of Orthogonal-Transfer Charge-Coupled Devices (OTCCD) Development of the orthogonal transfer array (OTA) Low-noise CCD readout circuits Summary
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  • MIT Lincoln Laboratory RIDL visit-3 BEB 6/24/2015 Conventional vs. Orthogonal-Transfer CCDs
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  • MIT Lincoln Laboratory RIDL visit-4 BEB 6/24/2015 Application Areas Compensation of platform motion Imaging from unstable and/or moving platforms TDI (time delay and integrate) with variable scan direction Compensation of scene motion Ground-based astronomy Output register Video out Frame store Imaging area OTCCD can noiselessly compensate for scene motion across sensor during image integration
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  • MIT Lincoln Laboratory RIDL visit-5 BEB 6/24/2015 Application of OTCCDs in Astronomy Star-cluster imagery (M71) With motion compensation, =0.50 SNR increase: 1.7 Use OTCCD to remove blurring due random motion of star images (electronic tip-tilt) No motion compensation, =0.73"
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  • MIT Lincoln Laboratory RIDL visit-6 BEB 6/24/2015 Outline Review of Orthogonal-Transfer Charge-Coupled Devices (OTCCD) Development of the orthogonal transfer array (OTA) Low-noise CCD readout circuits Summary
  • Slide 7
  • MIT Lincoln Laboratory RIDL visit-7 BEB 6/24/2015 Pan-STARRS (Panoramic Survey Telescope and Rapid Response System) Proposed Pan-STARRS telescope configuration Gigapixel focal-plane array (64 CCDs) Four 1.8-m telescopes viewing same sky sector 3 FOV, 24 m v sensitivity High-cadence, wide-field surveys Detect variable or moving objects 1.4-Gpixel CCD focal-plane array on each telescope First Pan-STARRS telescope on Haleakala (PS1)
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  • MIT Lincoln Laboratory RIDL visit-8 BEB 6/24/2015 Orthogonal-Transfer Array Wide field-of-view (FOV) imaging Wavefront tilt decorrelates over FOV > few arc minutes Need 2D array of OTCCDs, each independently clocked to track local wavefront tilt (rubber focal plane) OTA is a new CCD architecture Requires on-chip switching logic More complex layout and processing than conventional CCDs 2.38 arc min
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  • MIT Lincoln Laboratory RIDL visit-9 BEB 6/24/2015 Orthogonal Transfer Array New device paradigm 2D array of independent OTCCDs Independent clocking and readout of OTCCDs Advantages Enables spatially varying tip-tilt correction Isolated defective cells tolerable (higher yield) OTA: 8 8 array of OTCCD cells OTA cell with I/O control Four-phase OTCCD pixels
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  • MIT Lincoln Laboratory RIDL visit-10 BEB 6/24/2015 OTA Operation Subset (4 5) of cells chosen to image guide stars Map of wavefront tilt constructed from guide-star data and applied to science cells Four redundant views of every patch of sky used to fill gaps due to Guide-star cells Dead cells Cosmic rays Dead areas between cells and devices
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  • MIT Lincoln Laboratory RIDL visit-11 BEB 6/24/2015 Device Fabrication Four OTAs on 150-mm wafer (die size 49.5 50.1 mm) Four-poly, n-buried-channel process Fabricated on 5 000 cm float- zone silicon wafers Back-illuminated devices thinned to 75 m 150-mm wafer with four OTAs Photo of pixel array
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  • MIT Lincoln Laboratory RIDL visit-12 BEB 6/24/2015 Sample Imagery First devices were fully functional but with some issues (noise, logic glow) Device redesign resolved issues with prototype devices Redesigned devices have been fabricated and most of them packaged Image from back-illuminated OTA 10-m pixel, 22.6 Mpixels Image from OTA cell with fixed light spot and CCD gates clocked
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  • MIT Lincoln Laboratory RIDL visit-13 BEB 6/24/2015 Substrate Bias Substrate bias enables thick, fully depleted devices: High quantum efficiency, 800-1000 nm Small charge point-spread function
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  • MIT Lincoln Laboratory RIDL visit-14 BEB 6/24/2015 Quantum Efficiency Back-surface p + using ion-implant/laser anneal Two-layer anti-reflection coating with reflection null at 850 nm for reduced fringing Thicker device clearly superior beyond 800 nm
  • Slide 15
  • MIT Lincoln Laboratory RIDL visit-15 BEB 6/24/2015 OTA Focal Planes TC3 focal plane assembled from 16 prototype devices; on-sky tests in February GPC1 assembled from lots 2 and 3 (summer 2007)
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  • MIT Lincoln Laboratory RIDL visit-16 BEB 6/24/2015 Outline Review of Orthogonal-Transfer Charge-Coupled Devices (OTCCD) Development of the orthogonal transfer array (OTA) Low-noise CCD readout circuits Summary
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  • MIT Lincoln Laboratory RIDL visit-17 BEB 6/24/2015 CCD Output Circuits
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  • MIT Lincoln Laboratory RIDL visit-18 BEB 6/24/2015 Output Circuit Comparison Sense-node capacitance is lower ( higher responsivity) for JFET than MOSFET Noise spectral voltage is lower for JFET than MOSFET
  • Slide 19
  • MIT Lincoln Laboratory RIDL visit-19 BEB 6/24/2015 Noise Comparison Best MOSFET noise vs. preliminary JFET noise 2000-fps, 160 160-pixel imager, 20 ports with JFET output circuits
  • Slide 20
  • MIT Lincoln Laboratory RIDL visit-20 BEB 6/24/2015 Summary OTCCD developed for astronomical applications but has a potentially much broader range of uses OTA development for Pan-STARRS is new OTCCD concept, also with other applications Recent work with JFETs shows noise levels better than BCMOSFETs and nearing 1 e -