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residues Electronics Forums search results
1438 results found for residues in 3s.
Showing matching items 1 - 50
- 97%
Flux residue - 7/28/09 -
- ... concern, the solution is to remove the flux residue. Be aware that the residue you see does not represent all of the assembly�s residue. All no-clean processes leave residues behind. The challenge is to determine if the residue to harmless or harmful. Spot removal is not recommended as you are only removing the visible residues. If you have a concern that the residues may be harmful, a defluxing process may be in order. As ironic as it sounds, more of our customers remove no-clean fluxes in ...
- 97%
Flux Designations and Composition - 7/12/04 -
- ... resins and their residues are non-corrosive and non-sticky. They were designed to be left on the board for applications where such residues are acceptable. However there are many occasions in which their residue must be cleaned to comply with their application, such as High Frequency applications etc. See the following comments: ? Flux residue effects on circuit performance? But according to our own experience through a modification for more than 1000 boards, the flux residues remaining after ...
- 97%
White residue after cleaning with IPA - 1/26/03 -
- White residue after cleaning with IPA >But soon after cleaning and drying with IPA, we find a white residue formation. A: IPA will not nothing to clean your board. The white residue is exactly what you should expect. Search the fine SMTnet Archives for background. >How do we avoid this white residue? A: If you want to avoid the white residue, stop using IPA. Your IPA is probably 50% water. Water will turn the residues of most "low residue fluxes" a cloudy, white color. >Is there any other ...
- 95%
Crystalized Flux under BGA - 8/10/04 -
- ... with bare metals, HASL flux residues are generally more active than solder paste residues. Typically a Rosin Active (RA) flux is used in the HASL process. These flux residues should be removed from the bare board. Though with a really thorough examination, some level of HASL flux residue is identifiable on many boards. For NON-SMD pads, the solder mask does not cover up the HASL flux residues which may remain at the base of the pads. Therefore, any HASL residue present around the pad would be ...
- 94%
Flux residue cleaning procedure - 10/31/06 -
- ... soldered well ... OR * Came unsoldered during rework of the nearby BGA ... which is it? Next, the method for cleaning the white residue on the connector will depend on the composition of that material. You say that it is flux. What type of flux do you have on the connector? Finally, whenever we hear "white residue" and "flux" used in the same sentance, we think: "low residue flux and water". Together low residue flux and water cause the flux residue to go milky white. [Hint: IPA is 50% water ...
- 94%
voids in solder - 3/6/01 -
- ... Strategy for A Low-Residue No-Clean Process - Provides direction to electronics manufacturers interested in adopting low residue (LR) assembly technology. It addresses the concerns of process engineers and others coming into the field of low-residue processes from two different areas: those who currently clean finished assemblies using water-based, semi-aqueous or other environmentally acceptable solvents and defluxing technologies; or those who use a standard residue-level (SR) no-clean ...
- 93%
Flux residue - 7/28/09 -
- Flux residue Hi All, I have some question about flux residue resulted from non clean process as following: 1) Under what kind of circumstances that flux residue could appear? This residue does not happen during production but did appear after some period of time leaving factory. 2) How to clean this type of flux residue? 3) Is there any potentially that our wave machine parameter setting not optimized that could cause this flux residue appearance? If yes, which wave machine parameter setting ...
- 93%
Flux residue on connector pins - 8/29/04 -
- Flux residue on connector pins Chen, It is always best to place one?s effort on determining the cause and content of the residue rather than trying to work around it. The first thing you must determine is the nature of the residue. Is it flux? In many instances, the residue is not flux. There are many things it may be besides flux (metal salts, minerals, chemical residue, etc). If it is flux, and the flux is soluble in water (OA), then why is it still on the connector? Questions to consider: 1 ...
- 93%
Flux residual on joints of PIH - 4/27/05 -
- Flux residual on joints of PIH Hi Sarag, We share Sara's described experience with cleaning No-Clean/Low Residue flux residues. We can add that of the Low Residue residues, Indium SMQ92J is one of the more challenging flux residues to clean. That said, we have had repeated success with this cleaning process. Should you decide to consider cleaning as a standard process or for the batch of boards produced so far, we would be happy to speak with you about our experiences and try to help you with ...
- 93%
White Residues - 8/17/05 -
- White Residues Dave, Answers to your questions: * From your pictures, the white residue appears to be only on the solder mask. Is that correct? If not, what is the location [eg, solder, nonsolder/nonmask areas] of the residue that doesn't show well in the pictures? Further, is this strictly a second-side problem? The areas with noticeable white residues were on solder side, solder mask only, and around all T/H leads. * You say that the white residue appears after washing, what temperature were ...
- 92%
White Residue / Vapor Degrease - 1/14/99 -
- White Residue / Vapor Degrease I get white residue on my PCBs after vapor degreasing. No comments on the vapor degreaser. Yes, I still use one of these. I use a vapor degreaser and a 1,1,1 replacement solvent due to the quick clean and quick dry times. Anyway, I only get white residues with certain NC solder pastes. Some other NC solders do not produce this white residue. You might wonder, why do I bother to clean at all if I am using NC paste. Well, we manufacture medical devices with lots of ...
- 91%
Flux residual on joints of PIH - 4/27/05 -
- Flux residual on joints of PIH Have you examined what type of residue is present? It is possible that what you are seeing is benign, though flux that is not fully activated often leaves harmful residue species such as chloride or weak organic acids. If you don't want to change pastes, you could look at modifying your profile to make sure the flux residues are fully heat activated, or you could even look at cleaning these residues if they are harmful or don't pass your visual criterion. No clean ...
- 91%
Flux residue - 7/31/09 -
- Flux residue Dear Sean Contrary to believe MOST formulators of No Clean fluxes or No Residue fluxes use organic acides that are in fact weak and benign. IF the residue was left on the board and you had a condensing atmosphere then you may see some issue with falling SIR values, but generally not electromigration. UNLESS the resiue left was a Halide containing residue (not No Clean) then you may see electromigration or much poorer SIR values. So the residue appears some time after. Is the PCB ...
- 91%
White Residues - 8/16/05 -
- White Residues Peter: Questions are: * From your pictures, the white residue appears to be only on the solder mask. Is that correct? If not, what is the location [eg, solder, nonsolder/nonmask areas] of the residue that doesn't show well in the pictures? Further, is this strictly a second-side problem? * You say that the white residue appears after washing, what temperature were the boards when washed? What was the wash temperature? * You say that the white residue appears after washing, what ...
- 91%
no-clean flux removal - 1/20/05 -
- ... to a previous thread promoting ?no-residue? fluxes, I must say that there is absolutely no such thing as ?No-Residue? flux. There are ?Low-Residue? fluxes and even ?Very-Low? residue fluxes but to suggest that there is absolutely no residue is not accurate. I manufacture cleaning systems so naturally I would like to see everyone clean their boards, but the facts are that not every application requires cleaning. In many cases the amount of residue left on the board is acceptable for that specific ...
- 91%
White residue VS No clean - 7/28/01 -
- White residue VS No clean Hi all I just got feedback from my customer about "White residue problem" around solder joints with manaul soldered connector at customer site and included the failure analysis report that there is residues of Cl,S,Na . I 'd like to know, the white residue/comtammination come from? and Are they(white residue and Cl,S,Na) rejected under IPC standard? Thank you and best regard ...
- 91%
CSP No clean residue - 12/13/04 -
- CSP No clean residue Hi Scott - No clean assemblies have a very low tolerance for processing residues, and long term reliability is compromised if residues from incoming bare boards, components, or un-solublized flux residues are not dealt with. It is critical to control these aspects of cleanliness since a no clean process is not meant to go through cleaning, and cleaning is very difficult if a residue is discovered after assembly. To see some studies on this topic, visit our website at
- 91%
White residue after cleaning with IPA - 2/3/03 -
- White residue after cleaning with IPA White residues are a common problem when cleaning no-clean fluxe residues. The white residue forms when the flux residue is partialy removed, etc. Alcohol should not be your only solution for cleaning. In general, solvents may attack some plastic parts and inks so I prefer a water based chemistry for cleaning. I personally use Kyzen A4406E at 120 degrees F. in a spray washer (modified AAT) and it cleans great. This chemistry has mild saponification and does ...
- 91%
Stainless Steel in wash system - 9/20/01 -
- ... residue. It can attack the finish of electro-polished (mirrored) stainless steel though. I have seen a white / chalky buildup on poly inline cleaners, usually isolated in the wash section. The rinse and final rinse sections (with the best water quality) normally do not build up this residue. If the residue is mainly in the wash section (the dirtiest and less de-ionized of all of the cleaner?s water) it is most likely a result of a buildup of organic ?stuff? that is capable of leaving a residue ...
- 91%
Re: white residue - 2/10/99 -
- ... i am working with the noclean process and getting white residues on the bottomside of the board probably due to the | | | | wave soldering flux.i am using a no-clean solder paste and a noclean wave solder flux.The boards passed the accelerated temperature and humidity tesing. Can i consider the residue as non-ionic. will it affect the assembly reliability?if so how?is there a standard in industry on the acceptable white residue for a no-clean process?please throw light on the problem ...
- 91%
Whitish Solder Joint - 4/4/03 -
- ... appearance of this white residue? [eg, glassy / coarse, milky colored / opaque, thin / thick film, hard / soft, color white, etc] * Where are these white residues located? [eg, pads only, solder mask only, every where, etc.] * What is the scope and extent of the problem? * What is your process, process materials, board fabrication, and process settings? Q2: Why do some white residues pass ionic contamination tests and other white residues do not pass? A2: White residues are chemical compounds ...
- 90%
White residues - 5/25/08 -
- ... is that there was no white residues formed on wave solder or hand solder joints. So those white residues should be a chemical interaction between the flux in the solder paste, detergent and DI water. We have changed and tried the solder paste from Multicore, Alpha and Qualitek, the residue concentration has changed, lesser with Qualitek may be but still there. I will be appreciated any comments that you can send me for helping me to get rid of those white residues and find a solution to have ...
- 90%
White Residues - 8/16/05 -
- White Residues Hello, I have a question on white residues formation at wave soldering. We have recently run experiments to test the performance of various halide-free water soluble fluxes (ORH0 under JSTD-004). The flux was applied through a spray fluxer and all PCAs were immediately washed after wave soldering in in-line cleaner, with DI water only. Surprisingly, we've identified several PCAs built with flux A from one vendor exhibiting white residues at various T/H leads on the boards. See ...
- 90%
Flux residual on joints of PIH - 4/27/05 -
- Flux residual on joints of PIH You will probably need to change paste. If I remember correctly the SMQ92J has a post reflow residue of 40%. This is one of the highest post reflow residue levels available. PIH uses a lot of paste which means a lot of flux residue. There are other Mfgr that have less residue. Alpha om5100 is one example. Russ
- 90%
White residues - 4/29/02 -
- White residues I had problems with white residues on both WS609 and WS 3060.The WS 3060 turned out to be a carbonized material.The composition after analysis (Energy Dispersive X-ray spectrum) turned out to be tin,tin,phosphore and cloline and tin. Alpha also have a technical paper on their website called White residue and water soluble fluxes:Removal of No-Clean flux residue - 9/6/01 -
- Removal of No-Clean flux residue We're with Kevin. First, there is hardly a worse cleaning solvent for fluxes than IPA. At the best, it will spread the soluble residue over a larger area, until it is thin enough to be invisible. This increases the surface area so that any dangerous contaminants, such as those ionic compounds that are soluble in IPA are more readily accessible to cause harm. Next, IPA is VERY poor at dissolving the metal-organic salts formed by reaction between the flux and the ...
- 90%
Re: When using noclean flux or clean flux process? - 9/22/99 -
- ... board. This creates several potential problems: | | ? In some applications, like high frequncy, the no-clean flux residues can interact with circuit functions. | ? No-clean flux residues can interfer with automatic test probes. | ? Some people don't like the appearance of flux residues. | ? Conformal coating of boards with no-clean residues requires more care. | | Further, no-clean fluxes have a narrower soldering process window than washable fluxes, increasing the cost of soldering and material ...
- 90%
Re: baked on water soluble flux residue betwwen fine pitch comp. - 12/1/00 -
- ... on water soluble flux residue betwwen fine pitch comp. Curious, very curious ... Residues ? Where are these residues? [solder & laminate / mask, solder only, laminate / mask only] What is the result of your analysis to the residues? How do you know it?s a flux residue, rather than a chemical by product of the flux and metal oxides? Why isn?t this residue forming during the soldering process when the temperatures are presumably higher? Or could it be: the residues are forming during soldering and ...
- 90%
PCB post reflow cleaning - 3/26/04 -
- PCB post reflow cleaning Patrick, When you say "no-residue" what exactly do you mean? Is there truely "no-residue" or is it "no visible residue"? What type of ionic contamination results have you experienced? If you take a bare board that measures 0.0 NaCl and reflow it with the "no-residue" paste, will it still measure a 0.0? Have SIR and Ion Chromatography tests confirmed that there is NO residue? I would be interested to know the results of your test data. Thanks, Mike Konrad Aqueous ...
- 90%
Cleaning no-clean residue - 4/17/01 -
- Cleaning no-clean residue I have struggled with this myself. Usually where the pressure to clean the residue off is from the people who see the residue but do not understand the characteristics. I have not found a reason to clean residue off. A few people from our design group hold the stance that the residue is bad, but we have yet to prove it. Resist the pressure to clean the boards until you have good data. Opinions don't prove anything ...
- 90%
Re: White Residue / Vapor Degrease - 1/20/99 -
- Re: White Residue / Vapor Degrease | I get white residue on my PCBs after vapor degreasing. No comments on the vapor degreaser. Yes, I still use one of these. I use a vapor degreaser and a 1,1,1 replacement solvent due to the quick clean and quick dry times. Anyway, I only get white residues with certain NC solder pastes. Some other NC solders do not produce this white residue. | | You might wonder, why do I bother to clean at all if I am using NC paste. Well, we manufacture medical devices with ...
- 89%
Re: white residue after wash - 4/5/98 -
- ... that the alcohol was actually doing a better cleaning job....but there were occasional "white residues". Modern process chemistries may be similarly affected or may exhibit OTHER forms of white residue... the essential message being: DO Not clean No-Clean! There is no such thing as no residue flux - there is fluxless soldering, but that is another technology. Thus, if you leave residues, they WILL react unpredicatbly maybe, with different types of cleaning chemistry - alcohol, methanol ...
- 89%
Re: white residue - 1/29/99 -
- ... i am working with the noclean process and getting white residues on the bottomside of the board probably due to the | | | wave soldering flux.i am using a no-clean solder paste and a noclean wave solder flux.The boards passed the accelerated temperature and humidity tesing. Can i consider the residue as non-ionic. will it affect the assembly reliability?if so how?is there a standard in industry on the acceptable white residue for a no-clean process?please throw light on the problem ...
- 89%
Re: white residue - 1/27/99 -
- Re: white residue | | i am working with the noclean process and getting white residues on the bottomside of the board probably due to the | | wave soldering flux.i am using a no-clean solder paste and a noclean wave solder flux.The boards passed the accelerated temperature and humidity tesing. Can i consider the residue as non-ionic. will it affect the assembly reliability?if so how?is there a standard in industry on the acceptable white residue for a no-clean process?please throw light on the ...
- 89%
Cleaning no-clean residue - 4/17/01 -
- Cleaning no-clean residue Continuing with Steve's comments, the true measure of whether or not residues [NC or not] are good or bad is found in the results of an laboratory analysis of the residues and an assessment of the impact of that level of residue ...
- 89%
Wire bonding on gold fingers - 7/1/03 -
- ... assembly. Everything leaves a residue, and trying to clean a residue off later is basically hopeless. This may require some trickery in your SMT process, so that you can print solder over the glob-topped IC or whatever you're wirebonding. If this is very difficult, and the economics permit, you can use syringe solder dispense instead of stencil printing. If it's really not possible to reconfigure your process in this way, your best bet is to clean any residue with plasma etching. This is not ...
- 89%
baked on water soluble flux residue betwwen fine pitch comp. - 12/1/00 -
- baked on water soluble flux residue betwwen fine pitch comp. My company currently uses water soluble paste for our SMT process. We were having trouble retaining hot water in our in line, closed loop DI cleaner. The cleaner kept shutting down when the water temp. dropped below 125C. As a result, the conveyor shut down and the boards stayed in the hot area of the cleaner consequently any flux residue has been baked on the board.I've recreated this scenario with great success during my experiments ...
- 89%
ionic residues on the surface of printed circuit assemblies - 9/2/09 -
- ionic residues on the surface of printed circuit assemblies You can determine empirically what will work. * Use ion chromatography [IPC-TM-650 2.3.28] to evaluate the residues and determine if the residues must be removed. * Use energy dispersive spectroscopy for the elemental analysis or chemical characterization of the residue ...
- 89%
White residues - 4/22/02 -
- White residues Hi, this is not really a technical solution, just a feedback. we too have a model series using the same WS paste type. it gives a dull solder joint with white residue that can be marginally removed after post-DI water rinse (ie. not 100% removed). We flipped thru our IPC-A-610C and reversed analysis our process flow for the product. till today we can't eliminate 100% the occurrence of white residue on solder joints, nor improve the solder joints into "target" IPC specs of bright ...
- 89%
Residue - 5/26/98 -
- Residue We recently made the switch to no-clean and the wurface mount is turning out beautifully. However, the wave solder process continues to put up a fight; we are getting a white residue on the surface of the PCB. The residue is not localized to just the solder joints, but is similar to water spots on a car, it is on the PCB surface. We have played with the preheat temperatures and flux volume. But the flux volume cannot change too much as we are not getting very many solder problems (i.e ...
- 89%
white residue - 1/27/99 -
- white residue i am working with the noclean process and getting white residues on the bottomside of the board probably due to the wave soldering flux.i am using a no-clean solder paste and a noclean wave solder flux.The boards passed the accelerated temperature and humidity tesing. Can i consider the residue as non-ionic. will it affect the assembly reliability?if so how?is there a standard in industry on the acceptable white residue for a no-clean process?please throw light on the problem
- 89%
Re: When using noclean flux or clean flux process? - 9/21/99 -
- ... This creates several potential problems: ? In some applications, like high frequncy, the no-clean flux residues can interact with circuit functions. ? No-clean flux residues can interfer with automatic test probes. ? Some people don't like the appearance of flux residues. ? Conformal coating of boards with no-clean residues requires more care. Further, no-clean fluxes have a narrower soldering process window than washable fluxes, increasing the cost of soldering and material control. Continuing ...
- 89%
Cleanning no clean residu - 10/19/07 -
- ... A no-clean process leaves some degree of ionic residue. That is a fact. Eliminating ionic residues will make your board (and application) no reliable. Cleaning either reduces or eliminates ionic and other forms of contamination. The big question is whether your specific application will be negatively effected by the level of ionic contamination left behind on the board. While is true that many applications are not negatively effected by residual contamination, it is likewise true that all high ...
- 89%
Flux Residues In Lead Free Wave Soldering Process - 3/28/06 -
- Flux Residues In Lead Free Wave Soldering Process Thanks for the input Guys Yeah the not so knowledgable customer does not like to residues for cosmetic resons. The flux is for lead free process, of the no clean and water soluable type. We have explained to him that technically the residues do not post a problem since it has no impact on the SIR etc. We even provided him with a white paper on the white residue issue. Stil ?%*(&/&(//( My test guys of course do not like me either but understand ...
- 89%
Re: Residue - 5/26/98 -
- ... to put up a fight; we are getting a white residue on the surface of the PCB. The residue is not localized to just the solder joints, but is similar to water spots on a car, it is on the PCB surface. We have played with the preheat temperatures and flux volume. But the flux volume cannot change too much as we are not getting very many solder problems (i.e. bridging, opens, etc.) Any ideas how to get rid of this residue. I realize some residue is expected, but the literature says the flux leaves ...
- 88%
Re: white residue - 1/28/99 -
- Re: white residue | | i am working with the noclean process and getting white residues on the bottomside of the board probably due to the | | wave soldering flux.i am using a no-clean solder paste and a noclean wave solder flux.The boards passed the accelerated temperature and humidity tesing. Can i consider the residue as non-ionic. will it affect the assembly reliability?if so how?is there a standard in industry on the acceptable white residue for a no-clean process?please throw light on the ...
- 88%
Re: white residue - 1/27/99 -
- Re: white residue | i am working with the noclean process and getting white residues on the bottomside of the board probably due to the | wave soldering flux.i am using a no-clean solder paste and a noclean wave solder flux.The boards passed the accelerated temperature and humidity tesing. Can i consider the residue as non-ionic. will it affect the assembly reliability?if so how?is there a standard in industry on the acceptable white residue for a no-clean process?please throw light on the ...
- 88%
Re: More informations on water clean for CSP/BGA package - 10/8/99 -
- ... boards, we see some white residue on these component joints even though it pass our ionic test. | | | | | | Any comment on whether could we establish some form of guideline? | | | Thank you, | | | | | | rgs | | | karlin | | | | | Karlin: So, what is this white residue? Is it soluable in water? Ta. Dave F | | Hi Dave, | | The white residue is soluable in water and we has confirmed that it is our flux residues from the EDX lab analysis. | | karlin | | If the residues are water soluble, this is all ...
- 88%
Re: Tape residue cleaner - 4/7/00 -
- Re: Tape residue cleaner Ashok: You should select and use low residue tapes. But ya know, ya go out and research a great tape and if yer not careful, the buyer will second source ya and (surprise) ya got residues again. We have found that Lemme say this about Katon tapes: ? They?re expensive, which has a big piece to do with why buyers (and bean counters) are always angling to find a cheaper alternative. ? Everyone who can spell "tape" makes a Kapton tape. ? Lots of the high-temp Kapton-type ...
- 88%
Reduce flux - 1/18/07 -
- ... solder paste: Different no-clean solder pastes will leave different types of (benign) residues. If your paste has been qualified from a Bellcore/SIR/Electromigration standpoint, any residues remaining will NOT ever cause problems in the field...EVER! Some typical areas that flux residues pool up: 1.) Around chip components. 2.) Around fine pitch IC Leads.. 3.) The DPAK Heatsink area... etc.. Flux residues will also look... 1.) brown and gummy. 2.) flakey 3.) or gummy transparent.. Again it ...
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