Electronics power. FPA electronics heat load Revised for 144 fixed filter CCDs.
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Transcript of Electronics power. FPA electronics heat load Revised for 144 fixed filter CCDs.
Electronics power
FPA electronics heat load
CCD FET 12.5 mW [email protected] R 12.5 mW [email protected]
Line driver 25 mW 1mA@10V (load remoted)corners 4CCDs 144Total 29 W 2.62 W avg ovr day (200 s exposure; 20 s read)
Revised for 144 fixed filter CCDs.
CCD Power
Number of CCDs NCCD 144 CCD pixel size (horizontal) NHOR 1660Number of corners readout NCORNER 4 CCD pixel size (vertical) NVER 1660Number of ADCs NADC 576 CCD readout time TREAD 13.78 sReadout frequency FREAD 5.E+04 Hz Duty cycle (200s expose) DUTY 0.06ADC sampling frequency FADC 5.E+04 HzCCD clock power voltage VCLK 10 V
Item Peak W Idle W Avg WCCD clock line capacitance 2.50E-008 0.0000 F CCD line clock power 0.033 0.000 0.00CCD serial capacitance 4.00E-011 0.0000 F CCD serial clock power 0.346 0.00 0.02CCD MOSFET 0.0250 0.0000 W CCD MOSFET 14.400 0.000 0.93CCD output driver power 0.0500 0.0000 W CCD output power 28.80 0.00 1.86
FPA total 43.58 0.00 2.81
CDS power per CCD channel 0.0600 0.0100 W CDS 34.56 5.76 7.62ADC power 0.0100 0.0001 W ADC 5.76 0.06 0.43Control 0.2000 0.0500 W Control 28.80 7.20 8.59
Total 156.28 13.02 22.25
HgCdTe Power
Number of HgCdTe NNIR 44Number of corners read NCNIR 4
Item Peak W Idle W Avg WMux power 0.0020 0.0020 W Mux power 0.35 0.35 0.35ADC power 0.0100 0.0100 W ADC 1.76 1.76 1.76
Total 2.11 2.11 2.11
Assume the devices are constantly being read out.
LBNL CCD development
CCD Technology
LBNL 2k x 2k
First large format CCD made at LBNL
2k x 2k, 15 m pixels.
1980 x 800, 15 m pixels.
LBNL 2k x 4k
USAF test pattern.
1478 x 478410.5 m
1294 x 418612 m
2k x 4k15 m
Commercial 2k x 4k
Includes
1) 982 x 935 (15 m)2
2) 1230 x 1170 (12 m)2
3) 1402 x 1336 (10.5 m)2
4) 1636 x 1560 (9 m)2
5) 25202 (12 m)2
6) 28802 (10.5 m)2
7) 2048 x 4096 (15 m)2
8) 5122 & 1024 x 512 (15 m)2
Amplifier studies (noise)9) 1200 x 600 (15 m)2 2-
stage amplifiers for high-speed readout
Front illuminated
Noise measurements (Lot 75091, 512 x 512)
Noise vs DCS Integration Time75091.1.6.ul
0.000.501.001.502.002.503.003.504.004.505.00
3.5 4.5 5.5 6.5 7.5 8.5 9.5
DCS Integration Time (us)
Noi
se [e
- rms]
Erasure of persistence images
Flood exposure Erase
2k x 2k @ -150C
1
10
100
1000
10000
0 2 4 6 8 10 12 14 16 18
Time [hrs]
Dar
k cu
rrent
[e- /p
ixel
-hr]
Top of arrayBottom of array
Linearity and Well Depth
• Saturation curve obtained by plotting peak projected spot intensity versus exposure time.
• Full-well capacity in electrons obtained by scaling ADU’s by CCD gain.
• 15 m pixels•Well depth about 170 ke•Linearity is about 0.3%.
• Well depth is a function of pixel size (preliminary).
• 12 m well depth found to be 150 ke.•10.5 m well depth found to be 150 ke.
Measured Charge Capacity for 1100x800 CCD with 15 m Pixels
0
20000
40000
60000
80000
100000
120000
140000
160000
180000
200000
0 0.5 1 1.5 2 2.5 3
Exposure Time (sec)C
harg
e pe
r Pix
el (e
-)
LBNL 2k x 2k Quantum Efficiency
Quantum Effi ciency of state-of -the-art CCDs
0
10
20
30
40
50
60
70
80
90
100
300 400 500 600 700 800 900 1000 1100
Wavelength (nm)
Qua
ntum
Effi
cienc
y (%)
LBNLMIT/LL high rhoMarconi
From “An assessment of the optical detector systems of the W.M. Keck Observatory,”J. Beletic, R. Stover, K Taylor, 19 January 2001.
LBNL CCDs in action
LBNL 2k x 2k results
Image: 200 x 200 15 m LBNL CCD in Lick Nickel 1m.Spectrum: 800 x 1980 15 m LBNL CCD in NOAO KPNO spectrograph.Instrument at NOAO KPNO 2nd semester 2001 (http://www.noao.edu)
LBNL CCD’s at NOAO
See September 2001 newsletter at http://www.noao.edu
1) Near-earth asteroids2) Seyfert galaxy black holes3) LNBL Supernova cosmology
Cover picture taken at WIYN 3.5mwith LBNL 2048 x 2048 CCD(Dumbbell Nebula, NGC 6853)
Science studies to date at NOAO usingLBNL CCD’s:
Blue is H-alphaGreen is DIII 9532ÅRed is HeII 10124Å.
LBNL Supernova Spectrum at NOAO
Radiation damage studies
Two set of four devices each.Both sets have notch implant in serial registers.Only one set has notch implant in parallel register.Radiation doses are 5, 10, 50, and 100 x 109 protons/cm2 at 12 MeV.Note, 1x109 protons/cm2 @ 12 MeV is 1.5x107 MeV/g NIEL.
CTE vs proton flux
CTE vs Radiation Dose
0.999550.999600.999650.999700.999750.999800.999850.999900.999951.00000
0 2 4 6 8 10Dose (1010Protons/cm2)
CTE
Parallel CTESerial CTE
CTE is measured using the 55Fe X-ray method at 128 K. The readout speed is 30 kHz, the X-ray density is 0.015/pixel.
Improved Radiation Tolerance on “notch” implant devices
Parallel CTE vs Radiation Dose
0.999550.999600.999650.999700.999750.999800.999850.999900.999951.00000
0 2 4 6 8 10
Dose (1010Protons/cm2)
CTE
Standard CCDNotch CCD
CTE Dependence on Temperature
CTE vs Temperature
0.999550.999600.999650.999700.999750.999800.999850.999900.999951.00000
100 120 140 160 180 200 220
Temperature (K)
CTE
serial CTEparallel CTE
Dark Current Degradation
Dark Current vs Radiation DoseTemperature = 128 K
0
1
2
3
4
5
6
7
8
9
0 2 4 6 8 10 12Radiation Dose (1010 protons/cm2 @ 12 MeV)
Dar
k C
urre
nt (e
- / hr
)
Dark Current vs Temperature
Dark Current vs Temperaturefor CCD after 5x109 protons/cm2
0.1
1
10
100
1000
10000
100000
50 60 70 80 90 100
1/kT (eV)
Dar
k C
urre
nt (e
- /h)
-0.609 eV
208K
158KkTe 2/218.1
Fit gives expected Si bandgap, so no new dark current sources are developing.The plateau at right is not identified yet, but could be surface leakage currents.
Comparison to Conventional CCDs converted to NIEL dose
0.999000.999100.999200.999300.999400.999500.999600.999700.999800.999901.00000
0 200 400 600 800 1000 1200 1400 1600Dose (106MeV/g)
CTE
LBNL CCDLBNL Notch CCDMarconi [1]Tektronix [2]
•P-channel high-resistivity CCDs show better radiation tolerance against CTE degradation than n-channel devices.
•Dark current remains low even after proton doses equivalent to decades in space.
Packaging
Developing a solution common for ground and space telescopes
CCD Outline
Glue
Glue
PCB
Invar/Moly/AlN base
Si Detector
Connector
Wirebonds
• Support CCD• Connection to cold plate• Four-side abuttabe for dense mosaic.• Built-in mechanical precision – no shimming.• Access to bonding pads• Local electronics• Cable connector• Low mechanical stress in silicon from -150 C to +150 C.• Low background radiation materials• Low chemical reactivity with silicon
Assembly fixture
Optically polished Mo base plate.
Precision Mo spacers defining mount base to CCD optical surface.
Vacuum chuck for CCD Cam to lower CCD onto mount
EA9361 epoxy is stenciled onto mount as an array of dots.Final epoxy thickness is ~500 microns; established from measurements of epoxy characteristics and need to reduce shear transfer into silicon due to differential CTE.
Weight can be applied here if needed.
Packaging prototypes
First back-illuminated image with new mount.CCD is engineering grade used for assembly practice.
2k x 2k back-illuminated mount.2k x 4k mount similar, extending along wire-bond edge.
HgCdTe
Molecular Beam Epitaxy HgCdTe on CdZnTe• High volume, production level process• Large area uniformity• In-situ compositional control• Advanced double-layer planar heterostructure (DLPH)
p-Type ArsenicImplanted Region
HgCdTe buffer layer
MWIR absorber layer (In doped)
SWIR cap Layer
CdTe passivant
n-MWIR HgCdTe
(211) CdZnTe
Lattice matched substrate
Superior surface passivation
SNAP Visit 04-02-01 Rockwell Competition Sensitive
HAWAII-2RG Preliminary Design Highlights• 0.25m design rules, 5-metal, 1-poly• 3-side close buttable• 1, 4, or 32 outputs
– 2048 x 2048, 512 x 2048, or 64 x 2048– 5MHz option available
• Bi-directional register to allow corner to center scanning• Reference output and internal reference columns/rows• Guide window output
– Fully selectable guide window within 2048 x 2048 architecture– Seamless guide mode/science mode readout
• Read noise ~ 10 e- rms CDS; ~ 3 e- rms multiply sampled
SNAP Visit 04-02-01 Rockwell Competition Sensitive
Substrate Removal on IR SCAsObjective : Develop technology for large format SCAs with high thermal cycling
reliability, visible response, and NGST-class performance
Accomplishments To Date:
• Demonstrated on 256x256, 640x480, and 1024x1024 SCAs
• Visible light detection
• D*, NEI remain identical before and after removal
Accomplishments To Date:
• Demonstrated on 256x256, 640x480, and 1024x1024 SCAs
• Visible light detection
• D*, NEI remain identical before and after removal
Substrate (CdZnTe)Epilayer (HgCdTe)
1) Thin substrate (lap) leaving 100 microns
2) Chemical etch removing substrate3) AR coat
Si multiplexer
SNAP Visit 04-02-01 Rockwell Competition Sensitive
Substrate-removed HgCdTe SCAs Shows Good QE and Uniformity from 0.4 to 2.0 µm
0
10000
20000
30000
40000
50000
60000
0 .00 0 .20 0.40 0.60 0.80 1.00
Q E a t 500 n m
Num
ber o
f Pix
els
95% o f p ixe ls c ou n ted
0
0 .2
0 .4
0 .6
0 .8
1
4 0 0 9 0 0 1 4 0 0 1 9 0 0 2 4 0 0
W a v e le n g th (n m )
QE
0
0 .2
0 .4
0 .6
0 .8
1
4 0 0 9 0 0 1 4 0 0 1 9 0 0 2 4 0 0
W a v e le n g th (n m )
QE
0
0 .2
0 .4
0 .6
0 .8
1
4 0 0 9 0 0 1 4 0 0 1 9 0 0 2 4 0 0
W a v e le n g th (n m )
QE
• Q uantum E ffic iency o f FP A good through v is ib le
• D etectiv ity at 295K indicates R oA ~4000 O hm -cm 2
• D etectiv ity actually im proved afte r substra te rem oval and anodization
• Q uantum E ffic iency o f FP A good through v is ib le
• D etectiv ity at 295K ind icates R oA ~4000 O hm -cm 2
• D etectiv ity actually im proved after substra te rem oval and anod iza tion
HgCdTe dark current and readnoise
Per D. Hall and J. Garnett, MBE dark current at 140K is 0.02 e-/s/pixel.
Read noise per Rockwell~ 10 e- rms CDS; ~ 3 e- rms multiply sampled
SNAP fixed filter focal plane study
Focal plane is kept at fixed orientation to observation fields for 3-month periods.
Focal plane is striped through 1o x 10o field, one north and one south.
UNITCELL
FPAGROWTH
Q1
Q2
Q3
Q4
3-month rotation
1O X 10O
SNAP FIELD
TMA62 optics
I use TMA62 in the following examples.
Per Mike Lampton:
Focal length to 21.66 meters
Rinner = 0.006 radians = 0.3438 deg = 129.120 mm
Router = 0.013 radians= 0.7449 deg= 283.564 mm
Annular sky area = 1.37 sq deg
900 symmetry
6+4 filter scheme
0.0 0.5 1.0 1.5 2.0
Wavelength (m)
m)
m)
zB
center
zV
center
zR
center0.440 0.110 0.000.509 0.127 0.160.589 0.147 0.34 0.080.682 0.170 0.55 0.25 0.050.789 0.197 0.79 0.44 0.210.913 0.228 1.07 0.67 0.401.010 0.250 1.30 0.85 0.551.198 0.250 1.72 1.19 0.841.385 0.250 2.15 1.54 1.131.573 0.250 2.57 1.88 1.42
1+z scaled CCD filtersFixed width HgCdTe filtersCCDs intra-overlap 45% HgCdTe intra-overlap 25%CCD and HgCdTe overlap from 900 nm to 1000 nm
S/N calculation
)EN(RNNc
DC)GQEZ(QENSQEbSQE/SNRa
T
] c T[baN
pix
pix22
2
2exp
expexp
)(
)EN(RNN NDC) NGQENZQENS(QETNSQETN
SNRpixpixpixpix
22expexpexp
2expexp2 )(
summation in pixels of number Nexposures of number N
time exposure Tthroughput opticalQE
noise selectronic CCD-post ENnoise read CCD RN
pixel percurrent dark DCpixel per flux galaxyhost G
pixel per flux zodiacal Zflux source S
pix
exp
exp
Optimize Nexp and Texp for a few realistic cases of Npix , DC, and RN.
Note: for now, I lump RN and EN together.
ZNSSQETN
ZN(SQETNSQETN
SNRpixpix
2expexp
expexp
2expexp2
))(For an illustrative simplification,
set G=DC=RN=EN=0:
S/N weights
z CCD HgCdTe
area dilation area dilation
0.1 1 1
0.2 1 1
0.3 1 1
0.4 1 1
0.5 1 1
0.6 1 1
0.7 1 1
0.8 1 1
0.9 1 1 2 2
1.0 1 1 2 2
1.1 2 2
1.2 2 2
1.3 2 2
1.4 2 2
1.5 2 2
1.6 2 2
1.7 2 2
Weights
Let’s make each HgCdTe filter have twice the effect area of a CCD.
Let’s take advantage of time dilation for higher z objects.Individual measurements made for a z 0 object every 4 days are equivalent to the co-added measurements from two consecutive 4-day periods for a z 1 object.
S/N obtained for Texp = 200 s with weights
0
10
20
30
40
50
60
70
80
90
100
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8z
S/N
0.00.51.02.02.53.8
Fixed filter summary
0.34 sq. deg. in 144 CCDs0.34 sq. deg. In 36 HgCdTe (excluding ancillary ones)0.53 Gpixel
For 20 fields:
1150 SNe/yr with z < 1.2 780 SNe/yr with z > 1.2
Photometry time is 5350 hrs for 200 second exposures and 20 seconds readout time.Spectroscopy time is 3060 hrs (Jay’s R=150, S/N=10).
8410 hrs used out of 8760 available.
(Results above have to be derated by orbit inefficiencies.)
Fewer pixels and constant exposure time reduces telemetry BW to 25 Mbs DC and requires very little buffer memory.
CCD support electronics
•CDS – Correlated Double Samples is used for readout of the CCDs to achieve the required readout noise.Programmable gain receiver, dual-ramp architecture, and ADC buffer. HgCdTe compatible.
•ADC – 16-bit, 100 kHz equivalent conversion rate per CCD (could be a single muxed 400 kHz unit).
•Sequencer – Clock pattern generator supportingmodes of operation: erase, expose, readout, idle.
•Clock drivers – Programmable amplitude andrise/fall times. Supports 4-corner or 2-cornerreadout.
•Bias and power generation – Provide switched, programmable large voltages for CCD and local power.
•Temperature monitoring – Local and remote.
•DAQ and instrument control interface – Path to data buffer memory, master timing, and configuration and control.
Readout Electronics Concept
LBNL has a long history in rad hard ASIC design for high energy physics.• We have submitted a CDS to DMILL.• We have simulated 0.8 m and 0.25 m CMOS implementations.
Timely developments in the commercial realm is work on HV sub-micron processes for flat panel displays may make a single chip solution possible.
CDS ASIC
Data
Controls
Data Acquisition
LBNL ASIC capabilities
LBNL Electronics Engineering
• Instrumentation systems• IC design (Analog/Mixed/digital)
• Boards design(Analog/Mixed/digital)
• Control systems
IC capabilities• Multi channel low noise sensor
readout integrated circuits (ICs)— Full custom— Automated Place&Route
• ICs for harsh environment— Up to 50 Mrad
• ICs for Particle detection• ICs for Photon detection• ICs for Imaging
Deployed IC list
• Elefant (wire drift chamber)• Atom (Si detectors)• AWTD (PMT)• SVX 1-3 (Si detectors)• WTA (Pet Photo diodes)• QMUX (Amorphous Si Xray)• CDS (Si CCD)
Café-M (Si detectors) ABC (Si detectors) Star (TPC 2 chips) Pixel (Si detectors) FPPA (Si APD) CTRL (Si APD) Arapix64 (Si photo
detector)
IC design tools
• Cadence— State of the art IC design tool
• Mentor— State of the art IC design tool— State of the art PC board design tools— State of the art system design tools
• Simulators— Hspice— Eldo— XL verilog — Quicksim
IC processes used by LBNL
• TSMC0.25m CMOS, radiation hard by design technique <50Mrad
• IBM0.25m CMOS, radiation hard by design technique <50Mrad
• XFAB 0.6 m radiation soft CMOS
• Honeywell0.8 m radiation hard CMOS
Peregrine0.5 m radiation hard CMOS
IntersilUHFIX, Comp. Bipolar high speed process. Rad. Tol. < 300krad, ft=2.5GHz
DMILL0.8 m radiation hard BiCMOS
HP0.5 m radiation soft CMOS0.8 m radiation soft CMOS
The Enclosed Layout Transistors (ELT)
• When exposed to an ionizing dose, CMOS technologies are affected by charge buildup and defects are created in the silicon-dioxide layers.
• Charge in the gate oxide: the effects at the transistor level are threshold voltage shift, mobility degradation, and noise increase.
• Charge buildup in the thicker field oxides opens leakage paths between source and drain of the same n-channel transistor.
• The effects in the oxide are inversely proportional to the oxide thickness and sharply decrease below about 10 to12 nm.
• How to solve: Enclosed layout of transistors in 0.25 m CMOS• 0.25m CMOS radiation hard capability:
— Gate-oxide: 5 nm thick— NMOS sensitive — PMOS not sensitive