Gerard, stand by for a tussle. I tried to defend the current ENIG
technology but the "silver guys" will not listen. Chinese technology, when
it comes to electronics, was all inherited from the good old USA and Japan.
Printed circuit boards and gunpowder have a slightly different technology.
The Chinese do a good job using US developed and tested technology and
they do it cheaper. US fabricators and chemical suppliers spent the big
bucks developing the processes driven by customer need and then we give
that technology along with our jobs to China. The Chinese copy an ancient
technology-"flash gold" - and whoopee-big deal.
At 06:51 AM 10/12/2005, you wrote:
>Lee - as co-chairman of 4552 I have to take exception to your continuing
>negative comments on ENIG. You may be the most unlucky individual on the
>planet continuously finding the remaining bad ENIG suppliers, but ENIG is a
>mature, high reliable surface finish. We created the 4552 document to be
>used to weed out the bad suppliers as well as defining a realistic deposit
>thickness to provide a reliable surface finish with excellent solderability
>and shelf life. The days of "black pad", whatever the true definition is,
>are over. Both myself and my committee would be delighted to review your
>data that has the black pad phenomena tied directly to a deposit over 4
>micro inches, perhaps you could stop by the 4-14 meeting at Los Vegas.
>Chemical suppliers, FAB houses and industry have worked to produce a deposit
>that is multifunctional and world class. If you read the technical paper in
>the back of 4552, you will see that a 1 micro inch deposit was tested as
>the lowest deposit thickness, which I am still testing in real time,
>unprotected going on for 42 months. We obviously did not spec 1 micro inch
>minimum as it is not a practical deposit thickness to maintain on a daily
>basis, but it proves the point that thin I Au protects the underlying Ni
>very well, contrary to you own experiences unfortunately.
>
>Regards
>
>
>Gerard O'Brien
>Co-chairman 4-14
>.
>
>-----Original Message-----
>From: Lee Parker [mailto:[log in to unmask]]
>Sent: Tuesday, October 11, 2005 9:45 PM
>To: [log in to unmask]
>Subject: Re: [TN] Hasl
>
>Joel
>
>
>
>I am glad to here that you are successfully using ENIG boards;
>unfortunately this has not been the case with some other OEMs and CMs.
>Almost every week in this forum, I see a report of a problem with ENIG. I
>myself spent this spring moving several clients from ENIG to other
>solderability coatings. It has been my experience that if the gold
>thickness is <2 microinches there is a serious risk of poor solderability.
>If the gold thickness is> 4 microinches black pad may become a problem.
>The issue can also be elevated or diminished by the particular plating
>chemistry and the ability of the fabricator to control the process.
>
>
>
>Consequently, I often work with clients to evaluate and migrate too other
>hard metal finishes such as immersion silver and flash gold. The
>attributes of immersion silver have been discussed here at length many
>times and I am an advocate. I installed the first immersion silver line in
>North America at the AT&T plant in Richmond. I then worked with most of
>the AT&T assembly locations to verify the process.
>
>
>
>Flash gold is more recent and is found mostly in Chinese PCB shops where
>it has been resurrected and improved upon. In fact, we used a similar
>process at the AT&T facility in Richmond many years ago for "other" OEM
>boards. Most Chinese shops have installed the process and have made
>substantial improvements. The price is competitive. I along with others
>will be giving a paper on this process at the IPC February meeting.
>
>
>
>As an aside, this is probably the first novel technology innovation to
>originate in the Chinese PCB industry and we should all take notice. I
>believe we are seeing the same ingenuity in the Chinese PCB shops that
>Marco Polo found on his first visit to China when he returned to Venice
>with firecrackers and gun power.
>
>
>
>Best regards
>
>
>
>Lee
>
>
>
>J. L. Parker Ph.D.
>
>JLP Consultants LLC
>
>(804) 779 3389
>
>
>
>
>
>-----Original Message-----
>From: TechNet [mailto:[log in to unmask]] On Behalf Of Joel Mearig
>Sent: Tuesday, October 11, 2005 3:54 PM
>To: [log in to unmask]
>Subject: Re: [TN] Hasl
>
>
>
>Lee,
>
>Good input that I agree with. However, I was wondering if you could
>further
>
>discuss the "flash" vs. "ENIG" issue. I have been using ENIG on my Pb-free
>
>assemblies for about 7 years with very little problems. If I am missing
>
>something further education would be extremely helpful. Thanks
>
>
>
>Joel Mearig
>
>Delta Tau Data Systems, Inc.
>
>
>
>-----Original Message-----
>
>From: TechNet [mailto:[log in to unmask]] On Behalf Of Lee parker
>
>Sent: Tuesday, October 11, 2005 10:03 AM
>
>To: [log in to unmask]
>
>Subject: Re: [TN] Hasl
>
>
>
>Ramon
>
>
>
>After reflowing a soldered surface, you will form a meniscus which will
>
>interfere with SMT component placement. To avoid the problem I suggest a
>
>flat metal finish such as immersion silver or flash gold (not ENIG)
>
>
>
>Best regards
>
>Lee
>
>
>
>J. Lee Parker, Ph.D.
>
>JLP Consultants LLC
>
>804 779 3389
>
> ----- Original Message -----
>
> From: Dehoyos, Ramon<mailto:[log in to unmask]>
>
> To: [log in to unmask]<mailto:[log in to unmask]>
>
> Sent: Tuesday, October 11, 2005 12:52 PM
>
> Subject: [TN] Hasl
>
>
>
>
>
>
>
> Hi technetters:
>
> Is there a fine pitch limit to the use of HASL board plating
>
> finish due to its variation in thickness? Does selective solder strip
>
> and reflow plating, SSSR, have a significant advantage over HASL? Any
>
> comments relating to platting finish would be greatly appreciated. I
>
> thank you for your comments.
>
> Ramon
>
> ME
>
> 410.552.2210
>
>
>
> ---------------------------------------------------
>
> Technet Mail List provided as a service by IPC using LISTSERV 1.8e
>
> To unsubscribe, send a message to
>
>[log in to unmask]<mailto:[log in to unmask]> with following text in
>
> the BODY (NOT the subject field): SIGNOFF Technet
>
> To temporarily halt or (re-start) delivery of Technet send e-mail to
>
>[log in to unmask]<mailto:[log in to unmask]>: SET Technet NOMAIL or (MAIL)
>
> To receive ONE mailing per day of all the posts: send e-mail to
>
>[log in to unmask]<mailto:[log in to unmask]>: SET Technet Digest
>
> Search the archives of previous posts at:
>
>http://listserv.ipc.org/archives<http://listserv.ipc.org/archives>
>
> Please visit IPC web site
>
>http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/conten
>tp
>
>age.asp?Pageid=4.3.16> for additional information, or contact Keach
>Sasamori
>
>at [log in to unmask]<mailto:[log in to unmask]> or 847-615-7100 ext.2815
>
> -----------------------------------------------------
>
>
>
>---------------------------------------------------
>
>Technet Mail List provided as a service by IPC using LISTSERV 1.8e
>
>To unsubscribe, send a message to [log in to unmask] with following text in
>
>the BODY (NOT the subject field): SIGNOFF Technet
>
>To temporarily halt or (re-start) delivery of Technet send e-mail to
>
>[log in to unmask]: SET Technet NOMAIL or (MAIL)
>
>To receive ONE mailing per day of all the posts: send e-mail to
>
>[log in to unmask]: SET Technet Digest
>
>Search the archives of previous posts at: http://listserv.ipc.org/archives
>
>Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
>
>for additional information, or contact Keach Sasamori at [log in to unmask] or
>
>847-615-7100 ext.2815
>
>-----------------------------------------------------
>
>
>
>---------------------------------------------------
>
>Technet Mail List provided as a service by IPC using LISTSERV 1.8e
>
>To unsubscribe, send a message to [log in to unmask] with following text in
>
>the BODY (NOT the subject field): SIGNOFF Technet
>
>To temporarily halt or (re-start) delivery of Technet send e-mail to
>[log in to unmask]: SET Technet NOMAIL or (MAIL)
>
>To receive ONE mailing per day of all the posts: send e-mail to
>[log in to unmask]: SET Technet Digest
>
>Search the archives of previous posts at: http://listserv.ipc.org/archives
>
>Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
>for additional information, or contact Keach Sasamori at [log in to unmask] or
>847-615-7100 ext.2815
>
>-----------------------------------------------------
>
>
>---------------------------------------------------
>Technet Mail List provided as a service by IPC using LISTSERV 1.8e
>To unsubscribe, send a message to [log in to unmask] with following text in
>the BODY (NOT the subject field): SIGNOFF Technet
>To temporarily halt or (re-start) delivery of Technet send e-mail to
>[log in to unmask]: SET Technet NOMAIL or (MAIL)
>To receive ONE mailing per day of all the posts: send e-mail to
>[log in to unmask]: SET Technet Digest
>Search the archives of previous posts at: http://listserv.ipc.org/archives
>Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
>for additional information, or contact Keach Sasamori at [log in to unmask] or
>847-615-7100 ext.2815
>-----------------------------------------------------
>
>---------------------------------------------------
>Technet Mail List provided as a service by IPC using LISTSERV 1.8e
>To unsubscribe, send a message to [log in to unmask] with following text in
>the BODY (NOT the subject field): SIGNOFF Technet
>To temporarily halt or (re-start) delivery of Technet send e-mail to
>[log in to unmask]: SET Technet NOMAIL or (MAIL)
>To receive ONE mailing per day of all the posts: send e-mail to
>[log in to unmask]: SET Technet Digest
>Search the archives of previous posts at: http://listserv.ipc.org/archives
>Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
>for additional information, or contact Keach Sasamori at [log in to unmask] or
>847-615-7100 ext.2815
>-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
