TECHNET Archives

June 2007

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Vladimir Igoshev <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Vladimir Igoshev <[log in to unmask]>
Date:
Wed, 13 Jun 2007 11:32:04 -0400
Content-Type:
text/plain
Parts/Attachments:
text/plain (1 lines)
I'm not that sure about solder wetting larger areas after the second re-flow. On ENIG it usuallyh covers pads right away (unless the re-flow is screwed). As far as flux residue is concerne, then we don't know whether they use water soluable or non-clean one.



Regards,



Vladimir



-----Original Message-----

From: TechNet

To: [log in to unmask]

Sent: Wed Jun 13 11:10:33 2007

Subject: Re: [TN] Nickel barrier and RF applications



As I stated in my previous response to Vladimer, you are doing both.

Solder flows along the traces during the first reflow, forming an IMF

with the nickel, and providing a path (more conductive path) for the

signal. After the second reflow, the solder joints wet out a little

further, and a very small increase in the IMF also takes place.

While any of these is a very small change, the cumulative effect of

reflowing all of the solder joints is usually enough to create a

detectable improvement in performance of the high-RF/high-impedance

circuit performance.

Getting rid of additional flux also helps. 



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Paymon Sani

Sent: Wednesday, June 13, 2007 10:05 AM

To: [log in to unmask]

Subject: Re: [TN] Nickel barrier and RF applications



This is the million $ question. The assemblies are single sided with no

TH components. We simply pass them through the reflow oven for a second

time without changing the reflow profile or adding paste or flux to

improve the output power by 0.2 to 2 dB with majority of improvement at

0.5 dB! The question is what we are doing to the boards during the

second reflow:

1- Does it evaporate some of the flux residues?

2- Does it increase the IMC thickness?



The x-ray images of the before and after reflow are very similar, i.e.

we are not collapsing voids or creating new voids.





Paymon



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Vladimir Igoshev

Sent: June 13, 2007 10:39 AM

To: [log in to unmask]

Subject: Re: [TN] Nickel barrier and RF applications



I think, there is one question to ask. If ENIG (or rather the presence

of Ni) is the source of the problem, then why does 2nd reflow improves

the yield?





Regards,



Vladimir

AMD



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Paymon Sani

Sent: Wednesday, June 13, 2007 10:34 AM

To: [log in to unmask]

Subject: Re: [TN] Nickel barrier and RF applications



Thank you Steve,



This sheds a lot of light on the current RF product failures at my

company. As a matter of fact, my PCB supplier is applying ENIG on all

copper surfaces before the mask application!

Paul, thank you for initiating this trend.



Cheers,

Paymon



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory

Sent: June 13, 2007 10:23 AM

To: [log in to unmask]

Subject: Re: [TN] Nickel barrier and RF applications



I just realized that the URL may have wrapped. Try this one:



http://tinyurl.com/2vjenp



This might be the same one that Inge was talking about....



Steve Gregory



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory

Sent: Wednesday, June 13, 2007 9:00 AM

To: [log in to unmask]

Subject: Re: [TN] Nickel barrier and RF applications



Here's an article:



http://www.taconic-add.com/pdf/technicalarticles--effectsofsurfacefinish

.pdf



Steve Gregory



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Paymon Sani

Sent: Wednesday, June 13, 2007 8:57 AM

To: [log in to unmask]

Subject: [TN] Nickel barrier and RF applications



Hello John, is it documented anywhere?



Paymon



-----Original Message-----

From: John Burke [mailto:[log in to unmask]]

Sent: June 13, 2007 9:53 AM

To: 'TechNet E-Mail Forum'; Paymon Sani

Subject: RE: [TN] Plating



The nickel in enig  is not good for frequencies above 3 - 4 GHz





 

 

John Burke

 

(408) 515 4992

-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Paymon Sani

Sent: Wednesday, June 13, 2007 6:47 AM

To: [log in to unmask]

Subject: Re: [TN] Plating



Hello Inge,



This is very interesting! I did not make the connection between the

Nickel on the PCBs and the RF application. Are there any papers that

explain the sensitivity of RF applications to the Nickel barrier in ENIG

PCBs?

We are having trouble with a 5.8 GHz RF product right now. The assembly

meets the IPC-610D requirement. However, 25% of the products fail

testing. We reflow the failed assemblies for the 2nd time and 50% of

them pass testing! We do not know the RC of the failures. I was

suspecting the flux to be the root cause but could it be the Nickel

barrier?



Cheers,

Paymon







-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Hernefjord Ingemar

Sent: June 13, 2007 2:33 AM

To: [log in to unmask]

Subject: Re: [TN] Plating



Paul,



Lockheed Martin use a lot of platings. I'm not sure, but I have seen

Boron as a barrier somewhere, just can't find it right now. Anyway,

Lockheed as well as NASA use many special platings. Non-magnetic, guess

you have a RF application that need low-loss lines.



http://supplier.external.lmco.com/supplier/po_information/specpro2.htm





I was myself looking for a non-magnetic finish once, and if I remember

right, there is a difference between EN and EN. The acidous electroless

nickel is not ferromagnetic, while alcaline electroless nickel is

somewhat ferromagnetic.



Borohydride electroless Nickel-Boron is probably non-magnetic too.



However, you should contact your plating chemist to verify, it was many

years since I mixed with this. (In earlier days, we had our own

chemists, many of them had piles of knowhow, but then came the

economist's era, and the chemists were kicked out)



Inge



 



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Stolar, Paul W

Sent: den 12 juni 2007 23:38

To: [log in to unmask]

Subject: [TN] Plating



We are using nickel as a barrier metal on a PC board for the pads. 



Are there any other barrier metals we can use which are non-magnetic.



Bare copper is not an option.



Paul Stolar

Materials/Reliability Engineer

Manufacturing Reliability Lead Engineer

Baker Atlas

713-625-5376

713-625-4949 (fax)



---------------------------------------------------

Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 15.0 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

-----------------------------------------------------



------------------------------------------------------------------------

----

-----------

Confidentiality Notice



This e-mail and any attachment(s) are intended for the individual or

entity to which this email is addressed and may contain information that

is confidential.  If you are not the intended recipient or an employee

or agent responsible for delivering this e-mail to the intended

recipient, please be aware that any dissemination, distribution or

copying of this communication is strictly prohibited.  If you have

received this in error, please notify the sender by telephone at

604.430.4336 or by return e-mail, and please delete or destroy all

copies of this communication.  Thank you!



---------------------------------------------------

Technet Mail List provided as a service by IPC using LISTSERV 15.0 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

-----------------------------------------------------





------------------------------------------------------------------------

---------------

Confidentiality Notice



This e-mail and any attachment(s) are intended for the individual or

entity to which this email is addressed and may contain information that

is confidential.  If you are not the intended recipient or an employee

or agent responsible for delivering this e-mail to the intended

recipient, please be aware that any dissemination, distribution or

copying of this communication is strictly prohibited.  If you have

received this in error, please notify the sender by telephone at

604.430.4336 or by return e-mail, and please delete or destroy all

copies of this communication.  Thank you!



---------------------------------------------------

Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 15.0 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 15.0 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

-----------------------------------------------------



------------------------------------------------------------------------

---------------

Confidentiality Notice



This e-mail and any attachment(s) are intended for the individual or

entity to which this email is addressed and may contain information that

is confidential.  If you are not the intended recipient or an employee

or agent responsible for delivering this e-mail to the intended

recipient, please be aware that any dissemination, distribution or

copying of this communication is strictly prohibited.  If you have

received this in error, please notify the sender by telephone at

604.430.4336 or by return e-mail, and please delete or destroy all

copies of this communication.  Thank you!



---------------------------------------------------

Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 15.0 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

-----------------------------------------------------



------------------------------------------------------------------------

---------------

Confidentiality Notice



This e-mail and any attachment(s) are intended for the individual or

entity to which this email is addressed and may contain information that

is confidential.  If you are not the intended recipient or an employee

or agent responsible for delivering this e-mail to the intended

recipient, please be aware that any dissemination, distribution or

copying of this communication is strictly prohibited.  If you have

received this in error, please notify the sender by telephone at

604.430.4336 or by return e-mail, and please delete or destroy all

copies of this communication.  Thank you!



---------------------------------------------------

Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 15.0

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

-----------------------------------------------------






ATOM RSS1 RSS2