Transcript ppt
LSST Camera Detector Status
Sensor development on the schedule critical path
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High QE to 1000nm
• Thick silicon - 100µm thick and BB AR
coating
PSF << 0.7” (0.2”)
• High resistivity substrate (> 5
kohm∙cm)
• Small pixel size (0.2” = 10 µm)
Fast f/1.2 focal ratio
• Sensor flatness < 5µm p-v
• Package with piston, tip, tilt adj. to
~1µm
Wide FOV
• ~ 3200 cm2 focal plane
• > 189 Science-sensor mosaic
High throughput
• > 90% fill factor
• 4-side buttable package, sub-mm
gaps
Fast readout (1 s)
• Segmented sensors - ~3200 total
output ports
• 150 I/O connections per sensor
Low read noise
• < ~ 5 rms electrons
R&D Program
• Funding secured by Keck Foundation to
keep development moving.
• Three phase development - Study phase
sensor evaluation begun at BNL
• Prototype phase: Contracts with two vendors
signed
Multi-port 4K x 4K = 16M Pixel CCD
Detail of output port
Detail of one edge
July 7, 2008
J. Geary, “LSST Strawman CCD Design”, Dec. 2004
SLAC Annual Program Review
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Sensor development plan
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Technology study
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Prototype
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understand and model device characteristics
engage qualified vendors
address the most pressing technical challenges early
establish test lab at BNL
multivendor competition
fabricate sensor meeting all LSST specifications
demonstrate yield and quality control
ramp up test capability within LSST collaborating institutions
Production
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manufacture, test, and deliver 200+ science-grade sensors
24-month production period
single- or dual-source
2004
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2008
2009
2010
2011
2012
2013
2014
Modeling and
trade studies
Technology Study
3 Vendors
Prototypes
2 Vendors
DOE MIE Funding
Sensor procurement starts
July 7, 2008
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BNL and sensor group are providing leadship
for schedule driven sensor development
• Request for proposals for
prototype science CCDs
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– contract award June/July 2008
• 5 high-resistivity, thick CCDs
from study program have
been extensively characterized
– design models validated
– behavior of dark current, quantum efficiency, and
point spread function vs. thickness, temperature,
and electric field
– flatness and surface morphology
– antireflection coating
-50V
• CCD controllers for 4 new test labs under
construction
– UC Davis, SLAC, Paris, Purdue
– allows full-speed testing of segmented sensors
• Components for CCD/electronics chain testing
in assembly
X-ray images
-10V