ASTM F1262M-95
(Guide)Standard Guide for Transient Radiation Upset Threshold of Digital Integrated Circuits
Standard Guide for Transient Radiation Upset Threshold of Digital Integrated Circuits
SCOPE
1.1 This guide is to assist experimenters in measuring the transient radiation upset threshold of silicon digital integrated circuits exposed to pulses of ionizing radiation greater than 103 Gy (Si)/s.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: F 1262M – 95
METRIC
Standard Guide for
Transient Radiation Upset Threshold Testing of Digital
Integrated Circuits [Metric]
This standard is issued under the fixed designation F 1262M; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope for small time delays caused by the propagation delay of
internal logic elements).
1.1 This guide is to assist experimenters in measuring the
3.1.1.1 Discussion—Combinational circuits contain no in-
transient radiation upset threshold of silicon digital integrated
ternal storage elements. Hence, the output signals are not a
circuits exposed to pulses of ionizing radiation greater than 10
function of any signals that occurred at past times. Examples of
Gy (Si)/s.
combinational circuits include gates, adders, multiplexers and
1.2 This standard does not purport to address all of the
decoders.
safety concerns, if any, associated with its use. It is the
3.1.2 complex circuit response mechanisms—For medium
responsibility of the user of this standard to establish appro-
scale integration (MSI) and higher devices it is useful to define
priate safety and health practices and determine the applica-
three different categories of devices in terms of their internal
bility of regulatory limitations prior to use.
design and radiation response mechanisms.
2. Referenced Documents 3.1.3 over-stressed device—A device that has conducted
more than the manufacturer’s specified maximum current, or
2.1 ASTM Standards:
dissipated more than the manufacturer’s specified maximum
E 666 Practice for Calculating Absorbed Dose from Gamma
power.
or X Radiation
3.1.3.1 Discussion—In this case the DUT is considered to
E 668 Practice for the Application of Thermoluminescence-
be overstressed even if it still meets all of the manufacturer’s
Dosimetry (TLD) systems for Determining Absorbed Dose
specifications. Because of the overstress, the device should be
in Radiation-Hardness Testing of Electronic Devices
evaluated before using it in any high reliability application.
F 867M Guide for Ionizing Radiation Effects (Total Dose)
3.1.4 sequential logic—A digital logic system with the
Testing of Semiconductor Devices [Metric]
property that its output state at a given time depends on the
2.2 Military Standards:
sequence and time relationship of logic signals that were
Method 1019 in MIL-STD-883. Steady-State Total Dose
previously applied to its inputs.
Irradiation Procedure
3.1.4.1 Discussion—Examples of sequential logic circuits
Method 1021 in MIL-STD-883. Dose Rate Threshold for
include flip-flops, shift registers, counters, and arithmetic logic
Upset of Digital Microcircuits.
units.
3. Terminology
3.1.5 state vector—A state vector completely specifies the
logic condition of all elements within a logic circuit.
3.1 Definitions:
3.1.5.1 Discussion—For combinational circuits, the state
3.1.1 combinational logic—A digital logic system with the
vector includes the logic signals that are applied to all inputs:
property that its output state at a given time is solely deter-
for sequential circuits, the state vector must also include the
mined by the logic signals at its inputs at the same time (except
sequence and time relationship of all input signals. In this
guide the output states will also be considered part of the state
This guide is under the jurisdiction of ASTM Committee F-1 on Electronics and
vector definition. For example, an elementary 4-input NAND
is the direct responsibility of Subcommittee F01.11 on Quality and Hardness
gate has 16 possible state vectors, 15 of which result in the
Assurance.
same output condition (“1” state). A 4-bit counter has 16
Current edition approved Nov. 10, 1995. Published January 1996.
Annual Book of ASTM Standards, Vol 12.02. possible output conditions, but many more state vectors be-
Annual Book of ASTM Standards, Vol 10.04.
cause of its dependence on the dynamic relationship of various
Available from Standardization Documents Order Desk, Bldg. 4, Section D,
input signals.
700 Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
F 1262M – 95
3.1.6 upset response—The electrical response of a circuit (10) Recommended radiation level at which to begin the test
when it is exposed to a pulse of transient ionizing radiation. sequence, and
3.1.6.1 Discussion—Two types of upset response can occur: (11) Procedure to adjust the dose rate during testing.
(12) Device temperature during test.
(1) transient output error, for which the instantaneous output
4.3 The state vectors in which the device is to be irradiated
voltage of an operating digital circuit is greater than a predetermined
are determined from the basic (see 8.2.1) and topological
value (for a low output condition) or less than a predetermined value
(for a high output condition), and the circuit spontaneously recovers to analysis, (see 8.2.2) or both.
its pre-irradiation condition after the radiation pulse subsides. The
predetermined values mentioned above are agreed to by all parties
5. Significance and Use
participating in the test and should be included in the test plan.
5.1 Digital logic circuits are used in system applications
(2) stored logic state error, for which there is a change in the state
where they are exposed to pulses of radiation. It is important to
of one or more internal logic elements that does not recover spontane-
know the minimum radiation level at which transient failures
ously after the radiation pulse. Because the radiation changes the state
vector, the circuit spontaneously recovers to a different logic state. This
can be induced, since this affects system operation.
does not imply the change will always be immediately observable on a
circuit output. However, the circuit can be restored to its original state
6. Interferences
vector by re-initializing it afterwards.
6.1 Accumulated Ionizing Dose—Many devices may be
3.1.6.2 Discussion—Although the term upset response is
permanently damaged by the accumulated ionizing dose they
usually used to describe output voltage responses, some
are exposed to during upset testing. This limits the number of
devices, such as open collector gates, are better characterized
radiation pulses that can be applied during transient upset
by measuring the output current. Upset response also includes
testing. Accumulated ionizing dose sensitivity depends on
the transient currents that are induced in the power supply leads
fabrication techniques and device technology. Metal oxide
(sometimes very large) as well as the response of the device
semiconductor (MOS) devices are especially sensitive to
inputs, although in most applications the input response is not
accumulated ionizing dose damage. Newer bipolar devices
significant.
with oxide-isolated sidewalls may also be affected by low
levels of accumulated ionizing dose. The maximum ionizing
4. Summary of Guide
dose to which devices are exposed must not exceed 10 % (see
4.1 For transient radiation upset threshold tests, the transient 8.4.5) of the typical ionizing dose failure level of the specific
output voltage and the condition of internal storage elements, part type.
or both, is measured at a succession of radiation levels to 6.2 Dosimetry Accuracy—Since this guide ultimately deter-
determine the radiation level for which transient voltage or
mines the dose rate at which upset occurs, dosimetry accuracy
functional test errors first occur. An oscilloscope, digital inherently limits the accuracy of the guide.
storage oscilloscope, transient digitizer or similar instrument is
6.3 Latchup—Some types of integrated circuits may be
used to measure the output transient voltage. Functional tests driven into a latchup condition by transient radiation. If latchup
are made immediately after irradiation to detect internal
occurs, the device will not function properly until power is
changes in state induced by the radiation. The device is initially temporarily removed and reapplied. Permanent damage may
biased and set up in a predetermined condition. The test
also occur. Although latchup is an important transient response
conditions are determined from topological analyses or by mechanism, this procedure is not applicable to latchup testing.
testing the device in all possible logic state combinations.
Functional testing after irradiation is required to detect internal
4.2 A number of factors are not defined in this guide and changes of state, and this will also detect latchup.
must be agreed upon beforehand by the parties to the test.
6.4 Package Response—At dose rates above 10 Gy (Si)/s
These factors are described in the test plan. As a minimum the
the response may be dominated by the package response rather
test plan must specify the following:
than the response of the integrated circuit device being tested.
(1) Pulse width, energy spectrum, and type of radiation
For high speed devices, this may include lead/bondwire effects
source,
with upsets caused solely by the radiation pulse’s rise and fall
(2) Voltage and electrical loading conditions on each pin of rates rather than dose rate. Package effects can be minimized
the device during testing,
by adequately decoupling the power supply with appropriate
(3) Resolution and accuracy required for the upset response high-speed capacitors.
threshold of individual devices, along with the method used to
6.5 Steps Between Radiation Levels—The size of the steps
vary the radiation level,
between successive radiation levels limits the accuracy with
(4) Failure criterion for transient voltage upset, output
which the dose rate upset threshold is determined. Cost
current, and power supply current as applicable,
considerations and ionizing dose damage limit the number of
(5) Measuring and reporting I , transient output voltage radiation levels that can be used to test a given device.
pp
and transient output current levels,
6.6 Limited Number of State Vectors—Cost, testing time,
(6) Functional test to be made after irradiation, and cumulative ionizing radiation usually make it necessary to
(7) Power supply and operating frequency requirements,
restrict upset testing to a small number of state vectors. These
(8) State vectors used for testing, state vectors must include the most sensitive conditions in
(9) Radiation levels to use for transient response measure- order to avoid misleading results. An analysis is required to
ments, select the state vectors used for radiation testing to make sure
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
F 1262M – 95
that circuit and geometrical factors that affect the upset required. The line drivers must be designed so that their own
response are taken into account. response to transient ionizing radiation is much smaller than
that of the circuit being measured (see Note 4).
7. Apparatus
NOTE 4—Although line drivers are normally not placed in the direct
7.1 The equipment and information required for this guide
radiation beam, there is always some stray radiation that may affect the
includes an electrical schematic of the test circuit, a logic
line driver. Furthermore, replacement currents in the wiring that connects
diagram of the device to be tested, a transient radiation
the line driver to the circuit under test may also introduce a spurious
simulation source, dosimetry equipment, and electrical equip-
response.
ment for the measurement of the device response and func-
7.3.3 General Purpose Test Equipment—Power supplies,
tional testing. If the alternate topological analysis approach is
pulse generators, cables and termination resistors that are
to be used, (see 8.2.2) then a photomicrograph or composite
required to bias the device and establish its internal operating
mask drawing of the device is also needed.
conditions are needed.
7.2 Radiation Simulation and Dosimetry Apparatus:
7.3.4 Transient Response Measuring Device—An oscillo-
7.2.1 Transient Radiation Source—A pulsed high energy
scope, transient digitizer or similar device shall be used to
electron or bremsstrahlung source that can provide a dose rate
measure the transient response of the device under test. The
in excess of the upset response threshold level of the device
bandwidth and sensitivity of this equipment must be compat-
being tested at the pulse width specified in the test plan is
ible with the pulse width and measurement criteria in the test
needed. A linear accelerator (LINAC) with electron energies of
plan.
10 to 25 MeV is preferred (see Note 1), although in some
7.3.5 Functional Test System—A system that is set up to test
instances a flash X ray with end point energy above 2.0 MeV
the functional operation of the device under test while it is in
may be utilized (see Note 2 and Note 3). It is usually much
the radiation test fixture is required. This may consist of (1)
more difficult to synchronize a flash X-ray pulse with circuit
general purpose equipment such as pulse generators,
operation, which limits the applicability of a flash X ray.
oscilloscopes/transient digitizers, or logic analyzers, (2)a
NOTE 1—Linac radiation pulses are made from a train of discrete
commercial integrated circuit test system, or (3) a custom test
“micropulses” occurring at the linac radio frequency (RF). This high
circuit/fixture. The specific requirements of the functional test
frequency pulse structure could cause erroneous results for high frequency
system depend on the specifications and requirements of the
devices under test such as gallium arsenide. This has not yet been directly
device under test and are included in the test plan.
observed.
7.3.6 Temperature Measuring Equipment—A thermometer,
NOTE 2—The absorption coefficient of photons in silicon and packag-
ing materials is relatively flat at energies above 2 MeV, and has a nearly calorimeter, or other temperature measuring device that can
constant ratio to the absorption coefficient of typical dosimetry systems.
measure the ambient temperature with an accuracy of at least6
At lower energies absorption coefficients increase, which can introduce
3°C.
large dosimetry errors if the end point energy in a bremsstrahlung sour
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.