Single Event Effects on Commercial SRAMs and Power MOSFETS ... · v Upsets mapped to the proton...
Transcript of Single Event Effects on Commercial SRAMs and Power MOSFETS ... · v Upsets mapped to the proton...
Work supported by USAF/Space Division, DSWA & NASA/HQ
Single Event Effects on CommercialSRAMs and Power MOSFETS:
Final Results of the CRUX FlightExperiment on APEX
Janet L. BarthNASA/Goddard Space Flight Center
John W. AdolphsenUNISYS, Inc.
and
George B. GeeSGT, Inc.
Work supported by USAF/Space Division, DSWA & NASA/HQ
The CRUX* Experiment
u Single Event Effects Experiment: Flight test of commercial devices» 1 Mbit & 256 Kbit SRAMs» 100 volt & 200 volt Power MOSFETs» Objective: Validate and/or improve prediction models
u Flew on Air Force APEX** satellite, August 1994 to May 1996(Solar Minimum)
u Inclination: 70º, Altitude: 362 x 2,544 kmu Environment was measured by CREDO Instrument [Ref. 1]
» Total dose at 10 locations in the experiment» LET of particles in different channels up to 30 MeV/(mg-cm2)
u 3-D model of APEX satellite and CRUX box was used to evaluate theradiation exposure at each Device Under Test (DUT) location
u Previously published papers reported preliminary results [Ref. 2, 3, & 4]
* Cosmic Ray Upset Experiment** Advanced Photovoltaic and Electronics Experiment
Work supported by USAF/Space Division, DSWA & NASA/HQ
Devices Flown on CRUX
Part Type Manufacturer Technology Chip Size # ofDevices
Total Bits
MT5C1008-CW25 MICRON NMOS/CMOS 128K x 8 23 24,117,248
88130L45PC EDI NMOS/CMOS 128K x 8 9 9,437,184
ZQ04054628128 HITACHI/ELMO NMOS/CMOS 128K x 8 16 16,777,216
MT5C2568-CW25 MICRON CMOS 32K x 8 40 10,485,760
8832C12C1 EDI CMOS 32K x 8 18 4,718,592
71256L100DB IDT NMOS/CMOS 32K x 8 19 4,980,736
Part Type Manufacturer Technology MaximumVoltage D-S
# ofDevices
2N6796 Harris N-channel 100 12
2N6796 IR N-channel 100 12
2N6798 Harris N-channel 200 12
2N6798 IR N-channel 200 12
Power MOSFET Devices on CRUX
SRAM Devices on CRUX
Work supported by USAF/Space Division, DSWA & NASA/HQ
Summary of Previous Results:First 262 Days of Mission
u 1 Mbit & 256 Kbit SRAMs (See Ref. 2 & Ref. 3)» During quiet magnetospheric and solar conditions, protons dominated the single event upset
(SEU) rates.v Upsets mapped to the proton belts.v 98% of the upsets occurred in regions where the dipole shell parameter (L) < 3 even though APEX spent
only 38% of its time there.
» Use of non-flight lot test data can lead to large errors in predicting upset rates.» EDI 256K and MICRON 1M devices showed very large variations in the upset rate when
comparing individual DUTs.» MICRON 1M devices showed extreme upset sensitivity to programmed logic state.» 35 multiple bit upsets were observed on the HITACHI/ELMO 1M devices and one multiple was
observed on a MICRON 256K device.» Stuck bit errors were observed on all part types except the MICRON 1M.
u 100 volt & 200 volt Power MOSFETs (See Ref. 4)» 3 Single Event Burn-outs (SEBs) were observed on the 100 volt Power MOSFETs.» 205 SEBs were observed on the 200 volt Power MOSFETs.» SEBs on the 200 volt Power MOSFETs were dominated by trapped protons.» Rate of SEBs increases with increase in the drain-to-source voltage.» There are threshold voltages below which SEBs do not occur.» For protons, predicted SEB rates based on ground tests showed excellent agreement with
observed flight rates. (See Ref. 5)
Work supported by USAF/Space Division, DSWA & NASA/HQ
Final CRUX Results: 20 Months of Data
u 11 Months of data were added to theCRUX data set.
» Improved statistics on the single eventeffects rates, especially multiple bitupsets (MBUs) and single hard errors(“stuck bits”).
» Improved coverage of the radiationbelts.
u The figure at right shows theprecession of the latitude of perigee ofthe orbit as a function of days fromlaunch.
u The vertical line on figure marks theend of data coverage for the firstanalysis.
0 100 200 300 400 500 600 700
Time (Mission days)
-80
-60
-40
-20
0
20
40
60
80
Per
igee
Lat
itude
(deg
)
Variation in Latitude of PerigeeAPEX Orbit: I=70 deg, H=362/2544 km, Period = 115 min.
Spacecraft in Safehold
Day Data Only
Maximum proton fluence exposure occurs whenlatitude of perigee is at the magnetic equator.
Work supported by USAF/Space Division, DSWA & NASA/HQ
Upset Rates: Altitude = 650-750 km
u Upset data were binned in altitude.u These plots show upset rates for a low
earth orbit.u Most upsets occur in the South Atlantic
Anomaly (SAA).u Upsets at higher inclinations are
induced by cosmic ray heavy ions.
-180 -150 -120 -90 -60 -30 0 30 60 90 1 2 0 1 5 0 180
Long i tude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
M ic ron 256k :A l t i t ude :650km - 750km
1.0E-7 to 5 .0E-75 .0E-7 to 1 .0E-61 .0E-6 to 5 .0E-65 .0E-6 to 1 .0E-51 .0E-5 to 5 .0E-55 .0E-5 to 1 .0E-41 .0E-4 to 5 .0E-45 .0E-4 to 1 .0E-31 .0E-3 to 5 .0E-3
Upsets /B i t /Day
-180 -150 -120 -90 -60 -30 0 30 60 90 120 150 180
Long i tude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
Hi tach i 1M:A l t i t ude :650km - 750km
1.0E-7 to 5 .0E-75 .0E-7 to 1 .0E-61 .0E-6 to 5 .0E-65 .0E-6 to 1 .0E-51 .0E-5 to 5 .0E-55 .0E-5 to 1 .0E-41 .0E-4 to 5 .0E-45 .0E-4 to 1 .0E-31 .0E-3 to 5 .0E-3
Upsets /B i t /Day
-180 -150 -120 -90 -60 -30 0 30 60 90 120 150 180
Longitude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
M icron 1M:Al t i tude:650km - 750km
1.0E-7 to 5.0E-75.0E-7 to 1.0E-61.0E-6 to 5.0E-65.0E-6 to 1.0E-51.0E-5 to 5.0E-55.0E-5 to 1.0E-41.0E-4 to 5.0E-45.0E-4 to 1.0E-31.0E-3 to 5.0E-3
Upsets/Bit /Day
Work supported by USAF/Space Division, DSWA & NASA/HQ
Upset Rates: Altitude = 1250-1350 km
u Increasing the altitude by 600 kmincreased the upset rate 8 to 11 times.
u The increased rate is due to theincrease in the size of the SAA and,also, the increase in the levels of highenergy protons.
u At this altitude, the higher upset rate onthe MICRON 256K devices is evident.
-180 -150 -120 -90 -60 -30 0 30 60 90 120 150 180
Longitude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
M icron 256k:Alt i tude:1250km - 1350km
1.0E-7 to 5.0E-75.0E-7 to 1.0E-61.0E-6 to 5.0E-65.0E-6 to 1.0E-51.0E-5 to 5.0E-55.0E-5 to 1.0E-41.0E-4 to 5.0E-45.0E-4 to 1.0E-31.0E-3 to 5.0E-3
Upsets/Bit/Day
- 1 8 0 - 1 5 0 - 1 2 0 - 9 0 - 6 0 - 3 0 0 3 0 60 9 0 1 2 0 1 5 0 1 8 0
L o n g i t u d e
- 9 0
- 7 5
- 6 0
- 4 5
- 3 0
- 1 5
0
1 5
3 0
4 5
6 0
7 5
9 0
Latit
ude
H i tach i 1M : A l t i t u d e : 1 2 5 0 k m - 1 3 5 0 k m
1 . 0 E - 7 t o 5 . 0 E - 75 . 0 E - 7 t o 1 . 0 E - 61 . 0 E - 6 t o 5 . 0 E - 65 . 0 E - 6 t o 1 . 0 E - 51 . 0 E - 5 t o 5 . 0 E - 55 . 0 E - 5 t o 1 . 0 E - 41 . 0 E - 4 t o 5 . 0 E - 45 . 0 E - 4 t o 1 . 0 E - 31 . 0 E - 3 t o 5 . 0 E - 3
U p s e t s / B i t / D a y
-180 -150 -120 -90 -60 -30 0 30 60 90 120 150 180
Longitude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
Micron 1M:Alt i tude:1250km - 1350km
1.0E-7 to 5.0E-75.0E-7 to 1.0E-61.0E-6 to 5.0E-65.0E-6 to 1.0E-51.0E-5 to 5.0E-55.0E-5 to 1.0E-41.0E-4 to 5.0E-45.0E-4 to 1.0E-31.0E-3 to 5.0E-3
Upsets/Bit/Day
Work supported by USAF/Space Division, DSWA & NASA/HQ
Upset Rates: Altitude = 1750-1850 km
u At this altitude, the belt structure ofthe trapped proton regions is clearlyseen.
u The upset rates have increased bya factor of 20 to 30 from the 700 kmorbit.
-180 -150 -120 -90 -60 -30 0 30 60 90 120 150 180
Longitude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
M icron 256k:Alt i tude:1750km - 1850km
1.0E-7 to 5.0E-75.0E-7 to 1.0E-61.0E-6 to 5.0E-65.0E-6 to 1.0E-51.0E-5 to 5.0E-55.0E-5 to 1.0E-41.0E-4 to 5.0E-45.0E-4 to 1.0E-31.0E-3 to 5.0E-3
Upsets/Bit/Day
- 1 8 0 - 1 5 0 - 1 2 0 - 9 0 - 6 0 - 3 0 0 3 0 6 0 9 0 1 2 0 1 5 0 1 8 0
L o n g i t u d e
- 9 0
- 7 5
- 6 0
- 4 5
- 3 0
- 1 5
0
1 5
3 0
4 5
6 0
7 5
9 0
Latit
ude
H i t a c h i 1 M :A l t i t u d e : 1 7 5 0 k m - 1 8 5 0 k m
1 . 0 E - 7 t o 5 . 0 E - 75 . 0 E - 7 t o 1 . 0 E - 61 . 0 E - 6 t o 5 . 0 E - 65 . 0 E - 6 t o 1 . 0 E - 51 . 0 E - 5 t o 5 . 0 E - 55 . 0 E - 5 t o 1 . 0 E - 41 . 0 E - 4 t o 5 . 0 E - 45 . 0 E - 4 t o 1 . 0 E - 31 . 0 E - 3 t o 5 . 0 E - 3
U p s e t s / B i t / D a y
-180 -150 -120 -90 -60 -30 0 30 60 90 120 150 180
Longitude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
Micron 1M:Alt i tude:1750km - 1850km
1.0E-7 to 5.0E-75.0E-7 to 1.0E-61.0E-6 to 5.0E-65.0E-6 to 1.0E-51.0E-5 to 5.0E-55.0E-5 to 1.0E-41.0E-4 to 5.0E-45.0E-4 to 1.0E-31.0E-3 to 5.0E-3
Upsets/Bit/Day
Work supported by USAF/Space Division, DSWA & NASA/HQ
Upset Rates: Altitude = 2450-2550 km
u 2500 km is near the peak of the highenergy protons regions (3000 km).
u At this altitude, the relative insensitivityof the HITACHI/ELMO 1M devices toheavy ion induced upsets is evident.
-180 -150 -120 -90 -60 -30 0 30 60 90 1 2 0 1 5 0 180
Long i tude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
M ic ron 256k :A l t i t ude :2450km - 2550km
1.0E-7 to 5 .0E-75 .0E-7 to 1 .0E-61 .0E-6 to 5 .0E-65 .0E-6 to 1 .0E-51 .0E-5 to 5 .0E-55 .0E-5 to 1 .0E-41 .0E-4 to 5 .0E-45 .0E-4 to 1 .0E-31 .0E-3 to 5 .0E-3
Upsets /B i t /Day
- 1 8 0 - 1 5 0 - 1 2 0 - 9 0 - 6 0 - 3 0 0 3 0 6 0 9 0 1 2 0 1 5 0 1 8 0
L o n g i tude
- 9 0
- 7 5
- 6 0
- 4 5
- 3 0
- 1 5
0
1 5
3 0
4 5
6 0
7 5
9 0
Latit
ude
H i t a c h i 1 M : A l t i t u d e : 2 4 5 0 k m - 2 5 5 0 k m
1 . 0 E - 7 t o 5 . 0 E - 75 . 0 E - 7 t o 1 . 0 E - 61 . 0 E - 6 t o 5 . 0 E - 65 . 0 E - 6 t o 1 . 0 E - 51 . 0 E - 5 t o 5 . 0 E - 55 . 0 E - 5 t o 1 . 0 E - 41 . 0 E - 4 t o 5 . 0 E - 45 . 0 E - 4 t o 1 . 0 E - 31 . 0 E - 3 t o 5 . 0 E - 3
U p s e t s / B i t / D a y
-180 -150 -120 -90 -60 -30 0 30 60 90 120 150 180
Longi tude
-90
-75
-60
-45
-30
-15
0
15
30
45
60
75
90
Latit
ude
M icron 1M:Al t i tude:2450km - 2550km
1.0E-7 to 5 .0E-75.0E-7 to 1 .0E-61.0E-6 to 5 .0E-65.0E-6 to 1 .0E-51.0E-5 to 5 .0E-55.0E-5 to 1 .0E-41.0E-4 to 5 .0E-45.0E-4 to 1 .0E-31.0E-3 to 5 .0E-3
Upsets/Bi t /Day
Work supported by USAF/Space Division, DSWA & NASA/HQ
Variation in Number of Upsets per DUT
u Variation within electronics box enclosure» Percentage difference from average was computed for each DUT.» Distribution of the number of upsets on individual DUTs was compared to
a Normal Distribution. The fit to a normal distribution was measured withShapiro-Wilkes parameter. A value close to .99 indicates a good fit tonormal.
u Correlation between the DUT exposure to the environment and thenumber of upsets» A 3-D Model of the APEX satellite & CRUX box was used to estimate
proton exposure at each DUT location.» The correlation between the exposure and the number of upsets on each
DUT was measured with Linear Regression fits.v r = regression coefficientv P(N,r) = probability of r being from an uncorrelated population where N is the
number of degrees of freedom
Work supported by USAF/Space Division, DSWA & NASA/HQ
MICRON 1M - 23 DUTs
5 6 7 8 9 10
Average Daily > 50 MeV Proton Fluence x 108
0
2000
4000
6000
8000
10000
12000
14000
16000
Tota
l Num
ber o
f Ups
ets
Linear Regression Fit - # of Upsets vs Device Exposure
u Total # of Upsets = 146,270u Mean = 6359, Maximum:Minimum = 10:1u Std. Dev./Mean = 52%u Fit to Normal Distribution = .941u Regression Coefficient (r) = -.08u Probability (N,r) = .70u Parameters indicate a large range in DUT
response within the flight lot.
Variation in Upset Rates per DUT in the CRUX Electronics BoxDUTs Ordered by Increasing Exposure to the Environment
b4c10
b4c9
b3c10
b3c4
b3c15
b3c8
b3c1
b4c12
b3c9
b4c14
b3c11
b3c3b3c13
b3c0b3c12
b3c6
b3c7
b3c2
b3c14b4c15
b3c5
b4c8
b4c13
-100
-80
-60
-40
-20
0
20
40
60
80
100
Per
cent
Diff
eren
ce fr
om th
e A
vera
ge
b=board #c=chip #
Distribution of DUT Upset Sensitivity
Total Number of Upsets on DUT
Num
ber o
f Ups
ets
in R
ange
0
1
2
3
4
5
6
7
8
0 2000 4000 6000 8000 10000 12000 14000
ExpectedNormal
Work supported by USAF/Space Division, DSWA & NASA/HQ
EDI 1M - 9 DUTs
5 6 7 8 9 10
Average Daily > 50 MeV Proton Fluence x 108
6400
6800
7200
7600
8000
8400
8800
9200
9600
Tota
l Num
ber o
f Ups
ets
Linear Regression Fit - # of Upsets vs Device Exposure
u Total # of Upsets = 74,154u Mean = 8239, Maximum:Minimum = 7:5u Std. Dev./Mean = 11%u Fit to Normal Distribution = .940u Regression Coefficient (r) = .35u P(N,r) = .35u Range in DUT response was small. Conclusions
about the fit to a Normal Distribution and correlationto exposure were is limited by the small samplesize.
Variation in Upset Rates per DUT in the CRUX Electronics BoxDUTs Ordered by Increasing Exposure to the Environment
b4c3
b4c4
b4c1b4c11
b4c7 b4c0
b4c2
b4c5
b4c6
-100
-80
-60
-40
-20
0
20
40
60
80
100
Per
cent
Diff
eren
ce fr
om th
e A
vera
ge
b=board #c=chip #
Distribution of DUT Upset Sensitivity
Total Number of Upsets on DUT
Num
ber o
f DU
Ts in
Ran
ge
0
1
2
3
6000 6500 7000 7500 8000 8500 9000 9500
ExpectedNormal
Work supported by USAF/Space Division, DSWA & NASA/HQ
HITACHI/ELMO 1M - 16 DUTs
5 6 7 8 9 10
Average Daily > 50 MeV Proton Fluence x 108
4200
4400
4600
4800
5000
5200
5400
5600
5800
6000
6200
6400
6600
Tota
l Num
ber o
f Ups
ets
Linear Regression Fit - # of Upsets vs Device Exposure
u Total # of Upsets = 83,049u Mean = 5191, Maximum:Minimum = 7:5u Std. Dev./Mean = 9%u Fit to Normal Distribution = .964u Regression Coefficient (r) = .35u Probability (N,r) = .18u Parameters indicate small DUT to DUT variation &
moderate correlation of upset rate to DUTexposure.
Variation in Upset Rates per DUT in the CRUX Electronics BoxDUTs Ordered by Increasing Exposure to the Environment
b2c10 b2c9
b2c3 b2c8
b2c14
b2c4b2c1
b2c12b2c7
b2c15
b2c13 b2c11
b2c2
b2c6b2c0 b2c5
-100
-80
-60
-40
-20
0
20
40
60
80
100
Per
cent
Diff
eren
ce fr
om th
e A
vera
ge
b=board #c=chip #
Distribution of DUT Upset Sensitivity
Total Number of Upsets on DUT
Num
ber o
f DU
Ts in
Ran
ge
0
1
2
3
4
5
6
7
8
4000 4500 5000 5500 6000 6500
ExpectedNormal
Work supported by USAF/Space Division, DSWA & NASA/HQ
MICRON 256K - 40 DUTs
5 6 7 8 9 10
Average Daily > 50 MeV Proton Fluence x 108
6000
7000
8000
9000
10000
11000
12000
13000
Tota
l Num
ber o
f Ups
ets
Linear Regression Fit - # of Upsets vs Device Exposure
u Total # of Upsets = 370,632u Mean = 9265, Maximum:Minimum = 9:5u Std. Dev./Mean = 12%u Fit to Normal Distribution = .981u Regression Coefficient (r) = .61u Probability (N,r) < .001u Parameters indicate small DUT to DUT variation,
good fit to normal distribution, and strongcorrelation of upset rate to DUT exposure.
Variation in Upset Rates per DUT in the CRUX Electronics BoxDUTs Ordered by Increasing Exposure to the Environment
b8c1
0b8
c8b5
c12
b6c1
4b5
c13
b1c9
b7c2
b5c7
b5c1
4b6
c15
b1c4
b8c1
b6c1
2b6
c6b5
c11
b1c8
b1c1
5b6
c13
b7c3 b1
c10
b1c1
1b8
c4b6
c7b1
c1b6
c11
b1c1
3b1
c3b1
c14
b5c1
5b1
c2 b6c5
b8c0
b1c0
b1c1
2b5
c6 b5c5 b1
c7b1
c6b1
c5
b8c9
-100
-80
-60
-40
-20
0
20
40
60
80
100
Per
cent
Diff
eren
ce fr
om th
e A
vera
ge
b=board #c=chip #
Distribution of DUT Upset Sensitivity
Total Number of Upsets on DUT
Num
ber o
f DU
Ts in
Ran
ge
0
2
4
6
8
10
12
14
16
18
6000 7000 8000 9000 10000 11000 12000 13000
ExpectedNormal
Work supported by USAF/Space Division, DSWA & NASA/HQ
EDI 256K - 18 DUTs
5 6 7 8 9 10
Average Daily > 50 MeV Proton Fluence x 108
0
200
400
600
800
1000
1200
1400
1600
1800
2000
Tota
l Num
ber o
f Ups
ets
Linear Regression Fit - # of Upsets vs Deice Exposure
u Total # of Upsets = 11,065u Mean = 615, Maximum:Minimum = 9:1u Std. Dev./Mean = 81%u Fit to Normal Distribution = .772u Regression Coefficient (r) = .-.39u Probability (N,r) = .107u Parameters indicate large DUT to DUT variation,
trimodal distribution, and poor correlation of upset rate toexposure.
u EDI uses parts from different foundries, therefore, widevariation in DUT response is expected.
Variation in Upset Rates per DUT in the CRUX Electronics BoxDUTs Ordered by Increasing Exposure to the Environment
b6c10
b5c3b6c1
b6c4
b7c15
b8c3
b7c7
b7c12
b7c13
b7c11
b7c14 b5c2b8c2
b7c6b6c0
b7c5
b6c8b6c9
-80
-60
-40
-20
0
20
40
60
80
100
Per
cent
Diff
eren
ce fr
om th
e A
vera
ge
b=board #c=chip #
Distribution of DUT Upset Sensitivity
Total Number of Upsets on DUT
Num
ber o
f DU
Ts in
Ran
ge
0
1
2
3
4
5
6
7
8
0 200 400 600 800 1000 1200 1400 1600 1800 2000
ExpectedNormal
Work supported by USAF/Space Division, DSWA & NASA/HQ
IDT 256K - 19 DUTs
5 6 7 8 9 10
Average Daily > 50 MeV Proton Fluence
3400
3600
3800
4000
4200
4400
4600
4800
5000
5200
5400
Tota
l Num
ber o
f Ups
ets
Linear Regression Fit - # of Upsets vs Device Exposure
Variation in Upset Rates per DUT in the CRUX Electronics BoxDUTs Ordered by Increasing Exposure to the Environment
b7c10b7c8 b7c9
b7c4b6c2
b6c3 b5c4
b8c12 b5c1 b8c11 b7c1
b8c14b7c0
b8c6 b8c15
b8c13
b8c7 b5c0
b8c5
-100
-80
-60
-40
-20
0
20
40
60
80
100
Per
cent
Diff
eren
ce fr
om th
e A
vera
geu Total # of Upsets = 79,513u Mean = 4185, Maximum:Minimum = 3:2u Std. Dev./Mean = 12%u Fit to Normal Distribution = .937u Regression Coefficient (r) = .67u Probability (N,r) < .001u Parameters indicate small DUT to DUT variation
and excellent correlation of upset rate to exposure. b=board #c=chip #
Distribution of DUT Upset Sensitivity
Total Number of Upsets on DUT
Num
ber o
f DU
Ts in
Ran
ge
0
1
2
3
4
5
3400 3600 3800 4000 4200 4400 4600 4800 5000 5200 5400
ExpectedNormal
Work supported by USAF/Space Division, DSWA & NASA/HQ
Sensitivity to Programmed Logic State
u CRUX flight data verify laboratory tests showing that many SRAMs havedifferences in upset sensitivity depending on their programmed logic state.
u DUTs were reprogrammed to opposite logic state about every 21 hours.u Some DUTs were programmed to a checkerboard pattern.
Part Type % of 1s to 0sUpsets
% of 0s to 1sUpsets
MICRON 1M 98 2
EDI 1M 54 46
HITACHI/ELMO 1M 72 28
MICRON 256K 80 20
EDI 256K 68 32
IDT 256K 82 18
SRAM Sensitivity to Programmed Logic State
Work supported by USAF/Space Division, DSWA & NASA/HQ
Multiple Bit Upsets & Stuck Bit Errorsu Multiple Bit Upsets (MBUs) were observed on all part types.
» HITACHI/ELMO 1M DUTs showed highest incidence of MBUs.» For MICRON 256K, heavy ions were more likely to induce MBUs than SEUs (43% vs 3% of
total).» MBUs increased toward the end the mission.
u Stuck Bit Errors were observed on all part types.» Highest incidence was on EDI 1M and IDT 256K parts.» For IDT 256K, heavy ions were more likely to induce stuck bits than SEUs (50% vs 3% of
total).» Stuck bits on 20 DUTs coincided with with an October 1995 solar event (Mission Day 444).
Part Type MBUs/bit-20 months Stuck Bits/bit-20 months
MICRON 1M 1.2 x 10-7 1.7 x 10 –7
EDI 1M 2.1 x 10 –7 6.1 x 10-6
HITACHI/ELMO 1M 8.9 x 10-6 1.8 x 10-7
MICRON 256K 2.6 x 10-6 1.0 x 10-6
EDI 256K 1.7 x 10-6 6.4 x 10-7
IDT 256K 8.0 x 10-7 6.2 x 10-6
MBU & Stuck Bit Rates on CRUX SRAMs
Work supported by USAF/Space Division, DSWA & NASA/HQ
Multiple Bit UpsetsMultiple Bit Upsets on CRUX SRAMs vs Dipole Shell Parameter
1
10
100
0 100 200 300 400 500 600 700
Number of Days from Launch
Dip
ole
She
ll P
aram
eter
- L
MICRON 1MEDI 1MHITACHI/ELMO 1MMICRON 256KEDI 256KIDT 256KL = 3Solar Event
Work supported by USAF/Space Division, DSWA & NASA/HQ
Stuck Bit ErrorsStuck Bit Errors vs Dipole Shell Parameter
1
10
100
0 100 200 300 400 500 600 700
Number of Days from Launch
Dip
ole
She
ll P
aram
eter
- L
MICRON 1MEDI 1MHITACHI/ELMO 1MMICRON 256KEDI 256KIDT 256KL = 3Solar Event
Work supported by USAF/Space Division, DSWA & NASA/HQ
Upset Rates per Device Type
u Upset rates calculated for the entire 20 month mission were 2X higher thanthose calculated for the first 262 days.
u Environment exposure increased during the CRUX mission due to twofactors:
» Orbit precession into more intense Van Allen belt regions resulted in a 30%increase in high energy proton fluence.
» Proton and heavier ion levels increased by an estimated 40% from 1994 to 1996due to solar cycle variations, i.e., levels increase as solar cycle goes into solarminimum.
u Device Degradation Due to Dose?» Dose on DUTs is estimated to be within 7 krads to 10 krads depending on the
location in box.v CRUX dosimeters measured the dose for only the first 90 days of the mission due to
power cutoff during a spacecraft safehold.v Dosimeter data were extrapolated to cover the entire mission.
» Upset rates increased by the same factor of 2 on all part types.
u Conclusion: Upset rate increase was most likely due to increases in theenvironment, and not to SEU/total dose synergism.
Work supported by USAF/Space Division, DSWA & NASA/HQ
Upset Rates per Part Type
Daily Upset Rates per Part TypeAPEX: I=70 deg, H=362/2544 km, Entire Mission
0.0E+00
1.0E-04
2.0E-04
3.0E-04
4.0E-04
5.0E-04
1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3
Dipole Shell Parameter - L
Ups
et R
ate
(#/(b
it-da
y)
MICRON 256KIDT 256KEDI 1MMICRON 1MHITACHI 1MEDI 256K
Work supported by USAF/Space Division, DSWA & NASA/HQ
V D-S L-Shell Lon.(deg)
Lat.(deg)
Alt.(km)
178 4.4 -93 -69 2,518154 5.8 -7 62 1.983130 3.6 10 58 1.228130 7.0 -74 55 1,285148 5.9 -141 -69 1,040172 17.1 -41 68 2,527196 6.4 133 70 2,487
V D-S L-Shell Lon.(deg)
Lat.(deg)
Alt.(km)
68 3.4 66 61 43183 8.5 -177 -63 2,51368 9.6 -48 61 2,52089 1.3 161 15 2,26755 8.9 -164 70 2,05780 8.7 -172 -67 1,02080 1.4 -123 -4 2,288
SEBs on 100 Volt DUTs
SEBs on 200 Volt DUTs at L > 3
SEBs on Power MOSFETs
- 1 8 0 - 1 2 0 - 6 0 0 6 0 1 2 0 1 8 0
L o n g i t ude
- 9 0
- 6 0
- 3 0
0
3 0
6 0
9 0
Latit
ude
1000
1000
10000
2 0 0 V o lt B o a r d S E B s1 5 0 0 - 1 9 9 9 k m
P r o t o n F l u x C o n t o u r s f o r E n e r g y > 5 0 M e V ( A P 8 - M I N )
L = 3
L = 3
160 166 172 178 184 190 196
Voltage Drain-to-Source (Volts)
0
25
50
75
100
125
150
175
200
Num
ber o
f SE
Bs
SEBs As Function of Voltage Drain-to-Source For L < 3(August 11, 1994 to May 17, 1996)
Results For 200 Volt Boards
Work supported by USAF/Space Division, DSWA & NASA/HQ
Summaryu SRAMs
» SEU rates on these commercial SRAMs are strongly dependent on proton fluence levels.» Large differences in the distribution of the # of SEUs on individual DUTs were observed
between part types.» Not all differences in the # of SEUs on DUTs can be attributed due to exposure differences.
Device to device variation within a flight lot also plays a major role.» The variation of DUT SEU performance within the box enclosure on the HITACHI/ELMO 1M,
IDT 256K, and EDI 1M DUTs were within ~20% of the average. For the MICRON 256K, thespread was within ~30% of the average. The MICRON 1M and EDI 256K DUTs had verybroad distributions in device performance, indicating that DUTs may not have come from thesame run lot.
» SEU and MBU rates increased with mission time corresponding to the solar cycle increase inproton and heavier ion levels .
» A small solar event in October 1995 may have caused stuck bit errors on 10 DUTs. The stuckbit errors occurred at altitude 495 km, but outside of the SAA.
u Power MOSFETs» SEBs on the 100 volt Power MOSFETs did not occur below 55 V D-S .» SEBs on the 200 volt Power MOSFETs did not occur below 130 V D-S. The voltage threshold
was higher for trapped proton induced SEBs than for heavy ion induced SEBs.» The SEB rate is strongly dependent on voltage threshold.
Work supported by USAF/Space Division, DSWA & NASA/HQ
References & Acknowledgements
[1] C.S. Dyer, C.J. Watson, C.L. Peerless, A.J. Sims, and J.L. Barth, “Measurements of theRadiation Environment from CREDO-II on STRV and APEX,” IEEE Trans. on NS, Vol.43, No. 6, December 1996.
[2] J.W. Adolphsen, J.L. Barth, E. G. Stassinopoulos, T. Gruner, M. Wennersten, K.A.LaBel, C. M. Seidleck, “Single Event Upset Rates on 1 Mbit and 256 Kbit Memories:CRUX Experiment on APEX,” IEEE Trans. on N.S., Vol. 42, No. 6, December 1995.
[3] J.W. Adolphsen, J.L. Barth, E. G. Stassinopoulos, T. Gruner, M. Wennersten, K.A.LaBel, C. M. Seidleck, “SEE Data from the APEX Cosmic Ray Upset Experiment:Predicting the Performance of Commercial Devices in Space,” IEEE Trans. on N.S.,Vol. 43, No. 3, June 1996.
[4] J. W. Adolphsen, J.L. Barth, and G.B. Gee, “First Observation of Proton Induced PowerMOSFET Burnout on Space: The CRUX Experiment on APEX,” IEEE Trans. on N.S.,Vol. 43, No. 6, December 1996.
[5] D. Oberg, J. L. Wert, E, Normand, P. P. Majewski, and S. A. Wender, “First Obsevationof Power MOSFET Burnout with High Energy Neutrons,” IEEE Trans. On N.S., Vol. 43,No. 6, December 1996.
We are indebted to the US Air Force/Space Division for the flight opportunity on the APEXmission. NASA/HQ and Defense Special Weapons Agency supported the data analysis.