1、Designation: F1262M 95 (Reapproved 2008)F1262M 14Standard Guide forTransient Radiation Upset Threshold Testing of DigitalIntegrated Circuits (Metric)1This standard is issued under the fixed designation F1262M; the number immediately following the designation indicates the year oforiginal adoption or
2、, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide is to assist experimenters in measuring the transient radiation upse
3、t threshold of silicon digital integrated circuitsexposed to pulses of ionizing radiation greater than 103 Gy (Si)/s.(matl.)/s.1.1.1 DiscussionThis document is intended to be a guide to determine upset threshold, and is not intended to be a stand-alonedocument.1.2 This standard does not purport to a
4、ddress all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E666 Practice
5、 for Calculating Absorbed Dose From Gamma or X RadiationE668 Practice for Application of Thermoluminescence-Dosimetry (TLD) Systems for Determining Absorbed Dose inRadiation-Hardness Testing of Electronic DevicesF867MF1893 Guide or Ionizing Radiation Effects (Total Dose) Testing for Measurement of I
6、onizing Dose-Rate Survivabilityand Burnout of Semiconductor Devices Metric (Withdrawn 1998)2.2 Military Standards: 3Method 1019 in MIL-STD-883. Steady-State Total Dose Irradiation ProcedureMethod 1021 in MIL-STD-883. Dose Rate Threshold for Upset of Digital Microcircuits.3. Terminology3.1 Definition
7、s:3.1.1 combinational logicA digital logic system with the property that its output state at a given time is solely determined bythe logic signals at its inputs at the same time (except for small time delays caused by the propagation delay of internal logicelements).3.1.1.1 DiscussionCombinational c
8、ircuits contain no internal storage elements. Hence, the output signals are not a function of any signals thatoccurred at past times. Examples of combinational circuits include gates, adders, multiplexers and decoders.3.1.2 complex circuit response mechanismslatchup conditionFor medium scale integra
9、tion (MSI) and higher devices it isuseful to define three different categories of devices in terms of their internal design and radiation response mechanisms.Apersistent anomalous high current state in which a parasitic region (for example, a four layer p-n-p-n or n-p-n-p path) is turnedon by transi
10、ent ionizing radiation.1 This guide is under the jurisdiction of ASTM Committee F01 on Electronics and is the direct responsibility of Subcommittee F01.11 on Nuclear and Space RadiationEffects.Current edition approved June 15, 2008June 1, 2014. Published July 2008 July 2014. Originally approved in 1
11、995. Last previous edition approved in 20022008 asF1262M 95(2002).(2008). DOI: 10.1520/F1262M-95R08.10.1520/F1262M-14.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to
12、 the standards Document Summary page on the ASTM website.3 Available from Standardization Documents Order Desk, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indicat
13、ion of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be cons
14、idered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.3 over-stressed deviceAdevice that has conducted more than the manufacturers specified maximum current, or dissipatedmore than the manufacturers specifie
15、d maximum power.3.1.3.1 DiscussionIn this case the DUT is considered to be overstressed even if it still meets all of the manufacturers specifications. Because of theoverstress, the device should be evaluated before using it in any high reliability application.3.1.4 primary photocurrent (Ipp)a trans
16、ient current flowing from the DUT due to radiation exposure.3.1.4.1 DiscussionThe passage of radiation through the depletion region of a semiconductor device creates electron-hole pairs. These electron-holepairs are then subsequently swept out of the device via the built in potential. This results i
17、n a transient current flowing from theDUT due to radiation exposure.3.1.5 sequential logicA digital logic system with the property that its output state at a given time depends on the sequenceand time relationship of logic signals that were previously applied to its inputs.3.1.5.1 DiscussionExamples
18、 of sequential logic circuits include flip-flops, shift registers, counters, and arithmetic logic units.3.1.6 state vectorA state vector which completely specifies the logic condition of all elements within a logic circuit.3.1.6.1 DiscussionFor combinational circuits, the state vector includes the l
19、ogic signals that are applied to all inputs: for sequential circuits, the statevector must also include the sequence and time relationship of all input signals. In this guide the output states will also beconsidered part of the state vector definition. For example, an elementary 4-input NAND gate ha
20、s 16 possible state vectors, 15 ofwhich result in the same output condition (“1” state).A4-bit counter has 16 possible output conditions, but many more state vectorsbecause of its dependence on the dynamic relationship of various input signals.3.1.7 upset responseThe electrical response of a circuit
21、 when it is exposed to a pulse of transient ionizing radiation.3.1.7.1 DiscussionTwoThree types of upset response can occur:(1) transient output error, for which the instantaneous output voltage of an operating digital circuit is greater than apredetermined value (for a low output condition) or less
22、 than a predetermined value (for a high output condition), and the circuitspontaneously recovers to its pre-irradiation condition after the radiation pulse subsides. The predetermined values mentionedabove are agreed to by all parties participating in the test and should be included in the test plan
23、.(2) stored logic state error, for which there is a change in the state of one or more internal logic elements that does not recoverspontaneously after the radiation pulse. Because the radiation changes the state vector, the circuit spontaneously recovers to adifferent logic state. This does not imp
24、ly the change will always be immediately observable on a circuit output. However, thecircuit can be restored to its original state vector by re-initializing it afterwards.(3) functional interrupt error, a circuit wide state in which the circuit ceases functioning as intended. A soft reset may restor
25、efunctionality to the device. If power cycling is required to restore functionality, the circuit may be in a latched-up state.3.1.7.2 DiscussionAlthough the term upset response is usually used to describe output voltage responses, some devices, such as open collector gates,are better characterized b
26、y measuring the output current. Upset response also includes the transient currents that are induced in thepower supply leads (sometimes very large) as well as the response of the device inputs, although in most applications the inputresponse is not significant.4. Summary of Guide4.1 For transient r
27、adiation upset threshold tests, the transient output voltage and the condition of internal storage elements, orboth, is measured at a succession of radiation levels to determine the radiation level for which transient voltage or functional testerrors first occur. An oscilloscope, digital storage osc
28、illoscope, transient digitizer or similar instrument is used to measure theF1262M 142output transient voltage. Functional tests are made immediately after irradiation to detect internal changes in state induced by theradiation. The device is initially biased and set up in a predetermined condition.
29、The test conditions are determined fromtopological analyses or by testing the device in all possible logic state combinations.4.2 Anumber of factors are not defined in this guide and must be agreed upon beforehand by the parties to the test. These factorsare described in the test plan. As a minimum
30、the test plan must specify the following:(1) Pulse width, energy spectrum, and type of radiation source,(2) Voltage and electrical loading conditions on each pin of the device during testing,(3) Resolution and accuracy required for the upset response threshold of individual devices, along with the m
31、ethod used to varythe radiation level,(4) Failure criterion for transient voltage upset, output current, and power supply current as applicable,(5) Measuring and reporting Ipp, transient output voltage and transient output current levels,(6) Functional test to be made after irradiation,(7) Power sup
32、ply and operating frequency requirements,(8) State vectors used for testing,(9) Radiation levels to use for transient response measurements,(10) Recommended radiation level at which to begin the test sequence, and(11) Procedure to adjust the dose rate during testing.(12) Device temperature during te
33、st.4.3 The state vectors in which the device is to be irradiated are determined from the basic (see 8.2.18.2.2) and topologicalanalysis, (see 8.2.28.2.3) or both.5. Significance and Use5.1 Digital logic circuits are used in system applications where they are exposed to pulses of radiation. It is imp
34、ortant to knowthe minimum radiation level at which transient failures can be induced, since this affects system operation.6. Interferences6.1 Accumulated Ionizing DoseMany devices may be permanently damaged by the accumulated ionizing dose they areexposed to during upset testing. This limits the num
35、ber of radiation pulses that can be applied during transient upset testing.Accumulated ionizing dose sensitivity depends on fabrication techniques and device technology. Metal oxide semiconductor(MOS) devices are especially sensitive to accumulated ionizing dose damage. Newer bipolar devices with ox
36、ide-isolated sidewallsmay also be affected by low levels of accumulated ionizing dose. The maximum ionizing dose to which devices are exposed mustnot exceed 10 % (see 8.4.5) of the typical ionizing dose failure level of the specific part type.6.2 Dosimetry AccuracySince this guide ultimately determi
37、nes the dose rate at which upset occurs, dosimetry accuracyinherently limits the accuracy of the guide.test result.6.3 LatchupSome types of integrated circuits may be driven into a latchup condition by transient radiation. If latchup occurs,the device will not function properly until power is tempor
38、arily removed and reapplied. Permanent damage may also occur.Although latchup is an important transient response mechanism, this procedure is not applicable to latchup testing. Functionaltesting after irradiation but without interrupting power is required to detect internal changes of state, and thi
39、s will also detectlatchup.6.4 Package ResponseAt dose rates above 108 Gy (Si)/s the response may be dominated by the package response rather thanthe response of the integrated circuit device being tested. For high speed devices, this may include lead/bondwire effects withupsets caused solely by the
40、radiation pulses rise and fall rates rather than dose rate. Package effects can be minimized byadequately decoupling the power supply with appropriate high-speed capacitors.6.5 Steps Between Radiation LevelsThe size of the steps between successive radiation levels limits the accuracy with whichthe d
41、ose rate upset threshold is determined. Cost considerations and ionizing dose damage limit the number of radiation levels thatcan be used to test a given device.6.6 Limited Number of State VectorsCost, testing time, and cumulative ionizing radiation usually make it necessary to restrictupset testing
42、 to a small number of state vectors. These state vectors must include the most sensitive conditions in order to avoidmisleading results. An analysis is required to select the state vectors used for radiation testing to make sure that circuit andgeometrical factors that affect the upset response are
43、taken into account.7. Apparatus7.1 The equipment and information required for this guide includes an electrical schematic of the test circuit, a logic diagramof the device to be tested, a transient radiation simulation source, dosimetry equipment, and electrical equipment for themeasurement of the d
44、evice response and functional testing. If the alternate topological analysis approach is to be used, (see8.2.28.2.3) then a photomicrograph or composite mask drawing of the device is also needed.F1262M 1437.2 Radiation Simulation and Dosimetry Apparatus:7.2.1 Transient Radiation SourceA pulsed high
45、energy electron or bremsstrahlung source that can provide a dose rate inexcess of the upset response threshold level of the device being tested at the pulse width specified in the test plan is needed. Alinear accelerator (LINAC) with electron energies of 10 to 25 MeV is preferred (see Note 1), altho
46、ugh in some instances a flashX ray with end point energy above 2.0 MeV may be utilized (see Note 2 and Note 3). It is usually much more difficult tosynchronize a flash X-ray pulse with circuit operation, which limits the applicability of a flash X ray.NOTE 1Linac radiation pulses are made from a tra
47、in of discrete “micropulses” occurring at the linac radio frequency (RF). This high frequency pulsestructure could cause erroneous results for high frequency devices under test such as gallium arsenide. This has not yet been directly observed.test.NOTE 2The absorption coefficient of photons in silic
48、on and packaging materials is relatively flat at energies above 2 MeV, and has a nearly constantratio to the absorption coefficient of typical dosimetry systems. At lower energies absorption coefficients increase, which can introduce large dosimetryerrors if the end point energy in a bremsstrahlung
49、source is below 2.0 MeV.NOTE 3Because of dose enhancement and attenuation, a transport calculation is generally required to relate the dose at the region of interest in theDUT to the dosimetry used if a low energy flash X ray is used.7.2.2 Ionizing Dose Dosimetry SystemA dosimetry system such as a thermoluminescent dosimetry (TLD) system orcalorimeter that can be used to measure the absorbed ionizing dose produced by a single pulse of the radiation source is needed(see Practice E668).7.2.3 Pulse Shape MonitorA device for monitoring the shape of
