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From:
Doug Pauls <[log in to unmask]>
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TechNet Mail Forum.
Date:
Mon, 20 Oct 1997 10:36:17 -0400
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text/plain (193 bytes) , LAY2W60.DOC (64 kB)
Fulton,
The attached file is in Word 6.0 format.  You may need to MIME decode the
document if your e-mail reader does not do this automatically.  If you can't
read it, I will send a paper copy.

Doug.



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;}\listid1807360041}}{\*\listoverridetable{\listoverride\listid-2\listoverridecount1{\lfolevel\listoverrideformat{\listlevel\levelnfc23\leveljc0\levelfollow0\levelstartat1\levelold\levelspace0\levelindent360{\leveltext\'01\u-3913 ?;}{\levelnumbers;}\f3\fbias0 \fi-360\li360 }}\ls1}{\listoverride\listid-2\listoverridecount1{\lfolevel\listoverrideformat{\listlevel\levelnfc23\leveljc0\levelfollow0\levelstartat1\levelold\levelspace0\levelindent360{\leveltext\'01\u-3913 ?;}{\levelnumbers;}\f3\fbias0 \fi-360\li360 }}\ls2}{\listoverride\listid1807360041\listoverridecount0\ls3}{\listoverride\listid-2\listoverridecount1{\lfolevel\listoverrideformat{\listlevel\levelnfc23\leveljc0\levelfollow0\levelstartat1\levelold\levelspace0\levelindent360{\leveltext\'01\u-3913 ?;}{\levelnumbers;}\f3\fbias0 \fi-360\li360 }}\ls4}}{\info{\title Schmuck II: Son of Schmuck}{\author Douglas Pauls}{\operator Douglas Pauls}{\creatim\yr1997\mo10\dy17\hr12\min51}{\revtim\yr1997\mo10\dy17\hr12\min51}{\version2}{\edmins1}{\nofpages14}{\nofwords5005}{\nofchars28533}{\*\company CSL, Inc.}{\nofcharsws35040}{\vern71}}\margr1080 \widowctrl\ftnbj\aenddoc\lytprtmet\formshade\viewkind1\viewscale100\pgbrdrhead\pgbrdrfoot \fet0\sectd \psz1\linex0\endnhere\sectdefaultcl {\footer \pard\plain \qr\nowidctlpar\widctlpar\adjustright \f1\cgrid {\cgrid0 Page }{\field{\*\fldinst {\cgrid0 PAGE }}{\fldrslt {\lang1024\cgrid0 1}}}{\cgrid0 of }{\field{\*\fldinst {\cgrid0 NUMPAGES }}{\fldrslt {\lang1024\cgrid0 14}}}{\v \pnseclvl1\pnucrm\pnstart1\pnindent720\pnhang{\pntxta .}}{\*\pnseclvl2\pnucltr\pnstart1\pnindent720\pnhang{\pntxta .}}{\*\pnseclvl3\pndec\pnstart1\pnindent720\pnhang{\pntxta .}}{\*\pnseclvl4\pnlcltr\pnstart1\pnindent720\pnhang{\pntxta )}}{\*\pnseclvl5\pndec\pnstart1\pnindent720\pnhang{\pntxtb (}{\pntxta )}}{\*\pnseclvl6\pnlcltr\pnstart1\pnindent720\pnhang{\pntxtb (}{\pntxta )}}{\*\pnseclvl7\pnlcrm\pnstart1\pnindent720\pnhang{\pntxtb (}{\pntxta )}}{\*\pnseclvl8\pnlcltr\pnstart1\pnindent720\pnhang{\pntxtb (}{\pntxta )}}{\*\pnseclvl9\pnlcrm\pnstart1\pnindent720\pnhang{\pntxtb (}{\pntxta )}}\pard\plain \s16\qc\nowidctlpar\widctlpar\adjustright \b\f1\cgrid {The Layman\rquote s Guide to Qualifying A Process to J-STD-001B \par }\pard\plain \nowidctlpar\widctlpar\adjustright \f1\cgrid { \par }\pard \qc\nowidctlpar\widctlpar\adjustright {Douglas Pauls \par Contamination Studies Laboratories \par \par }\pard \nowidctlpar\widctlpar\adjustright {\ul Introduction \par }{\tab Electronics manufacturers are faced with the difficult task of proving that a candidate manufacturing process can produce acceptable hardware, either to the customer of the product, or for internal quality control. In the past, assembly level specifications (e.g. MIL-STD-2000A) told you exactly how to go about this demonstration. It wasn\rquote t always precisely correct, but you didn\rquote t have to figure our all of the fine points of the qualification on your own. In our modern era, \ldblquote how-to\rdblquote specifications are now evil things and taboo to all involved with them. The users now have to determine many of the process qualification steps on their own, and sadly, many don\rquote t have the faintest idea where to start. That is the purpose of this document. It makes no assumptions about what you know and leads you through the somewhat complex task of qualifying a candidate process to the B revision of J-STD-001. \par \par }{\ul Who Am I?}{ \par \tab So, who died and made me Grand Wazoo? My name is Doug Pauls and I am Technical Director of Contamination Studies Laboratories. I have been involved with MIL-STD-2000, J-STD-001, and many other IPC technical activities. Much of my writing was the basis for J-STD-001A, Appendix D, and I have been actively involved with the B revision to J-STD-001. Since I have been involved with the development of these assembly documents, and because I regularly counsel assemblers who must qualify new processes, I undertook this writing to assist process professionals faced with qualifying their process. The above self-aggrandizing wording was not done to brag, but to illustrate some of my credentials. \par \tab I should probably warn you that there is some rather warped humor contained herein. I find that humor makes a document more readable and a little less \ldblquote dry\rdblquote . Some feel it unprofessional; I don\rquote t. \par \tab I have included a short bibliography (attached) of other articles that would be helpful in qualifying a manufacturing process. \par \par }{\ul When Do I Do This Testing? \par }{\tab Often, the first decision that a process engineer must make is if the new process }{\ul must}{ be qualified. I\rquote ll give you my favorite engineering answer - it depends. The biggest driving factor is the customer of your product. What test data or test protocol do they desire in order to feel comfortable with the new process? If your customer wants MIL-STD-2000A, Appendix A testing, that\rquote s what you do. If they want J-STD-001A, Appendix D testing, that\rquote s what you do. Unfortunately, this assumes that your customer is knowledgeable about what testing to specify. Often, a customer has no more idea of what to specify than you do. There is an incredibly wide learning curve in the industry. \par }\pard \fi720\nowidctlpar\widctlpar\adjustright {A question that is asked frequently by military manufacturers is \ldblquote What testing do I do now that MIL-STD-2000A has been canceled without replacement?\rdblquote The answer is MIL-STD-2000A, Appendix A, unless told otherwise by your contract officer. The contract officer is in somewhat of a quandary, since there is a DoD mandate that they be \ldblquote silent\rdblquote on the issue of soldering. \par My specialty is not contractual law, but my understanding is that the day you signed the contract, the revision in place at that time is the revision you manufacture to. Any changes that come later are immaterial unless the contract is upgraded to the new revision. If you still manufacture to MIL-STD-2000A and the contracts have not been changed, then you still have to do Appendix A testing if you want to use a new process. \par }\pard \nowidctlpar\widctlpar\adjustright {\tab The second most asked question, with respect to J-STD-001B (J1B) is \ldblquote If I qualified to the A revision (J1A), must I repeat the testing to qualify to J1B?\rdblquote . The answer is no, there is a grandfather clause. See the note in paragraph 4.2 of J1B. \par \tab In previous process qualification protocols, you were given a set of instructions on what vehicle to use, how to process it, how to test it, etc. With J1B, rather than a task list, the assembler is faced with a series of choices to be made (oh, joy). \par \par }{\b Choice #1.\tab When must I do Appendix D qualification testing? \par }{ \par There are three instances where the testing in Appendix D is required. \par \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls1\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls1\adjustright {When your customer requires it. After all, your customer drives the bus, even if they don\rquote t have a road map and should not have a license. \par }\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl12\ls0\pnrnot0\pndec }\ilvl12\adjustright { \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls1\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls1\adjustright {When your customer feels that the Appendix D testing is the only acceptable way to demonstrate the Materials Compatibility requirement of J-STD-001B, paragraph 3.4. \par }\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl12\ls0\pnrnot0\pndec }\ilvl12\adjustright { \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls1\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls1\adjustright {If you are using a flux that is not contained in the following J-STD-004 designations: ROL0, ROL1, REL0, REL1, ORL0, or ORL1 (cleaned). This requirement is found in J-STD-001B, paragraph 4.2. \par }\pard \nowidctlpar\widctlpar\adjustright { \par Let us look at each one of these in turn. \par \par }{\ul When your customer requires it}{. Your customer may read over the specification and conclude that Appendix D testing is required in order to be compliant to J-STD-001B. This is not the case, but we have all been in situations where the customer is dead wrong, but we still have to do it his way. It may be necessary to educate your customer on when it is appropriate to require the Appendix D protocol and when it is more appropriate to use other test data. More on this later. \par \par }{\ul Materials Compatibility Demonstration}{. Section 3.4 tells you, the assembler, that all of the materials and processes you use should be compatible with each other. A good, sound policy. Let us look at the wording of paragraph 3.4 and see how it relates to Appendix D testing. \par \par }{\i The materials and processes used to assemble / manufacture electronic assemblies MUST be selected such that their combinations produce products acceptable to this standard. Objective evidence of this compatibility SHALL be maintained and available for review. When major elements of the proven processes are changed, (e.g. flux, solder paste, cleaning media or system, solder alloy or soldering system) validation of the acceptability of the change(s) MAY be performed and documented in accordance with Appendix D. These process changes can involve a change in one of the process steps. They can also pertain to a change in board supplier, solder mask or metalization.}{ \par \par The first sentence is what in the spec writing business is called a \ldblquote motherhood and apple pie statement\rdblquote . If you manufacture electronic assemblies, you have to choose materials and processes that are compatible with each other. The use of MUST means this is a requirement for everyone. Notice, there is no mention yet of how such compatibility is demonstrated. This is a reasonable requirement for everyone. If you have not sat down and examined how each and every step in the process impacts the quality of your assembly, you should. Incompatible materials and processes are one of the leading causes of assembly failure in the field. \par \par }{\i Objective evidence of this compatibility SHALL be maintained and available for review.}{ \par \par The second sentence says that you are required, if you are building class 3 hardware, to have }{\ul some}{ documented evidence that your materials and processes are compatible. The use of the word SHALL means its required for class 3 and highly recommended (but not required) for class 1 or 2. Still no mention of how the compatibility is to be demonstrated. If you desire to do the Appendix D protocol, that is an acceptable way to demonstrate compatibility. On the other hand, if you wanted to use some alternative demonstration of compatibility, for example an ion chromatography evaluation, there is nothing in the wording here that says you can\rquote t or that it is less valid than Appendix D. The intent is that you have some data that shows your materials and processes are compatible; how you do it is up to you. \par \par }{\i When major elements of the proven processes are changed, (e.g. flux, solder paste, cleaning media or system, solder alloy or soldering system) validation of the acceptability of the change(s) MAY be performed and documented in accordance with Appendix D. \par }{ \par The third sentence can strike very deeply into the pockets of the assembler, depending on the interpretation. Consider all the potential changes implied that could cause you to repeat the Appendix D protocol or other compatibility testing. Changes in: fabricator, solder mask, metalization, laminate, flux, paste, reflow profiles, wave profiles, cleaning chemistry, cleaning parameters, coating types, coating thinners. The last sentences of 3.4 show such changes as cause for re-testing. Yes sir, I could retire a very rich man after a few years of this continual re-testing. Unfortunately for my Swiss bank account, the use of the term MAY removes it as a requirement for anyone. The third sentence could now alternatively read \ldblquote If you change anything in the process, it would be a real good idea to do some testing to make sure the change you implemented is not detrimental to your product\rdblquote . Do you HAVE to do it? No. Should you do some form of testing? Yes, you should, if for nothing more than your peace of mind. Must it be Appendix D? Not necessarily. An alternative demonstration could be used. \par \par The third sentence of 3.4 is the weakest (in contractual strength) of the paragraph. Appendix D testing MAY be used to show process compatibility. Oh, thanks. It would have been fairly pointless to generate an Appendix D protocol for the document if it }{\ul wasn\rquote t}{ an acceptable demonstrator of compatibility. All this sentence tells you is that Appendix D is an acceptable demonstrator. This could be useful if you have already done Appendix D testing, but someone else wants you to do an alternate protocol to demonstrate compatibility. You could then show your Appendix D report and say that your compatibility has already been acceptably demonstrated. So there. \par \par In summary, everyone should check for compatibility. Only class 3 assemblers are required to show compatibility. Anyone can use Appendix D to demonstrate compatibility, but alternative methods are perfectly acceptable too. Of course, your customer could throw this entire discourse into a cocked hat by requiring you to do Appendix D testing. Get used to this idea, I use it a lot. \par \par Now, if your customer does specify that you have to do Appendix D as a demonstrator of materials and process compatibility, you need to come to a very specific understanding on what kinds of changes in the process require, in his/her eyes, a repeat of the Appendix D (or other) testing. How much latitude on reflow or cleaning parameter variation? Can you change to another paste or flux that is highly similar to the qualified flux (e.g. going from a 5% solids to a 3% solids of the same flux)? If your customer requires Appendix D testing for every minor variation, I might just be able to afford that yacht yet. \par }{\ul \par The Choice of the Flux}{. J-STD-001B, paragraph 4.2 reads: \par \par }{\i Flux MUST be in accordance with J-STD-004. Flux shall conform to flux activity levels L0 or L1 of flux materials rosin (RO), resin (RE), or organic (OR), except organic flux activity level L1 SHALL not be used for no-clean soldering. When other activity levels or flux materials are used, data demonstrating compliance with testing of Appendix D SHALL be available for review. \par \par Note: Flux or solder paste soldering process combinations previously tested or qualified in accordance with other specifications do not require additional testing per paragraph 4.2. \par \par Type H fluxes may be used for tinning of terminals, solid wire and sealed components when performed as part of an integrated fluxing, soldering, cleaning, and cleanliness test system. \par }{First off, to be compliant to J1B, you have to use fluxes and paste fluxes (solder pastes) that meet the minimum qualification criteria of J-STD-004. Since this is a commercial document, there is no Qualified Products Listing (QPL). You would have to obtain a test report from the flux vendor or an independent laboratory showing the flux to be compliant to J-STD-004, Amendment 1. Most flux vendors should have such a report on file. If not, push them. I would suggest, in the strongest possible terms, that you not use a flux or solder paste not qualified to this standard. If the vendor won\rquote t spend the bucks to qualify it, don\rquote t consider it. \par \par If you look at J-STD-004, Amendment 1, there are four flux types: Rosin (RO), Resin (RE), Organic Acid (OR), and Inorganic Acid (IN). This generally refers to the primary constituent of the solids in the flux. Fluxes are further classified by activity: Low (L), Medium (M), and High (H), which is an indicator of the aggressiveness of the flux. Low activity fluxes are usually benign, while high activity fluxes are very corrosive. Fluxes are also classified as halide free (designation 0) or containing halides (designation 1). A common no-clean flux, such as Kester 951, might have a designation as ROL0, which indicates that the solids are rosin based, low activity, and contains no halides. \par \par So, what does this mean relative to Appendix D? For most no-clean manufacturers, it means you don\rquote t have to do Appendix D to be compliant. If I am using a flux or paste from this list, the material is assumed to be benign enough to be used safely (a somewhat shaky assumption to my way of thinking). \par \par ROL0 - Rosin, Low activity, no halides \par ROL1 - Rosin, Low activity, some halides \par REL0 - Resin, Low activity, no halides \par REL1 - Resin, Low activity, some halides \par ORL0 - Organic Acid, low activity, no halides. Example: Adipic Acid \par ORL1 (if you clean it) - Organic Acid, low activity, halide containing. \par \par If the flux you are using is not in the above list, then you have to do Appendix D testing. No way around it. Most water soluble fluxes and many of the RMA/RA fluxes are Medium and High activity levels, so Appendix D testing is required. The higher you go in flux activity, the more dangerous the flux residues become, and the greater the need to demonstrate that you can handle the materials well. \par \par The good news is that if you are going to a no-clean process, most of the no-clean fluxes and pastes on the market today fit into the first four designations above. \par \par Of course, if the customer still wants you to show Appendix D testing for a ROL0 flux, guess what you get to do…….. \par \par \par \par Another \ldblquote out\rdblquote for many manufacturers comes as part of the Note. If you already spent the bucks to qualify the manufacturing process to MIL-STD-2000A, J-STD-001A, WS-6536E, etc., you are not required to retest. This grandfather clause was added since the B revision of J-STD-001 follows so closely on the heels of the A revision. \par \par Now that you are aware of some of the \ldblquote weasel-wording\rdblquote of the specification, and when you must or may do Appendix D testing, let\rquote s take a look at how would I do the testing, if I were in your shoes. First, unless your feet were size 10D, I wouldn\rquote t be in your shoes, but that\rquote s besides the point. \par \par }\pard\plain \s4\nowidctlpar\widctlpar\outlinelevel3\adjustright \b\f1\ul\cgrid {CSL Recommended Approach \par }\pard\plain \nowidctlpar\widctlpar\adjustright \f1\cgrid { \par The first step is to get buy-in from your customer(s), as they drive your bus. The most critical things to agree upon are the number of sub-studies and the depth of each sub-study that will support the final Appendix D qualification. Why do I say the \ldblquote final\rdblquote qualification? \par \par The entire philosophy of Appendix D is that it represents the end-point of your process development work and represents your \ldblquote best-shot\rdblquote combination of materials and processes. Frankly, Appendix D can be very expensive. Don\rquote t even think of using it (as printed) as a screening experiment protocol. Let\rquote s take an example. \par \par Whozits Corporation has four bare board vendors. Each vendor can use one of two approved solder mask formulations. So we are up to eight possible combinations of vendor and solder mask. Each vendor might use either OSP coated copper or HASL. Now we are up to sixteen combinations and we haven\rquote t even seen the assembly process. \par \par Let\rquote s say I want to test 3 solder pastes. Combinations = 48. Three fluxes. Combinations = 144. Two cleaning options - 288. Two possible conformal coatings - 576. At ten samples each for SIR, that gives us a total SIR test sample set of 5760 test boards. This would be months of testing and at least 4-5 large humidity chambers. \par \par You can see why independent test lab moguls salivate at the mere thought! \par \par }{\b\ul Choice #2 - Foundational Studies}{ \par \par So, how to proceed? All previous process qualification protocols, such as MIL-STD-2000A or J-STD-001A, had you use a pre-cleaned standard test board, such as the IPC-B-36, with no solder mask and bare copper metalization. J-STD-001B now factors in the concern for fabrication residues, solder mask, metalization, and eliminates pre-cleaning. So the logical place for the first sub-study is with your fabricators and your bare boards. \par \par \par Bare board cleanliness can be important to the quality of your end-product and is crucial if you are going into the no-clean realm. Even if you have the finest assembly process in the world, the quality of your products are held hostage to the quality of your incoming bare boards. If that isn\rquote t a sobering thought, it should be. \par \par The question has already been asked \ldblquote Must I do Appendix D for every fabricator-mask-metalization combination I use?\rdblquote Frightening thought, eh? Especially if you have never benchmarked the true cleanliness of your fabricators product or have a large number of fabricators. \par \par The first step should be a benchmarking of the residues present on your bare boards, using a rigorous chemical analytical technique. Standard Omegameter testing would not fit in this category. For bare board analysis, ion chromatography (TM-650, method 2.3.28) is recommended. Ion chromatography allows us to identify not only what ionic species are present, but also the amounts. Different assemblies will have different sensitivities to various ionic species, but with a sufficient experience base, a skilled analyst can usually give a good indication of whether the fabrication residues will cause problems in SIR testing. The substrate used for the analysis should be actual bare boards that approximates your most difficult or demanding situation. \par \par As a possible alternative, you could also do a modified ROSE test if you have access to one of the ionic cleanliness testers that uses heated isopropanol and water (e.g. Omegameter 600SMD). The method was published in the March 1997 edition of the IPC Technical Review. We can furnish copies of this method, if desired. This modified method uses a longer extraction time and temperature, so more harmful materials are extracted for analysis. Ion chromatography is still preferred, but you can do your own preliminary studies with the modified ROSE test. \par \par After you have performed the residue analysis for the various bare board vendors, it would be prudent to choose the worst, or dirtiest, case. Most qualification protocols have the underlying theme that if you can pass the requirements with your most difficult case, then the less stringent cases should also pass. If your customer should ask at a later time whether the data is representative, the study can be produced that shows you used the worst case. \par \par This then begs the question of how do you determine worst case? What mask to use and what metalization? From a residue standpoint, this is my opinion: \par \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar\jclisttab\tx360{\*\pn \pnlvlblt\ilvl0\ls3\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls3\adjustright {Dry films < wet-screenable masks < liquid photoimageables (LPIs) \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar\jclisttab\tx360{\*\pn \pnlvlblt\ilvl0\ls3\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls3\adjustright {Hot air solder leveling (HASL) with a chloride based fluid < HASL with a brominated fluid < organic solder preservative < alternative finishes (e.g. palladium flash) \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar\jclisttab\tx360{\*\pn \pnlvlblt\ilvl0\ls3\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls3\adjustright {Through-hole < mixed technology < surface mount \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar\jclisttab\tx360{\*\pn \pnlvlblt\ilvl0\ls3\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls3\adjustright {Ceramic substrates < FR-4 < CEM , polyimide \par }\pard \nowidctlpar\widctlpar\adjustright { \par So, if you can pass the test with a ceramic-based through-hole board, masked with a dry film and HASLed with a chlorinated flux, the rest should be piece of cake. \par \par }\pard\plain \s1\keepn\nowidctlpar\widctlpar\outlinelevel0\adjustright \b\f1\ul\cgrid {Choice #3: The Test Vehicle \par }\pard\plain \nowidctlpar\widctlpar\adjustright \f1\cgrid { \par Now that you have chosen which fabricator(s) to use, you must select the test vehicle. The default test vehicle is the IPC-B-36 standard test assembly. The manufacturer must determine how representative the B-36 is of the actual product. In many cases, the B-36 is significantly different from actual product. There are other test vehicles available in the industry for use as a qualification vehicle, or you can design your own vehicle (its not that hard). Other vehicles include: \par \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {Boeing qualification board (primarily PTH) \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {NASA Test Assembly (mixed technology) \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {Low Residue Soldering Task Force (LRSTF) test assembly (mixed technology) \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {ARPA ETC\rquote 96 Test Board (mixed technology) \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {Series of boards from TopLine (e.g. Sabre boards) \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {Solectron board \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {Not recommended - IPC-B-24, IPC-B-25, IPC-B-25A \par }\pard \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright { \par Whatever is chosen, the vehicle must have the following characteristics. \par \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {The vehicle must be representative of the product and be amenable to SIR testing \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {The test patterns and components must be representative of the hardest / greatest challenge on your product, e.g. if you do 15 mil pitch SMT, your test vehicle should have 15 mil pitch. \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {It should contain the same material mix as on your product, e.g. if your product has tin-lead SMOBC on FR-4, your test vehicle should too. \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls4\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls4\adjustright {The SIR test patterns under the components must not be covered with solder mask \par }\pard \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright { \par You will need to know the number of \ldblquote squares\rdblquote in the representative SIR test patterns to determine the SIR pass fail numbers related back to the IPC-B-36 test board. IPC-TR-467 can give you more information on squares count. I would present it here, but discussing \ldblquote squares\rdblquote makes my head hurt. The design of an SIR test vehicle is a topic in itself. More information on the salient characteristics in an SIR test vehicle can be found in IPC-9201, the SIR Handbook. \par \par }\pard\plain \s1\keepn\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel0\adjustright \b\f1\ul\cgrid {Choice #4: Solder Mask and Metalization \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid { \par Now you have your fabricator chosen and your fabricator now has your Gerber files for the test board in hand. You must choose the solder mask and metalization that will go on your test assembly. At this point, the following question will probably be raised: \par \par \ldblquote Do I need to do qualification testing for every combination of solder mask and metalization?\rdblquote \par Again, potentially yes and potentially very expensive. Just as before, you should look very hard at your mix of solder masks. Do you really need that many? The same thought applies for the metalization involved. If most of your product is liquid photoimageable (LPI), then that is what should go on your vehicle. If most of your product is HASLed, then your test vehicles should be as well. \par \par The selection of solder mask and metalization should be from a designed study. If you are trying to use the \ldblquote worst case\rdblquote approach, a designed study is the only way to do so. At some point in the future, it is likely that your customer will want to see data on how you chose the mask-metalization combination for testing. A scientific study looks much better than showing them the dart board. In such a study, ion chromatography would be an acceptable test method. \par \par }\pard\plain \s1\keepn\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel0\adjustright \b\f1\ul\cgrid {Choice #5: Fabricating the Vehicles \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid { \par Now that you have chosen the fabricator, laminate, solder mask, and metalization, it is time for your fabricator to make the test boards. The boards should be made in the same way as your product. There must also be no special cleaning steps (precleaning) that are not part of the normal fabrication process. \par \par You will need to know the number of boards to be made. You will need to have 10 test samples for each combination of materials and processes that you wish to qualify. Example: if you have chosen one product line of CEM-1, LPI mask, tin-lead and a second product line of FR-4, LPI mask, OSP coated, to go through your assembly process, then you will need 20 boards (at least). Ten boards for the first product line and ten boards for the second product line. \par \par Since you get better prices from volume discounts, order lots. You can use the other boards for preliminary studies and for the inevitable goofs in manufacturing. \par \par }\pard\plain \s1\keepn\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel0\adjustright \b\f1\ul\cgrid {Choice #6: Assembly Process \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid { \par Now you have the fabricated test boards, and presumably the test components, in house, ready to subject them to the assembly process. The rule to follow is \ldblquote if your product sees it, the test board sees it\rdblquote . This includes exposure to mounting adhesives, temporary solder masks, solder paste, solder flux, hand soldering with cored wire solder (and additional flux if that\rquote s what you do on product). Any interim cleaning steps, such as brushing with isopropanol, or a final cleaning prior to conformal coating, must also be performed. \par \par A caution is presented regarding the components used in this evaluation. Presumably your test vehicle will have components, such as a 15-mil pitch QFP. If some of your test patterns are interdigitated mounting pads (such as M2 and M4 on the B-36), then any internal circuitry on the component can result in poor SIR readings. Whatever components are used, they need to be dummy components with no internal die if it is part of the SIR measurement. Be cautious of TopLine Components, who sell dummy components. They do not have a separate part number for dummy components with no internal dies. Components with no internal dies are a special order item. \par \par If you have numerous assembly processes, you should ask yourself if you can streamline those processes to fewer combinations. You will need to process a set of 10 boards for each assembly process you wish to qualify. \par \par }\pard\plain \s1\keepn\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel0\adjustright \b\f1\ul\cgrid {Choice #7: Conformal Coating \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid { \par Now you must choose whether or not to conformally coat the test boards prior to SIR testing. If your product is coated, the test board is coated. If you do not conformally coat the product, then the test board is not coated. Again, you face the potential of having to do the testing for all your coatings, and determining if you need all those coatings. Each coating can represent a harmful interaction with existing residues. Only preliminary studies can determine if there are hazardous situations with any of your coatings or coating processes. For this set of preliminary studies, SIR testing is preferred over ion chromatography testing. \par \par One note of caution from a test lab professional, if you coat the entire board, including the points we need to attach to for SIR testing, and we have to then scrape the coating off to get a good connection, we scream loudly and go for your pocketbook. You may need to mask off these connection points during the coating process or include test lead attachment as part of the assembly process. A competent test lab should be able to assist with this area (I know of a good one in Kokomo). \par \par }\pard\plain \s1\keepn\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel0\adjustright \b\f1\ul\cgrid {Choice #8: The Test Environment \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid { \par The last choice that you have to make is the choice of the SIR test environment: cyclic (IPC-TM-650, method 2.6.3) or static (method 2.6.3.3B). The cyclic method has the environment cycle between 25C and 65C, 90% RH, three times per day, for ten days. This method simulates a condensing environment and is most applicable to product that will likely see condensation during it\rquote s life cycle. The static method has a constant 65C / 85% RH environment over a 7 day period. This method is more applicable for testing for corrosion and metal migration in uncoated product, or for product where condensation is not likely. \par \par While the choice is up to you, it is recommended that the coated boards be tested with the cyclic profile and the uncoated boards be tested with the static method. \par \par \par \par \par \par }\pard\plain \s3\keepn\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel2\adjustright \b\i\f1\ul\cgrid {\i0 Choice #9: The SIR Test \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid { \par Unfortunately, SIR testing is still a technique dependent test. IPC-9201 can help educate both the tester and the manufacturer on the many factors which affect SIR testing. This becomes important now because the pass-fail criteria for SIR testing includes the }{\ul variability}{ of your data set as a factor. In previous SIR qualification protocols, all you were concerned about was a minimum value. If you had a wide variation to the data, it did not make a difference. Now it does. The pass-fail criteria looks at both minimum values and the standard deviation of the data set. \par \par Choose a test lab that knows SIR testing well. They should be able to show you how controlled their chambers are; repeatability studies for SIR, calibration data for SIR, chamber water cleanliness, etc. \par \par Why should you be concerned about all of these things? If your SIR tester does not know what he/she is doing, the test variability can overshadow all the work you have done in the process development. A poor test technique could fail your qualification more than your process parameters. \par }{\b\ul \par }\pard\plain \s3\keepn\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel2\adjustright \b\i\f1\ul\cgrid {\i0 Calculating the Pass Fail Criteria \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid { \par }\pard \nowidctlpar\widctlpar\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {All of the pass-fail SIR criteria for J1B is related back to a comparable pattern on the IPC-B-36 test board. Let us say that we use a simple test PWB with only one SIR pattern per PWA; a \ldblquote Y\rdblquote pattern under the most difficult to clean part on each test assembly. This \ldblquote Y\rdblquote pattern has a \ldblquote gap\rdblquote \par \par \tab 25.4 mm long * .635 mm spacing = 25.4/0.635 = 40 squares \par }\pard \fi2070\nowidctlpar\widctlpar\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {(1 inch long * 0.025 inch spacing = 40 squares) \par \par }\pard \nowidctlpar\widctlpar\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {The equivalent pattern for a B-36 would be pattern M6, M7, M9, or M10. Each of these patterns have the same pattern characteristics: \par \par \tab 68.58 mm long * 0.152 mm spacing = 68.58 / 0.152 = 450 squares \par \tab \tab \tab (2.7\rdblquote long * 0.006\rdblquote spacing) \par \par Our new pass-fail level for our \ldblquote Y\rdblquote pattern = 100 megohms * (450 / 40) = 1,125 megohms or 9.05 on the log scale. \par }\pard \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\page \par }{\b\i\ul Example Data Set \par }{ \par }\trowd \trrh247\trleft-180\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw30 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx540\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1012\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1966\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx2892\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx3818\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx4725\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx5635\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx6545\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx7364\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx8274\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw30 \cltxlrtb \cellx9184\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 Process\cell PWA\cell T0\cell M1\cell M2\cell M3\cell M4\cell M5\cell M6\cell M7\cell TF\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\trowd \trrh247\trleft-180\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw30 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx540\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1012\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1966\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx2892\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx3818\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx4725\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx5635\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx6545\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx7364\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx8274\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw30 \cltxlrtb \cellx9184\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 101\cell 3.21E+13\cell 6.54E+10\cell 5.16E+10\cell 4.65E+10\cell 4.10E+10\cell 3.39E+10\cell 2.75E+10\cell }{\b\fs18\cf1 2.26E+10\cell }{\fs18\cf1 7.77E+11\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 102\cell 7.08E+12\cell 2.01E+10\cell 2.23E+10\cell 2.17E+10\cell 2.01E+10\cell 1.86E+10\cell 1.69E+10\cell }{\b\fs18\cf1 1.56E+10\cell }{\fs18\cf1 1.12E+12\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 103\cell 1.21E+12\cell }{\b\fs18\cf1 4.00E+09\cell }{\fs18\cf1 4.23E+09\cell 4.18E+09\cell 4.23E+09\cell 4.14E+09\cell 4.09E+09\cell 4.03E+09\cell 4.68E+11\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 104\cell 4.21E+11\cell 1.32E+10\cell 1.56E+10\cell 1.51E+10\cell 1.45E+10\cell 1.38E+10\cell 1.32E+10\cell }{\b\fs18\cf1 1.29E+10\cell }{\fs18\cf1 1.78E+12\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 105\cell 9.40E+11\cell 1.16E+10\cell 1.18E+10\cell 1.05E+10\cell 9.57E+09\cell 8.74E+09\cell 7.98E+09\cell }{\b\fs18\cf1 7.45E+09\cell }{\fs18\cf1 5.09E+11\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 106\cell 3.62E+13\cell 2.94E+10\cell 1.33E+10\cell 6.30E+09\cell 4.56E+09\cell 3.04E+09\cell }{\b\fs18\cf1 2.85E+09\cell }{\fs18\cf1 2.86E+09\cell 1.13E+12\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 107\cell 6.73E+12\cell 6.24E+11\cell 3.57E+11\cell 4.31E+10\cell 1.63E+10\cell 9.59E+09\cell 7.90E+09\cell }{\b\fs18\cf1 6.91E+09\cell }{\fs18\cf1 3.42E+12\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 108\cell 7.33E+12\cell 6.12E+11\cell 1.94E+11\cell 8.96E+10\cell 5.65E+10\cell 4.13E+10\cell 2.80E+10\cell }{\b\fs18\cf1 2.28E+10\cell }{\fs18\cf1 3.08E+12\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 109\cell 5.13E+12\cell 1.83E+10\cell 1.65E+10\cell 1.53E+10\cell 1.45E+10\cell 1.37E+10\cell 1.29E+10\cell }{\b\fs18\cf1 1.27E+10\cell }{\fs18\cf1 3.49E+12\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\trowd \trrh247\trleft-180\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw30 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx540\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1012\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1966\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx2892\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx3818\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx4725\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx5635\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx6545\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx7364\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx8274\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw30 \cltxlrtb \cellx9184\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs18\cf1 C\cell 110\cell 8.26E+11\cell 1.03E+10\cell 1.25E+10\cell 1.17E+10\cell 1.10E+10\cell 1.01E+10\cell 9.42E+09\cell }{\b\fs18\cf1 9.05E+09\cell }{\fs18\cf1 4.66E+13\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright { \par Let us say that the above table is the data generated for our 10 test boards. T}{\sub 0}{ represents initial ambient measurements. T}{\sub f}{ represents final ambient measurements. All other measurements are made at the elevated temperature and humidity conditions of the chosen test method. We are interested only in the minimum values for the test pattern over the course of the test. Those values appear in bold face. If we made a table of these minimum (also called WetMin) numbers, we would have the following. \par \par }\trowd \trqc\trgaph29\trrh247\trleft-728\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw30 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx335\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx933\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1954\clvertalt\clbrdrt\brdrs\brdrw30 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw30 \cltxlrtb \cellx3178\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\b\fs20\cf1 Process\cell PWA\cell WetMin\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\b\fs20\cf1 LogOhm\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\b\f16\cf1 \row }\trowd \trqc\trgaph29\trrh247\trleft-728\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw30 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx335\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx933\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1954\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw15 \clbrdrr\brdrs\brdrw30 \cltxlrtb \cellx3178\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 101\cell }{\fs20 2.26E+10\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 10.35\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 102\cell }{\fs20 1.56E+10\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 10.20\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 103\cell }{\fs20 4.00E+09\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 9.60\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 104\cell }{\fs20 1.29E+10\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 10.11\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 105\cell }{\fs20 7.45E+09\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 9.87\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 106\cell }{\fs20 2.85E+09\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 9.45\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 107\cell }{\fs20 6.91E+09\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 9.83\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 108\cell }{\fs20 2.28E+10\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 10.36\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\trowd \trqc\trgaph29\trrh247\trleft-728\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx335\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx933\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1954\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrr\brdrs\brdrw30 \cltxlrtb \cellx3178\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 109\cell }{\fs20 1.27E+10\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 10.10\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\trowd \trqc\trgaph29\trrh247\trleft-728\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw30 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx335\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx933\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx1954\clvertalt\clbrdrt\brdrs\brdrw15 \clbrdrl\brdrs\brdrw15 \clbrdrb\brdrs\brdrw30 \clbrdrr\brdrs\brdrw15 \cltxlrtb \cellx3178\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 C\cell 110\cell }{\fs20 9.05E+09\cell }\pard \nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20 9.96\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\cf1 \row }\trowd \trqc\trgaph29\trrh247\trleft-728\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\cltxlrtb \cellx-126\clvertalt\cltxlrtb \cellx1913\clvertalt\cltxlrtb \cellx3178\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 \cell }\pard\plain \s5\qr\keepn\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel4\adjustright \b\f1\fs20\cf1\cgrid {Mean\cell }\pard\plain \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid {\b\fs20\cf1 9.98\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\fs18\cf1 \row }\trowd \trqc\trgaph29\trrh247\trleft-728\trbrdrt\brdrs\brdrw30 \trbrdrl\brdrs\brdrw30 \trbrdrb\brdrs\brdrw30 \trbrdrr\brdrs\brdrw30 \trbrdrh\brdrs\brdrw15 \trbrdrv\brdrs\brdrw15 \clvertalt\cltxlrtb \cellx-126\clvertalt\cltxlrtb \cellx1913\clvertalt\cltxlrtb \cellx3178\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\fs20\cf1 \cell }\pard \qr\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\b\fs20\cf1 Standard Deviation\cell }\pard \qc\nowidctlpar\widctlpar\intbl\tx0{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\b\fs20\cf1 0.30\cell }\pard \nowidctlpar\widctlpar\intbl{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright {\f16\fs18\cf1 \row }\pard \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright { \par From the geometric mean of the WetMin values (9.98) we subtract three standard deviations: \par \par \tab 9.98 - 3*(0.30) = 9.08. \par \par Our calculated pass-fail number is 9.05. Since 9.08 > 9.05, our candidate process passes the test, at least numerically. If there is corrosion or metal migration (which bridges more than 20% of the spacing) found on the SIR test pattern after testing, then the test fails. \par \par \par }\pard\plain \s4\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel3\adjustright \b\f1\ul\cgrid {Conclusions \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid { \par As indicated in the overview, J-STD-001B is not a single test, but a series of choices that forces you to look at all the interactions that can occur on your product. Is it more difficult? Yes. Is it costlier? Yes. Should it be done? Yes, in my opinion. In the course of my work, I see process knowledge ranging from exceptional to dangerously ignorant, with the bulk being less than average. Going through the questions posed here and making the choices will force process personnel to closely examine aspects of the process which they have never considered, especially if the work is done elsewhere (contract fabricator or assembler). If nothing else, you gain a much better understanding of the factors which affect the end-item product, which can be of great benefit when troubleshooting a process (which is how I approach it). \par \par Is this the perfect test protocol? By no means. No test method developed by a committee will ever be so. They say that a camel is an elephant designed by a committee. J-STD-001 is a living document, always in flux (no pun intended), and as you read this text, the next revision is being worked upon. If you have suggestions on how to improve the utility of the testing or another approach, please contact me. Since I continue to be involved with the development of the standard, I will make sure that improvements are put forward for discussion. Be advised that I take a dim view of \ldblquote it costs too much\rdblquote . In general, if you want to understand something, you have to invest some time and money. Ever get a Ph.D. for free? \par \par I welcome all comments, inputs, and criticisms (constructive, please). \par \par }\pard\plain \s2\keepn\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\outlinelevel1\adjustright \b\f1\cgrid {Douglas Pauls \par }\pard\plain \s17\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid {Technical Director \par }\pard\plain \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright \f1\cgrid {Contamination Studies Labs \par 201 East Defenbaugh \par Kokomo, IN 46902 \par P: 765-457-8095 \par F: 765-457-9033 \par E: [log in to unmask]\b\ul \page Bibliography}{ \par \par \tab There are a variety of other documents available for the education of the process professional. It is suggested that these reports be reviewed and digested (burp). \par \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls1\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls1\adjustright {EMPF Report RR0013 - \ldblquote An In-Depth Look At Ionic Cleanliness Testing\rdblquote . Contact Toni O\rquote Connor, EMPF, 317-655-3673. This report examines numerous facets of ionic cleanliness testing, and the suitability of these devices as analytical tools for process evaluation. \par }\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl12\ls0\pnrnot0\pndec }\ilvl12\adjustright { \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls1\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls1\adjustright {IPC-TP-1091: The Layman\rquote s Guide to Qualifying a New Flux to MT-0002 and MIL-STD-2000A. This was one of my earlier efforts aimed at MIL-STD-2000A and MT-0002 (same as J-STD-001A). The paper discusses elements of residue characterization. Many of the salient points of that paper apply to J-STD-001B as well. \par }\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl12\ls0\pnrnot0\pndec }\ilvl12\adjustright { \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls1\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls1\adjustright {J-STD-001 Handbook. This document is currently under creation with an expected release date of November 1997. With the move to performance based specifications, much of the how-to information was removed from J-STD-001B. Rather than loose such information, the IPC chartered a task group to capture the information and expand the document into an all inclusive reference work for soldering processes. \par }\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl12\ls0\pnrnot0\pndec }\ilvl12\adjustright { \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls1\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls1\adjustright {IPC-TR-467. This is a technical paper, authored by Jim Maguire, Boeing, and myself. It sets down some of the reasoning behind the way Appendix D was structured the way it was. \par }\pard \nowidctlpar\widctlpar{\*\pn \pnlvlcont\ilvl0\ls0\pnrnot0\pndec }\adjustright { \par {\pntext\pard\plain\f3\cgrid \loch\af3\dbch\af0\hich\f3 \'b7\tab}}\pard \fi-360\li360\nowidctlpar\widctlpar{\*\pn \pnlvlblt\ilvl0\ls1\pnrnot0\pnf3\pnstart1\pnindent360\pnhang{\pntxtb \'b7}}\ls1\adjustright {IPC-9201, The SIR Handbook. Since J1B is primarily SIR driven, a review of this document will increase your understanding of SIR testing. \par }}

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