Samsung Rev C Report 7-03

Single Event Effects Qualification
UT8Q512K8 (RQ02)
Lot 6ZVL04 4Mbit SRAM
7/21/03
Craig Hafer
719-594-8319
[email protected]
SUMMARY--Single event effects qualification testing was performed on the UTMC 4Mbit
SRAM, (Samsung Rev C die), Lot 6ZVL04, at the Lawrence Berkeley Laboratory using
heavy ion beams from their 88-inch Cyclotron. The SRAM was shown to be immune to
single event latchup (SEL) from ions with a linear energy transfer (LET) of >84 MeV-cm2/mg
when tested at 125°C and 3.6V Vdd (considered worst-case conditions for SEL). SEL was
observed at an LET of 100 MeV-cm2/mg, so the LET threshold for SEL lies between 84-100
MeV-cm2/mg. The SRAM was also qualified for single event upset (SEU) at 25°C and 3.0V
(considered worst-case conditions for SEU). The error-rate calculated using the Adams
90% worst-case geosynchronous environment (100 mils of Al shielding) [1] is
approximately 1.14E-8 errors/bit-day.
Introduction
This report describes single event effects (SEE) test data collected on the Aeroflex UTMC 4Mbit
SRAM, Lot 6ZVL04. The SEE testing consisted of monitoring for two SEE effects, single event
latchup (SEL) and single event upset (SEU). It was performed with the Lawrence Berkeley
National Laboratory (LBNL) 88-inch cyclotron and the Aerospace heavy ion test chamber. The
SEU data was collected on April 4, 2003 and the SEL data on May 3, 2003.
Experimental Conditions
Single event upset and single event latch-up characterizations were performed on the 4Mbit
SRAM, Lot 6ZVL04, at the Lawrence Berkley Laboratory using their 88-inch Cyclotron facility.
Both SEU and SEL were tested under worst-case temperature and voltage conditions. In
accordance with EIA/JESD57, the device was tested for SEL at 125C and 3.6V and was tested
for SEU at 25C and 3.0V. The devices were exposed to the ion beam in vacuum and were
delidded and tested prior to insertion into the SEE test chamber.
In order to fully evaluate SEU, a broad range of LET values are required. To achieve this, a
variety of different ions were selected from LBNL’s 4.5-MeV/amu “nucleon cocktail” [2] and used
at angles from a normal incidence to a maximum of 60° (the effective LET is equal to the LET at
normal incidence multiplied by the secant of the angle of incidence). The ions and their LETs at
normal incidence are shown in Table 1. The maximum effective LET for this test was
approximately 126 MeV-cm2/mg.
July 21, 2003
Table 1 LBNL Cyclotron 4.5MeV/AMU cocktail ions, and their LETs
Ion
Energy
(MeV)
LET
(MeV·cm2/mg)
Boron
Nitrogen
Neon
Argon
Cobalt
Copper
Krypton
Xenon
45
67
90
180
266
293
378
603
1.2
3.2
5.6
15
25.8
30
38
64
During the SEL testing, all four-qualification units were placed in the test chamber on the same
test board. The parts were biased statically and the current monitored during the duration of the
2
test. Each component was exposed to a minimum effective fluence of 1.4E6 ions/cm .
Results
To verify the SEL hardness of the UTMC SRAM, xenon was chosen from LBL’s “nucleon cocktail”
and used at an oblique angle of incidence (the effective LET is equal to the LET at normal
incidence multiplied by the secant of the angle of incidence). Two samples were first tested at an
angle of 50° (effective LET of 99.6 MeV-cm2/mg) and latchup events were recorded. The angle
of incidence was decreased to 40° (effective LET of 83.5 MeV-cm2/mg) and no latchup events
were measured in all of the four samples that were exposed at this angle of incidence.
The parts were tested under worst-case temperature (+125°C) and supply voltage (3.6V) for
inducing SEL. The devices were exposed to the ion beam in vacuum and were biased using a
typical static SRAM configuration. Four devices were tested. Table 2 summarizes the results of
the tests. As seen in Table 2, no single event induced latch-ups were measured in the four
devices when exposed to Xe ions with a LET of 83.5 MeV-cm2/mg at fluences which exceeded
1.4 x 106 ions/cm2. However, two of the samples were tested at a larger angle of incidence,
resulting in a LET of 99.6 MeV-cm2/mg, and in both cases a latchup was induced. Thus the LET
threshold for single event latchup lies between 83.5-99.6 MeV-cm2/mg. Further, it can be stated
that the device is immune from latchup for LET of < 83.5 MeV-cm2/mg.
Table 2 Single event latch-up results for Lot 6ZVL04 SRAM samples
S/N
Dev.
Temp
(°C)
Ion
Angle, °
LET
(eff.)
Fluence
(eff.)
DVM
(V)
Latch-up
1
2
1
2
3
4
SRAM
SRAM
SRAM
SRAM
SRAM
SRAM
125
125
125
125
125
125
Xe
Xe
Xe
Xe
Xe
Xe
50
50
40
40
40
40
100
100
84
84
84
84
5.7E+4
3.2E+5
1.4E6
1.3E7
1.8E6
1.4E6
3.6
3.6
3.6
3.6
3.6
3.6
1
1
0
0
0
0
July 21, 2003
The single event upset (SEU) response data is shown in Figure 1. This figure is a plot of SEU
error cross-section as a function of LET for the 4 samples, and also includes a fit with a Weibull
distribution (shown with a dashed line). As seen in Fig. 1, the SRAM exhibited upsets from very
low values of LET up to the highest value. The saturated SEU cross section is approximately
7.83E-9 cm²/bit and is included in Table 3 which contains all of the Weibull fit parameters. The
actual SEU cross section data that is plotted in Fig. 1 is tabulated in Table 4. An analysis of the
data using SpaceRadiation 4.0 [3] yields an error rate of 1.14E-8 errors/bit-day in the Adams 90%
worst-case geosynchronous environment with 100 mils of aluminum shielding. The SEU linear
energy transfer (LET) threshold based on one-quarter of the saturated cross-section (LETth(0.25))
for the SRAM is 11.4 MeV-cm2/mg with a saturated cross-section of 7.83E-9 cm2/bit.
Figure 1 SEU Cross Section of Lot 6ZVL04 SRAM Data as a function of LET
Cross Section (cm²/ bit)
1E-7
1E-8
1E-9
Weibull Fit
S/N 1
S/N 2
S/N 3
S/N 4
1E-10
1E-11
0
20
40
60
80
LET (MeV cm²/ mg)
Table 3. Weibull Fit Data and Associated Values
July 21, 2003
Parameter Description
Value
Saturated cross-section
Onset LET
Width
Shape
LETth (0.25)
Device depth
Funnel depth
Adams 90% GEO error rate
7.83E-9 cm /bit
1.43 MeV-cm2/mg
18.18
2.07
11.4 MeV-cm2/mg
0.25µm
0.25µm
1.14E-8 Errors/bit-day
2
100
120
Summary/Conclusions
Single event effects (SEE) qualification testing was performed on the UTMC 4Mbit SRAM, Lot
6ZVL04 at the Lawrence Berkeley National Laboratory using heavy ion beams from their 88-inch
Cyclotron. The Lot 6ZVL04 SRAM was shown to be prone to SEL at very high values of linear
energy transfer, LET, having a LET threshold for SEL within the range of 83.5-99.6 MeV-cm2/mg.
Further, the SRAM was shown to be immune to SEL for LET values of up to 83.5 MeV-cm2/mg
when tested at 125°C and 3.6V Vdd (worst-case conditions for SEL). The Lot 6ZVL04 SRAM
was also qualified for SEU at 25°C and 3.0V (worst-case conditions for SEU). The SEU error-rate
for an Adams 90% worst-case geosynchronous environment (100 mil Al shielding) is
approximately 1.14E-8 errors/bit-day.
Table 4 Tabulation of SEU Cross Section Data in Lot 6ZVL04 SRAM Samples
Part #
Ion
Nom.
LET
Angle, °
Errors
Fluence
Eff.
Fluence
Eff.
LET
X-Sec,
cm²/bit
DVM
(V)
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
Xe
Xe
Xe
Kr
Ar
Ne
Ne
N
Xe
Xe
Xe
Kr
Ar
Ar
Ar
Ne
N
Xe
Xe
Kr
Ar
Ne
N
Xe
Xe
Kr
Ar
Ar
Ne
Ne
Ne
N
Xe
63
63
63
38
15
5.6
5.6
3.2
63
63
63
38
15
15
15
5.6
3.2
63
63
38
15
5.6
3.2
63
63
38
15
15
5.6
5.6
5.6
3.2
63
60
45
0
0
0
45
0
0
60
45
0
0
60
45
0
0
0
60
0
0
0
0
0
60
0
0
60
0
60
45
0
0
60
674
228
1107
935
261
277
217
130
489
258
1522
276
338
229
304
378
682
207
228
246
323
348
273
252
227
248
314
331
326
464
342
337
252
4.0E+4
1.0E+4
4.1E+4
1.9E+4
1.3E+4
3.5E+4
1.1E+5
2.4E+5
3.5E+4
1.3E+4
3.6E+4
1.1E+4
3.6E+4
2.0E+4
2.6E+4
3.9E+5
2.7E+6
1.5E+4
7.8E+3
1.2E+4
3.0E+4
3.2E+5
9.3E+5
1.5E+4
6.5E+3
9.9E+3
2.8E+4
3.2E+4
1.1E+5
1.3E+5
3.0E+5
7.4E+5
1.5E+4
2.0E+4
7.3E+3
4.1E+4
1.9E+4
1.3E+4
2.5E+4
1.1E+5
2.4E+5
1.7E+4
8.9E+3
3.6E+4
1.1E+4
1.8E+4
1.4E+4
2.6E+4
3.9E+5
2.7E+6
7.7E+3
7.8E+3
1.2E+4
3.0E+4
3.2E+5
9.3E+5
7.3E+3
6.5E+3
9.9E+3
1.4E+4
3.2E+4
5.3E+4
9.3E+4
3.0E+5
7.4E+5
7.3E+3
126
89
63
38
15
8
6
3
126
89
63
38
30
21
15
6
3
126
63
38
15
6
3
126
63
38
30
15
11
8
6
3
126
8.1E-09
7.5E-09
6.4E-09
1.2E-08
5.0E-09
2.6E-09
4.7E-10
1.3E-10
6.7E-09
6.9E-09
1.0E-08
6.0E-09
4.5E-09
3.9E-09
2.8E-09
2.3E-10
6.1E-11
6.5E-09
7.0E-09
5.0E-09
2.6E-09
2.6E-10
7.0E-11
8.3E-09
8.3E-09
5.9E-09
5.4E-09
2.5E-09
1.5E-09
1.2E-09
2.7E-10
1.1E-10
8.3E-09
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
July 21, 2003
References
1. J.H. Adams, Jr. “The Natural Radiation Environment Inside Spacecraft,” IEEE Trans. Nucl.
Sci., NS-29, pp. 2095-2100 (1982).
2. M. A. McMahan “Cocktails and Other Libations-The 88-Inch Cyclotron Radiation Effects
Facility,” IEEE Radiation Effects Data Workshop, pp.156-163 (1998).
3. Space Radiation Associates, Space Radiation 4.0 Users Manual.
July 21, 2003
Single Event Effects Qualification
UT9Q512K8 (RQ03)
Lot 62C006 4Mbit SRAM
7/21/03
Craig Hafer
719-594-8319
[email protected]
SUMMARY--Single event effects qualification testing was performed on the UTMC Lot 62C006
4Mbit SRAM, (Samsung Rev C die), Lot 62C006, at the Lawrence Berkeley Laboratory using
heavy ion beams from their 88-inch Cyclotron. The SRAM was shown to be immune to single
event latchup (SEL) to a linear energy transfer (LET) of >82 MeV-cm2/mg when tested at 125°C
and 5.5V Vdd (considered worst-case conditions for SEL). The SRAM was also qualified for single
event upset (SEU) at 25°C and 4.5V (considered worst-case conditions for SEU). The error-rate
calculated using the Adams 90% worst-case geosynchronous environment (100 mil of Al
shielding) [1] is approximately 2.69E-8 errors/bit-day.
Introduction
This report describes single event effects (SEE) test data collected on the Aeroflex UTMC 4Mbit
SRAM, Lot 62C006. The SEE testing consisted of monitoring for two SEE effects, single event
latchup (SEL) and single event upset (SEU). It was performed with the Lawrence Berkeley
National Laboratory (LBNL) 88-inch cyclotron and the Aerospace heavy ion test chamber. The
SEL data was collected on July 2, 2002 and the SEU data on April 14, 2003.
Experimental Conditions
Single event upset and single event latch-up characterization were performed on the 4Mbit
SRAM, Lot 62C006 at the Lawrence Berkley Laboratory using their 88-inch Cyclotron facility.
Both SEU and SEL were tested under worst-case temperature and voltage conditions. In
accordance with EIA/JESD57, the device was tested for SEL at 125C and 5.5V and was tested
for SEU at 25C and 4.5V. The devices were exposed to the ion beam in vacuum and were
delidded and tested prior to insertion into the SEE test chamber.
In order to fully evaluate SEU, a broad range of LET values are required. To achieve this a
variety of different ions were selected from LBNL’s 4.5-MeV/amu “nucleon cocktail” [2] and used
at angles from normal incidence to a maximum of 60° (the effective LET is equal to the LET at
normal incidence multiplied by the secant of the angle of incidence). The ions and their LETs at
normal incidence are shown in Table 1. The maximum effective LET for this test was
approximately 126 MeV-cm2/mg.
July 21, 2003
Table 1 LBNL Cyclotron 4.5MeV/AMU cocktail ions, and their LETs
Ion
Energy
(MeV)
LET
(MeV·cm2/mg)
Nitrogen
Neon
Argon
Cobalt
Copper
Krypton
Xenon
Gold
67
90
180
266
293
378
603
887
3.2
5.6
15
25.8
30
38
64
82
During the SEL testing, all four-qualification units were placed in the test chamber on the same
test board. The parts were biased statically and the current monitored during the duration of the
2
test. Each component was exposed to a minimum effective fluence of 1E7 ions/cm .
Results
For qualifying the SEL immunity of the UTMC SRAM, four devices were tested, as discussed
above. Table 2 summarizes the results of the tests. As seen in Table 2, no single event induced
latch-ups were measured when exposed to a total fluence of Au ions which exceeded 1 x 107
ions/cm2.
The single event upset response data is shown in Figure 1. This figure is a plot of SEU error
cross-section as a function of LET for the 4 samples, and also includes a fit with a Weibull
distribution (shown with a dashed line). As seen in Fig. 1, the SRAM exhibited upsets from very
low values of LET up to the highest value. The saturated SEU cross section is approximately
1.5E-8 cm²/bit and is included in Table 3 which contains all of the Weibull fit parameters. The
actual SEU cross section data that is plotted in Fig. 1 is tabulated in Table 4. An analysis of the
data using SpaceRadiation 4.0 [3] yields an error rate of 2.69E-8 errors/bit-day in the Adams 90%
worst-case geosynchronous environment with 100 mils of aluminum shielding. The SEU linear
energy transfer (LET) threshold based on one-quarter of the saturated cross-section (LETth(0.25))
for the SRAM is 9.2 MeV-cm2/mg with a saturated cross-section of 1.49E-8cm2/bit.
Table 2 Single Event latch-up results for Lot 62C006 SRAM samples
S/N
Dev.
Temp
(°C)
Ion
Angle, °
LET
(eff.)
Fluence
(eff.)
DVM
(V)
Latch-up
1
2
3
4
SRAM
SRAM
SRAM
SRAM
125
125
125
125
Au
Au
Au
Au
0
0
0
0
82
82
82
82
1.0E7
1.01E7
1.0E7
1.0E7
5.5
5.5
5.5
5.5
0
0
0
0
Figure 1 SEU Cross Section of Lot 62C006 SRAM Data as a function of LET
July 21, 2003
Cross Section (cm²/ bit)
1E-7
1E-8
1E-9
Weibull Fit
S/N 1
S/N 2
S/N 3
S/N 4
1E-10
1E-11
1E-12
0
20
40
60
80
100
120
LET (MeV cm²/ mg)
Table 3 Weibull Fit Data and Associated Values
Parameter Description
Value
Saturated cross-section
Onset LET
Width
Shape
1.49E-8 cm2/bit
2.02MeV-cm2/mg
11
2.92
9.2 MeV-cm2/mg
0.25 µm
0.25 µm
2.69E-8 Errors/bit-day
LETth (0.25)
Device depth
Funnel depth
Adams 90% GEO error rate
Summary/Conclusions
Single event effects qualification testing was performed on the UTMC Lot 62C006 4Mbit SRAM at
the Lawrence Berkeley National Laboratory using heavy ion beams from their 88-inch Cyclotron.
The SRAM was shown to be immune to SEL for LET values of up to 82 MeV-cm2/mg when tested
at 125°C and 5.5V Vdd (worst-case conditions for SEL). The SRAM was also qualified for SEU at
25°C and 4.5V (worst-case conditions for SEU). The SEU error-rate for a Adams 90% worst-case
geosynchronous environment (100 mil Al shielding) is approximately 2.69E-8 errors/bit-day
Table 4 Tabulation of SEU Cross Section Data in Lot 62C006 SRAM Samples
Part #
July 21, 2003
Ion
Nom.
Angle, °
Errors
Fluence
Eff.
Eff.
X-Sec,
DVM
LET
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
3
4
4
4
4
4
4
4
N
Ne
Kr
Xe
Xe
N
Ne
Ar
Kr
Xe
Xe
N
Ne
Ar
Kr
Xe
Xe
Xe
N
N
Ne
Ne
Ar
Xe
Xe
3.2
5.6
41
63
63
3.2
5.6
15
41
63
63
3.2
5.6
15
41
63
63
63
3.2
3.2
5.6
5.6
15
63
63
0
0
0
0
45
0
0
0
0
0
45
0
0
0
0
0
45
60
0
45
0
45
45
0
45
109
155
122
419
196
91
113
240
128
262
225
67
153
376
704
1899
248
183
101
178
220
457
116
256
128
5.8E+5
9.5E+4
3.5E+3
6.0E+3
3.8E+3
7.2E+5
8.8E+4
5.2E+3
2.4E+3
3.9E+3
5.4E+3
9.7E+5
1.1E+5
7.8E+3
1.8E+4
2.7E+4
6.2E+3
7.9E+3
6.0E+5
1.2E+5
1.0E+5
4.4E+4
4.7E+3
3.1E+3
2.6E+3
Fluence
LET
5.8E+5
9.5E+4
3.5E+3
6.0E+3
2.7E+3
7.2E+5
8.8E+4
5.2E+3
2.4E+3
3.9E+3
3.8E+3
9.7E+5
1.1E+5
7.8E+3
1.8E+4
2.7E+4
4.4E+3
3.9E+3
6.0E+5
8.8E+4
1.0E+5
3.1E+4
3.3E+3
3.1E+3
1.8E+3
3.2
5.6
41.0
63.0
89.1
3.2
5.6
15.0
41.0
63.0
89.1
3.2
5.6
15.0
41.0
63.0
89.1
126.0
3.2
4.5
5.6
7.9
21.2
63.0
89.1
cm²/bit
4.5E-11
3.9E-10
8.3E-09
1.7E-08
1.7E-08
3.0E-11
3.1E-10
1.1E-08
1.3E-08
1.6E-08
1.4E-08
1.6E-11
3.3E-10
1.1E-08
9.3E-09
1.7E-08
1.3E-08
1.1E-08
4.0E-11
4.8E-10
5.2E-10
3.5E-09
8.3E-09
2.0E-08
1.7E-08
(V)
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
4.5
References
4. J. H. Adams, Jr. “The Natural Radiation Environment Inside Spacecraft,” IEEE Trans. Nucl.
Sci., NS-29, pp. 2095-2100 (1982).
5. M. A. McMahan “Cocktails and Other Libations-The 88-Inch Cyclotron Radiation Effects
Facility,” IEEE Radiation Effects Data Workshop, pp.156-163 (1998).
3. Space Radiation Associates, Space Radiation 4.0 Users Manual.
July 21, 2003