1、Designation: F 1394 92 (Reapproved 2005)Standard Test Method forDetermination of Particle Contribution from Gas DistributionSystem Valves1This standard is issued under the fixed designation F 1394; the number immediately following the designation indicates the year oforiginal adoption or, in the cas
2、e of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.INTRODUCTIONSemiconductor clean rooms are serviced by high-purity gas distribution systems. This test
3、methodpresents a procedure that may be applied for the evaluation of one or more components considered foruse in such systems.1. Scope1.1 This test method covers gas distribution system compo-nents intended for installation into a high-purity gas distribu-tion system.1.1.1 This test method describes
4、 a procedure designed todraw statistically significant comparisons of particulate gen-eration performance of valves tested under aggressive condi-tions.1.1.2 This test method is not intended as a methodology formonitoring on-going particle performance once a particularvalve has been tested.1.2 This
5、test method utilizes a condensation nucleus counter(CNC) applied to in-line gas valves typically used in semicon-ductor applications. It applies to automatic and manual valvesof various types (such as diaphragms or bellows), 6.3 through12.7-mm (14 through12-in.) size. For applications of this testme
6、thod to larger valves, see the table in the appendix.1.2.1 Valves larger than 12.7 mm (12 in.) can be tested bythis methodology. The test stand must be sized accordingly.Components larger than 12.7 mm (12 in.) should be testedwhile maintaining a Reynolds number of 20 000 to 21 000.This is the Reynol
7、ds number for 12.7-mm (12-in.) componentstested at a velocity of 30.5 m/s (100 ft/s).1.3 Limitations:1.3.1 This test method is applicable to total particle countgreater than the minimum detection limit (MDL) of thecondensation nucleus particle counter and does not considerclassifying data into vario
8、us size ranges.1.3.1.1 It is questionable whether significant data can begenerated from nondynamic components (such as fittings andshort lengths of tubing) to compare, with statistical signifi-cance, to the data generated from the spool piece. For thisreason, this test method cannot reliably support
9、 comparisonsbetween these types of components.1.3.1.2 If detection or classification of particles, or both, inthe size range of laser particle counter (LPC) technology is ofinterest, an LPC can be utilized for testing components. Flowrates, test times, sampling apparatus, and data analysis outlinedi
10、n this test method do not apply for use with an LPC. Becauseof these variations, data from CNCs are not comparable to datafrom LPCs.1.3.2 This test method specifies flow and mechanical stressconditions in excess of those considered typical. These condi-tions should not exceed those recommended by th
11、e manufac-turer. Actual performance under normal operating conditionsmay vary.1.3.3 The test method is limited to nitrogen or clean dry air.Performance with other gases may vary.1.3.4 This test method is intended for use by operators whounderstand the use of the apparatus at a level equivalent to si
12、xmonths of experience.1.3.5 The appropriate particle counter manufacturers oper-ating and maintenance manuals should be consulted whenusing this test method.1.4 The values stated in SI units are to be regarded as thestandard. The inch-pound units given in parentheses are forinformation only.1This te
13、st method is under the jurisdiction of ASTM Committee F01 onElectronics and is the direct responsibility of Subcommittee F01.10 on ProcessingEnvironments.Current edition approved Jan. 1, 2005. Published January 2005. Originallyapproved in 1992. Last previous edition approved in 1999 as F 139492(1999
14、).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priat
15、e safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific hazardstatements are given in Section 6, Hazards.2. Referenced Documents2.1 Federal Standard:FED-STD-209D Federal Standard Clean Room and WorkStation Requirements, Controlled Environment23
16、. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 background countscounts contributed by the testapparatus (including counter electrical noise) with the spoolpiece in place of the test object.3.1.2 condensation nucleus counter (CNC)light scatteringinstrument that detects particle
17、s in a gaseous stream bycondensing supersaturated vapor upon the particles.3.1.3 control productsample component that gives con-sistent, stabilized counts at or below the expected counts fromthe test components. The product is run periodically in accor-dance with the test protocol to ensure that the
18、 system is notcontributing particles significantly different from expectedlevels.3.1.3.1 DiscussionThe control product may have to bechanged periodically if its performance degrades with testing.Between tests, the control product must be bagged in accor-dance with the original manufacturers packagin
19、g and stored ina clean manner. The control product is used to allow the systemto consider the disruption caused by the activation of any valveunder test, such as significant fluctuations in flow, pressure,turbulence, and vibration.3.1.4 dynamic testtest performed to determine particlecontribution as
20、 a result of valve actuation.3.1.5 impact testtest performed to determine particlecontribution as a result of mechanical shock while the compo-nent is in the fully open position.3.1.6 sampling timethe time increment over which countsare recorded.3.1.7 sample flow ratethe volumetric flow rate drawn b
21、ythe counter for particle detection. The counter may draw higherflow for other purposes (for example, sheath gas).3.1.8 spool piecea null component consisting of a straightpiece of electropolished tubing and appropriate fittings used inplace of the test component to establish the baseline.3.1.9 stan
22、dard conditions101.3 kPa, 20C (14.73 psia,68F).3.1.10 static testa test performed on an as-received com-ponent in the fully open position. This test establishes particu-late contribution by the valve to the counting system.3.1.11 test durationtotal time required to complete thetest procedure.3.1.12
23、test flow ratevolumetric flow at test pressure andtemperature.3.1.13 test pressurepressure immediately downstream ofthe test component.3.1.14 test velocitythe average velocity of the test gas inthe outlet tube of the test valve (volumetric flow at ambientpressure and temperature divided by the inter
24、nal cross-sectional area of the valve outlet). In this test method, the testvelocity is specified to maintain a Reynolds number of 20 000to 21 000 (see the table in the appendix).3.2 Abbreviations:Abbreviation:3.2.1 LPClaser particle counter.4. Significance and Use4.1 The purpose of this test method
25、 is to define a procedurefor testing components intended for installation into a high-purity gas distribution system. Application of this test methodis expected to yield comparable data among components testedfor the purposes of qualification for this installation.4.2 Background TestingThis test met
26、hod uses backgroundtesting to ensure that the system is not contributing particlesabove a low, acceptable level. This ensures that counts seen arefrom the test device, not from a contaminated system. Thetechniques used to obtain background counts do not produceconditions identical to the conditions
27、existing when a testdevice is in place. It is recommended that the control productsbe run periodically to see that they give consistent results.These control products should be the lowest particle releaseproducts. They will be additional proof that the system is notcontributing excess particles duri
28、ng the static, dynamic, orimpact portions of the test.4.3 This test method can be used for testing lengths oftubing. The flow criteria will be identical to that indicated forvalves.Atubing test would only include the static background,the impact background, and the static and impact portions ofthe m
29、ethod.Adynamic portion could be added by actuating theupstream pneumatic valve (PV1), thus creating a flow surge tothe test length of tubing.5. Apparatus5.1 Test GasClean, dry nitrogen or air is to be used(minimum dryness 40C (40F) dew point at 689 kPa gagepressure (100 psig) and C, then the differe
30、nce is significantor,lD C, then the difference is not significant10.3.4 Sample calculations based on data shown in Figs.X1.1-X1.6.10.4 To determine if Valve A generated a significantlygreater number of particles (statistically) than backgroundduring the first 10 min of the static test:10.4.1 For the
31、 valve data during the first 10 min of the statictest:k = 47 counts,v = 0.00023 standard m3(0.5 standard ft3)l1= k/v = 94, ands12= k/v2= 188.10.4.2 For the background data during the first 10 min:k =3v = 0.00023 standard m3(0.5 standard ft3),l2= k/v = 6, andS22= k/v2= 12.Then: SD=(S12+ S22)1/2= (188
32、 + 12) = 14.14 and lD= l1 l2=946=88.10.4.3 The critical value in percent is calculated as:C98= ZbSD, where Zb= 2.08C98= 29.41, orC99= ZbSD, where Zb= 2.33C99= 32.95, orC99.9= ZbSD, where Zb= 3.17,C99.9= 44.82.10.4.4 lDis greater than the percent of C99.9; therefore, itcan be stated with 99.9 % confi
33、dence that Valve A generated asignificantly greater number of particles (statistically) thanbackground during the first 10 min of the static test.10.5 To determine if Valve B generated a significantlygreater number of particles (statistically) than Valve A duringthe first 10 min of dynamic testing:1
34、0.5.1 Applying the same calculations in percent as in 10.3to these two sets of data to determine that:lD= 114,C98= 102.5,C99= 114.8, andC99.9= 156.2.10.5.2 lDis greater in percent than C98but not greater thanC99; therefore, it can be stated with only 99 % confidence thatValve B generated a statistic
35、ally significant greater number ofparticles than Valve A during the first 10 min of dynamictesting.10.6 For comparing counts generated by a single valve tobackground counts, the data shown on the summary sheetshould be collected on each valve and the calculations per-formed. If more than one of the
36、same valve is tested, datashould be summed and calculations performed based on thetotal number of counts and volume sampled.10.7 For comparing counts generated by a single valve typeto counts generated by a different valve type, the data shown onthe summary sheet should be collected and the calculat
37、ionsperformed. If more than one of the same valve is tested, datashould be summed and calculations performed based on thetotal number of counts and volume sampled.10.8 Asummary of all confidence statements should accom-pany the data and be formulated as follows in Table 1:F 1394 92 (2005)610.9 A sum
38、mary of all confidence statements for compari-sons between valves should accompany the data and beformulated as follows in Table 2:11. Report11.1 Report the following test conditions:11.1.1 Date and time of test,11.1.2 Operator,11.1.3 Test flow rate, m3/s (standard ft3/min),11.1.4 Test pressure, kPa
39、 gage pressure (psig),11.1.5 Valve type, manufacturer, serial number, lot number,and model number,11.1.6 CNC manufacturer, serial number, sample flow rate,standard m3/s (standard ft3/min),11.1.7 Test gas type and dew point (C) model number, andcalibration date,11.1.8 Schematic of the test apparatus,
40、 including manufac-turers and model numbers of all test apparatus components,11.1.9 Calibration dates for the flow meters and the test dateshould also be reported (see Fig. X1.7 for sample data sheet).11.2 Data AcquisitionThe data link between the counterand any data acquisition system should be qua
41、lified andchecked for accuracy and consistency.11.3 Data Presentation:11.3.1 Graph the static, dynamic and impact portions of thetest separately as counts per min (measured by the counter)versus time, including the appropriate background measuredwith the spool piece in place) with each. Also graph t
42、he entiredata set as counts per min versus time. If different valves are tobe compared, graph their entire data sets together. (See Figs.X1.8-X1.11).11.3.2 Record and present the entire raw data set in tabularform as shown in Fig. X1.12, and Fig. X1.13,.12. Precision and Bias12.1 The precision and b
43、ias of the data generated by this testmethod is limited to the precision and bias of the particlemeasuring instruments utilized.13. Keywords13.1 condensation nucleus center; contamination; gas dis-tribution; gas distribution valves; isokinetic sampling; nitro-gen; particle contamination; particle co
44、unter; particles; semi-conductor processingTABLE 1 Particle Data Confidence Statement Summary SheetValve A generated more particles than background98 % Confident(Y/N)99 % Confident(Y/N)99.9 % Confident(Y/N)Static, first 10 min _ _ _Static, 60 min _ _ _Dynamic, first 10 min _ _ _Dynamic, 60 min _ _ _
45、Impact, first minute _ _ _Impact, first 10 min _ _ _Impact, 40 min _ _ _TABLE 2 Particle Data Confidence Statement Summary SheetValve B generated more particles than Valve A98 % Confident(Y/N)99 % Confident(Y/N)99.9 % Confident(Y/N)Static, first 10 min _ _ _Static, 60 min _ _ _Dynamic, first 10 min
46、_ _ _Dynamic, 60 min _ _ _Impact, first minute _ _ _Impact, first 10 min _ _ _Impact, 40 min _ _ _Valve A generated more particles than Valve B98 % Confident(Y/N)99 % Confident(Y/N)99.9 % Confident(Y/N)Static, first 10 min _ _ _Static, 60 min _ _ _Dynamic, first 10 min _ _ _Dynamic, 60 min _ _ _Impa
47、ct, first minute _ _ _Impact, first 10 min _ _ _Impact, 40 min _ _ _F 1394 92 (2005)7APPENDIX(Nonmandatory Information)X1. Additional Test DataX1.1 See Table X1.1 and Figs. X1.1-X1.13.TABLE X1.1 Matrix of Typical Test Flow Rates Nominal Outside Diameters0 TestComponentNominalDiameter, in.1 TestCompo
48、nentOutlet InsideDiameter, in.2 ReynoldsNumber3 AverageTest Velocity,ft/s4 TestFlow Rate,ft3/min114 0.180 20 600 224 2.4238 0.305 20 600 132 4.0312 0.402 20 600 100 5.3434 0.652 20 600 62 8.65 1 0.870 20 600 46 11.46 2 1.870 20 600 22 25.20 TestComponentNominalDiameter, in.5 ExpansionCone InsideDiameter,in.6 SampleTube InsideDiameter80.10 ft3/
