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Cleaning procedures for Entek-Plus Cu-106A

Stephen Smith

#11864

Cleaning procedures for Entek-Plus Cu-106A | 20 April, 1999

I am wondering if anyone has any info regarding solder paste misprint clean-up procedures for Entek Plus CU-106A PCB's utilizing a water-clean solder paste. In a implementation procedure they recommend a 2-3 minute wash cycle with the following criteria: a) Temperature of 140�F or below b) pH of water above 5.0 c) Spray pressure of 40 psi or below and d) Forced hot air drying. We satisfy all of the requirements except for the spray pressure, which currently is 90 psi at the rinse section of the machine. I am wondering what effect if any that will have on the Entek Plus coated boards. Does the higher pressure remove some of the organic coating? We don't have the liberty of changing our pressure with out putting in a different nozzle, which if at a lower pressure could have an impact on the effectiveness of cleaning in general as well as lower profile components. I'd like to use solder samples to tweak our printing process if needed but because we are a C/M our customers don't always provide us with one. I'd like to know how Companies are approaching this particular problem?

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Justin Medernach

#11865

Re: Cleaning procedures for Entek-Plus Cu-106A | 20 April, 1999

| I am wondering if anyone has any info regarding solder paste misprint clean-up procedures for Entek Plus CU-106A PCB's utilizing a water-clean solder paste. In a implementation procedure they recommend a 2-3 minute wash cycle with the following criteria: a) Temperature of 140�F or below b) pH of water above 5.0 c) Spray pressure of 40 psi or below and d) Forced hot air drying. We satisfy all of the requirements except for the spray pressure, which currently is 90 psi at the rinse section of the machine. I am wondering what effect if any that will have on the Entek Plus coated boards. Does the higher pressure remove some of the organic coating? We don't have the liberty of changing our pressure with out putting in a different nozzle, which if at a lower pressure could have an impact on the effectiveness of cleaning in general as well as lower profile components. I'd like to use solder samples to tweak our printing process if needed but because we are a C/M our customers don't always provide us with one. I'd like to know how Companies are approaching this particular problem? | Everything removes Entek Plus. That's not entirely true but pretty darn close. Alcohol rips it off. Most solvents do too. Heat certainly does. I don't know what kind of detergent you use in your cleaner but I would bet that pulls off the coating as well. Although they'll deny, if you push them on taking measurements of coating thickness before and after wash, you'll find a difference. If you clean the board and then process soon after, you'll still have an adequate yield. I noticed no difference in yield when we cleaned misprints with alcohol. Everything was good as long as we processed the board within an hour of wiping down.

Hope this helps. Regards, Justin

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#11866

Re: Cleaning procedures for Entek-Plus Cu-106A | 20 April, 1999

| | I am wondering if anyone has any info regarding solder paste misprint clean-up procedures for Entek Plus CU-106A PCB's utilizing a water-clean solder paste. In a implementation procedure they recommend a 2-3 minute wash cycle with the following criteria: a) Temperature of 140�F or below b) pH of water above 5.0 c) Spray pressure of 40 psi or below and d) Forced hot air drying. We satisfy all of the requirements except for the spray pressure, which currently is 90 psi at the rinse section of the machine. I am wondering what effect if any that will have on the Entek Plus coated boards. Does the higher pressure remove some of the organic coating? We don't have the liberty of changing our pressure with out putting in a different nozzle, which if at a lower pressure could have an impact on the effectiveness of cleaning in general as well as lower profile components. I'd like to use solder samples to tweak our printing process if needed but because we are a C/M our customers don't always provide us with one. I'd like to know how Companies are approaching this particular problem? | | | Everything removes Entek Plus. That's not entirely true but pretty darn close. Alcohol rips it off. Most solvents do too. Heat certainly does. I don't know what kind of detergent you use in your cleaner but I would bet that pulls off the coating as well. Although they'll deny, if you push them on taking measurements of coating thickness before and after wash, you'll find a difference. If you clean the board and then process soon after, you'll still have an adequate yield. I noticed no difference in yield when we cleaned misprints with alcohol. Everything was good as long as we processed the board within an hour of wiping down. | | Hope this helps. | Regards, | Justin | My notes on Entek tell me that alcohol takes away 70% of the coating, water takes 15%, and Kyzen Lonox only takes about 3%. Yes, just about everything removes Entek, especially if there's heat involved.

Enthone recommends that if you wash the board "thoroughly" (alcohol or solvent), strip the coating and expose copper, you complete all soldering operations within 12 hours.

Got these figures from notes I took at a tech session at Nepcon. An Enthone guy was doing the talking, so the numbers should be fairly reliable.

Chrys

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Earl Moon

#11867

Re: Cleaning procedures for Entek-Plus Cu-106A | 20 April, 1999

| | I am wondering if anyone has any info regarding solder paste misprint clean-up procedures for Entek Plus CU-106A PCB's utilizing a water-clean solder paste. In a implementation procedure they recommend a 2-3 minute wash cycle with the following criteria: a) Temperature of 140�F or below b) pH of water above 5.0 c) Spray pressure of 40 psi or below and d) Forced hot air drying. We satisfy all of the requirements except for the spray pressure, which currently is 90 psi at the rinse section of the machine. I am wondering what effect if any that will have on the Entek Plus coated boards. Does the higher pressure remove some of the organic coating? We don't have the liberty of changing our pressure with out putting in a different nozzle, which if at a lower pressure could have an impact on the effectiveness of cleaning in general as well as lower profile components. I'd like to use solder samples to tweak our printing process if needed but because we are a C/M our customers don't always provide us with one. I'd like to know how Companies are approaching this particular problem? | | | Everything removes Entek Plus. That's not entirely true but pretty darn close. Alcohol rips it off. Most solvents do too. Heat certainly does. I don't know what kind of detergent you use in your cleaner but I would bet that pulls off the coating as well. Although they'll deny, if you push them on taking measurements of coating thickness before and after wash, you'll find a difference. If you clean the board and then process soon after, you'll still have an adequate yield. I noticed no difference in yield when we cleaned misprints with alcohol. Everything was good as long as we processed the board within an hour of wiping down. | | Hope this helps. | Regards, | Justin | Justin is absolutely right. When cleaning misprints or whatever, you remove all or part of the organic coating (OCC/OSP). If you don't get it all, you will have gotten enough to render the stuff useless in a short time.

Again, Entek is not much more than a flux coating designed to temporarily protect the copper surface beneath it from oxidizing. Scratch a penny, if anyone has access to them anymore besides the local 7/11, and watch it oxidize.

Metallic coatings protect best, as we all know - especially those electroplated. Those coatings chemical come in next to no coating at all under the right/wrong conditions.

Time is a critical factor when dealing with organics. Diminishing their effectiveness (time, temperature, water, pressure, etc.), lessens their ability to protect solder termination area solderability effectiveness.

Earl Moon

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#11868

Re: Cleaning procedures for Entek-Plus Cu-106A | 21 April, 1999

Earl said, in essence:

| Justin is absolutely right ... | | Again, Entek is not much more than a flux coating ... | | Metallic coatings protect best, as we all know - especially those electroplated. Those coatings chemical come in next to no coating at all under the right/wrong conditions. | Moonbert: Welcome back, it seems like you never left.

We know of your history of being HASL-retentive. So, how do white tin protectants (Omicron & Dexter) fit in your schemes of electroplated metal superiority? The other day, I saw some really neat SEM pictures pointing-out the simlarities between the intermetallics of HASL and Dexter's "what ever they call it."

TTYL

Dave F

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Earl Moon

#11869

Re: Cleaning procedures for Entek-Plus Cu-106A | 25 April, 1999

| Earl said, in essence: | | | Justin is absolutely right ... | | | | Again, Entek is not much more than a flux coating ... | | | | Metallic coatings protect best, as we all know - especially those electroplated. Those coatings chemical come in next to no coating at all under the right/wrong conditions. | | | | Moonbert: Welcome back, it seems like you never left. | | We know of your history of being HASL-retentive. So, how do white tin protectants (Omicron & Dexter) fit in your schemes of electroplated metal superiority? The other day, I saw some really neat SEM pictures pointing-out the simlarities between the intermetallics of HASL and Dexter's "what ever they call it." | | TTYL | | Dave F | Moonbert? Never been called that before. Coming from you Dave, I don't give a damn, but then I really don't give a damn anyway.

White tin is tin. Tin oxidizes readily. How readily? I don't know and I'm not prepared to find the answer.

We're transitioning to OCC/OSP on some of our 1500 assemblies. We use gold on R/F and it often works. We use HASL - Uhg! Hell you cited my feelings about this stuff, but I must tell you how our Fuji's hate it now. Another reason to dump the stuff as its fiducial topography isn't easily recognizable to any known camer system.

Do you have any information about the white stuff?

Earlbert

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#11870

Re: Cleaning procedures for Entek-Plus Cu-106A | 26 April, 1999

| | Earl said, in essence: | | | | | Justin is absolutely right ... | | | | | | Again, Entek is not much more than a flux coating ... | | | | | | Metallic coatings protect best, as we all know - especially those electroplated. Those coatings chemical come in next to no coating at all under the right/wrong conditions. | | | | | | | Moonbert: Welcome back, it seems like you never left. | | | | We know of your history of being HASL-retentive. So, how do white tin protectants (Omicron & Dexter) fit in your schemes of electroplated metal superiority? The other day, I saw some really neat SEM pictures pointing-out the simlarities between the intermetallics of HASL and Dexter's "what ever they call it." | | | | TTYL | | | | Dave F | | | Moonbert? Never been called that before. Coming from you Dave, I don't give a damn, but then I really don't give a damn anyway. | | White tin is tin. Tin oxidizes readily. How readily? I don't know and I'm not prepared to find the answer. | | We're transitioning to OCC/OSP on some of our 1500 assemblies. We use gold on R/F and it often works. We use HASL - Uhg! Hell you cited my feelings about this stuff, but I must tell you how our Fuji's hate it now. Another reason to dump the stuff as its fiducial topography isn't easily recognizable to any known camer system. | | Do you have any information about the white stuff? | | Earlbert | Earl: The nice parts about OCC/OSP are it�s flat and it�s cheap. We're just kickin tires on white tin.

A 5000X SEM of immersion tin plating (like on the end-caps of the million or so ceramic caps each of us have put down in the last couple years) shows this crystal structure, lots of flat, irregular, pointy grains. And it�s from the points that the dreaded tin whiskers grow (or is it the dread yellow snow from where the huskies go?) This stuff is gray tin. White tin has a completely different grain structure, which looks like polygons under SEM � less likely to whisker??? SEMs of solder connections show similar imtermetalics between HASL and white tin.

Compared to HASL:

OSP

1 Drop in replacement for HASL at assembly - NO 1a Fluxes (SMT and wave) - NO 1b Reflow processing (Air, N2 profile) - NO 1c Storage handling - NO 1d In circuit test - NO 2 Have at least a 6 month shelf life - YES 3 Cost the same or less than HASL - YES 4 Provide flat/planar pads - YES 5 Be compatible with complaint pin technology - YES 6 Meet Bellcore and reliability criteria - YES 7 Be compatible with existing fab process - YES 8 Be readily available - YES

ENIG

1 Drop in replacement for HASL at assembly - MARGINAL 1a Fluxes (SMT and wave) - YES 1b Reflow processing (Air, N2 profile) - YES 1c Storage handling - MARGINAL 1d In circuit test - YES 2 Have at least a 6 month shelf life - YES 3 Cost the same or less than HASL - NO 4 Provide flat/planar pads - YES 5 Be compatible with complaint pin technology - NO 6 Meet Bellcore and reliability criteria - NO?? 7 Be compatible with existing fab process - YES 8 Be readily available - YES

White Tin

1 Drop in replacement for HASL at assembly - YES 1a Fluxes (SMT and wave) - YES 1b Reflow processing (Air, N2 profile) - YES 1c Storage handling - YES 1d In circuit test - YES 2 Have at least a 6 month shelf life - YES 3 Cost the same or less than HASL - YES 4 Provide flat/planar pads - YES 5 Be compatible with complaint pin technology - YES 6 Meet Bellcore and reliability criteria - YES 7 Be compatible with existing fab process - YES 8 Be readily available - NO

That otta get the nitpickers out there going ...

This was pulled from a "Future Circuits International" (whatever that is ... ) article. Call:

Florida CirTech (800) 686-6504 Mike Scimeca (President) Stephen Wentz hihat44@aol.com Dexter Industry CA 626.968.6511 fax 336.0160

Bottom line: White tin costs about the same as HASL. So even with the assembly process limitations of OSP, low material cost is a powerful driver for wide-spread acceptance in all applications, not just those requiring planar pads. Leading to volume driving down costs, providing resources for product/process improvement bla-bla-bla

So Earl, have you gone honest and haken a real job or is this a consulting project?

TTYL

Davebert

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Earl Moon

#11871

Re: Cleaning procedures for Entek-Plus Cu-106A | 26 April, 1999

| | | Earl said, in essence: | | | | | | | Justin is absolutely right ... | | | | | | | | Again, Entek is not much more than a flux coating ... | | | | | | | | Metallic coatings protect best, as we all know - especially those electroplated. Those coatings chemical come in next to no coating at all under the right/wrong conditions. | | | | | | | | | | Moonbert: Welcome back, it seems like you never left. | | | | | | We know of your history of being HASL-retentive. So, how do white tin protectants (Omicron & Dexter) fit in your schemes of electroplated metal superiority? The other day, I saw some really neat SEM pictures pointing-out the simlarities between the intermetallics of HASL and Dexter's "what ever they call it." | | | | | | TTYL | | | | | | Dave F | | | | | Moonbert? Never been called that before. Coming from you Dave, I don't give a damn, but then I really don't give a damn anyway. | | | | White tin is tin. Tin oxidizes readily. How readily? I don't know and I'm not prepared to find the answer. | | | | We're transitioning to OCC/OSP on some of our 1500 assemblies. We use gold on R/F and it often works. We use HASL - Uhg! Hell you cited my feelings about this stuff, but I must tell you how our Fuji's hate it now. Another reason to dump the stuff as its fiducial topography isn't easily recognizable to any known camer system. | | | | Do you have any information about the white stuff? | | | | Earlbert | | | Earl: The nice parts about OCC/OSP are it�s flat and it�s cheap. We're just kickin tires on white tin. | | A 5000X SEM of immersion tin plating (like on the end-caps of the million or so ceramic caps each of us have put down in the last couple years) shows this crystal structure, lots of flat, irregular, pointy grains. And it�s from the points that the dreaded tin whiskers grow (or is it the dread yellow snow from where the huskies go?) This stuff is gray tin. White tin has a completely different grain structure, which looks like polygons under SEM � less likely to whisker??? SEMs of solder connections show similar imtermetalics between HASL and white tin. | | Compared to HASL: | | OSP | | 1 Drop in replacement for HASL at assembly - NO | 1a Fluxes (SMT and wave) - NO | 1b Reflow processing (Air, N2 profile) - NO | 1c Storage handling - NO | 1d In circuit test - NO | 2 Have at least a 6 month shelf life - YES | 3 Cost the same or less than HASL - YES | 4 Provide flat/planar pads - YES | 5 Be compatible with complaint pin technology - YES | 6 Meet Bellcore and reliability criteria - YES | 7 Be compatible with existing fab process - YES | 8 Be readily available - YES | | ENIG | | 1 Drop in replacement for HASL at assembly - MARGINAL | 1a Fluxes (SMT and wave) - YES | 1b Reflow processing (Air, N2 profile) - YES | 1c Storage handling - MARGINAL | 1d In circuit test - YES | 2 Have at least a 6 month shelf life - YES | 3 Cost the same or less than HASL - NO | 4 Provide flat/planar pads - YES | 5 Be compatible with complaint pin technology - NO | 6 Meet Bellcore and reliability criteria - NO?? | 7 Be compatible with existing fab process - YES | 8 Be readily available - YES | | White Tin | | 1 Drop in replacement for HASL at assembly - YES | 1a Fluxes (SMT and wave) - YES | 1b Reflow processing (Air, N2 profile) - YES | 1c Storage handling - YES | 1d In circuit test - YES | 2 Have at least a 6 month shelf life - YES | 3 Cost the same or less than HASL - YES | 4 Provide flat/planar pads - YES | 5 Be compatible with complaint pin technology - YES | 6 Meet Bellcore and reliability criteria - YES | 7 Be compatible with existing fab process - YES | 8 Be readily available - NO | | That otta get the nitpickers out there going ... | | This was pulled from a "Future Circuits International" (whatever that is ... ) article. Call: | | Florida CirTech (800) 686-6504 Mike Scimeca (President) Stephen Wentz hihat44@aol.com | Dexter Industry CA 626.968.6511 fax 336.0160 | | Bottom line: White tin costs about the same as HASL. So even with the assembly process limitations of OSP, low material cost is a powerful driver for wide-spread acceptance in all applications, not just those requiring planar pads. Leading to volume driving down costs, providing resources for product/process improvement bla-bla-bla | | So Earl, have you gone honest and haken a real job or is this a consulting project? | | TTYL | | Davebert | | DamnDaveBert,

I know you didn't mean to insult such a sensitive one as me, but putting honesty and real together in the same sentence is pushing it. Actually, I'm doing "real" & "honest" work toegether under a contract.

I know that too is a stretch, but you know how I can be. To put it honestly, if at all possible, I'm being overpaid to learn from some of the best while under the guise of teaching the stuff.

Now you all know I am limited, both in brain power and being capable of all I forgot, but don't count me out. I have never had a happier experience while constantly reminding my peers there's no reason to get frustrated while collecting a respectable pay check.

Just a note, if I've not already done so, my key responsibilities include stencil printing and all that goes with it and rework as a direct reflection of how I screwed up - up front. How's that in light of the fact one of my operators said we don't need no stinking procedures or check lists because we have six month's experience. This is from the mouth of a great looking lady who ran a batch of boards all the way through the BTU - UP F'N SIDE DOWN.

Boogie and dont forget the tighter the crystalline structure - the less oxidation - but tin oxidizes readily. The question is how much and under circumstances, how quickly.

MoonManBert

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#11872

Re: Cleaning procedures for Entek-Plus Cu-106A | 26 April, 1999

Dave said:

| | So Earl, have you gone honest and haken a real job or is this a consulting project? | | | | TTYL | | | | Davebert | | | | | DamnDaveBert, | | I know you didn't mean to insult such a sensitive one as me, but putting honesty and real together in the same sentence is pushing it. Actually, I'm doing "real" & "honest" work toegether under a contract. | | I know that too is a stretch, but you know how I can be. To put it honestly, if at all possible, I'm being overpaid to learn from some of the best while under the guise of teaching the stuff. | | Now you all know I am limited, both in brain power and being capable of all I forgot, but don't count me out. I have never had a happier experience while constantly reminding my peers there's no reason to get frustrated while collecting a respectable pay check. | | Just a note, if I've not already done so, my key responsibilities include stencil printing and all that goes with it and rework as a direct reflection of how I screwed up - up front. How's that in light of the fact one of my operators said we don't need no stinking procedures or check lists because we have six month's experience. This is from the mouth of a great looking lady who ran a batch of boards all the way through the BTU - UP F'N SIDE DOWN. | | Boogie and dont forget the tighter the crystalline structure - the less oxidation - but tin oxidizes readily. The question is how much and under circumstances, how quickly. | | MoonManBert | Earl: I was just funnin' ya, should i have put some of those smilies in my message. I didn't realize how sensitive you are.

This white tin stuff has a finer grain structure than gray tin, but there is also what I feature as "OSP like stuff" mixed in there also.

TTYL

Dave F

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Earl Moon

#11873

Re: Cleaning procedures for Entek-Plus Cu-106A | 27 April, 1999

| Dave said: | | | | So Earl, have you gone honest and haken a real job or is this a consulting project? | | | | | | TTYL | | | | | | Davebert | | | | | | | | DamnDaveBert, | | | | I know you didn't mean to insult such a sensitive one as me, but putting honesty and real together in the same sentence is pushing it. Actually, I'm doing "real" & "honest" work toegether under a contract. | | | | I know that too is a stretch, but you know how I can be. To put it honestly, if at all possible, I'm being overpaid to learn from some of the best while under the guise of teaching the stuff. | | | | Now you all know I am limited, both in brain power and being capable of all I forgot, but don't count me out. I have never had a happier experience while constantly reminding my peers there's no reason to get frustrated while collecting a respectable pay check. | | | | Just a note, if I've not already done so, my key responsibilities include stencil printing and all that goes with it and rework as a direct reflection of how I screwed up - up front. How's that in light of the fact one of my operators said we don't need no stinking procedures or check lists because we have six month's experience. This is from the mouth of a great looking lady who ran a batch of boards all the way through the BTU - UP F'N SIDE DOWN. | | | | Boogie and dont forget the tighter the crystalline structure - the less oxidation - but tin oxidizes readily. The question is how much and under circumstances, how quickly. | | | | MoonManBert | | | Earl: I was just funnin' ya, should i have put some of those smilies in my message. I didn't realize how sensitive you are. | | This white tin stuff has a finer grain structure than gray tin, but there is also what I feature as "OSP like stuff" mixed in there also. | | TTYL | | Dave F | Yeah, I'm known as mr sensitivity. I always enjoy your enlightening comments and an occassional opportunity to vent. Hell, YOU NEVER SEE ME GETTING PISSED OFF. Ahem.

I appreciate your stuff on coatings especially as we are embarking on a great adventure here as a possible departure from HASL. Having worked with OCC/OSP's since the early 70's and especially during the 80's when IBM was using the stuff like candy, I have a reasonable respect for it when properly applied, handled, and used..

The finer grain structure found in white tin coatings is interesting and may provide the key to why it works better. However, it's still not the whiskering I worry about. It's the oxidation. I just can't get over that part yet, but I've not worked with it extensively.

Keep on kepping on Dave and special regards,

Earl

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