[SI-LIST] AW: Re: ENIG vs Electroplated Gold over Electroplated Nickel
- From: "Ippich, Alexander" <alexander.ippich@xxxxxxxxxxxxx>
- To: <scott@xxxxxxxxxxxxx>, <Jeremy.Scuteri@xxxxxxxxxx>
- Date: Fri, 14 Mar 2014 08:28:06 +0100
Jeremy,
regarding the question if Gold over electroplated Nickel would be better than
ENIG:
Typically, electroplated NiAu is applied as a full body finish, prior to
soldermask application. This is because for that finish, the NiAu layer is
typically used as an etching resist to structure the outerlayers. That said,
you end up with having Nickel over the whole length of your outerlayer traces,
which is not desirable from a loss perspective.
ENIG (electroless-Ni over immersion-Au) can be applied as a full body finish,
or (and that's the more common way) as a selective finish, because it is
applied after soldermask. In the second case, you do not end up with Ni on your
traces, as long as they are covered by soldermask. This is described as SMOBC
(soldermask over bare copper) processing.
So if you are concerned with higher frequency loss and you want to use a
Nickel-Gold finish, the use of electroless/immersion finishes is far better
than the use of the electroplated version.
Best regards,
alex
-----Ursprüngliche Nachricht-----
Von: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] Im
Auftrag von Scott McMorrow
Gesendet: Thursday, March 13, 2014 10:48 PM
An: Jeremy.Scuteri@xxxxxxxxxx
Cc: si-list@xxxxxxxxxxxxx
Betreff: [SI-LIST] Re: ENIG vs Electroplated Gold over Electroplated Nickel
Jeremy
Yuriy Shlepnev of Simberian and I have written a research paper on this.
Slides from our presentation are available at the link below. In short, it is
the Nickel that is the problem. There is no problem with using ENIG or other
nickel-gold plating over pads. Over traces, you will see increased losses.
Whether the losses are substantial enough to cause problems with your design
will depend on your design.
http://www.simberian.com/Presentations/NickelCharacterizationPresentation_emc2011.pdf
On Thu, Mar 13, 2014 at 5:17 PM, Scuteri, Jeremy
<Jeremy.Scuteri@xxxxxxxxxx>wrote:
> I am trying to understand when ENIG should be avoided (if ever). I
> have heard that it should be avoided on outside layers because it is
> very high loss. At what frequencies does this start to matter? Is
> Gold over Electroplated Nickel a better alternative?
>
> Thanks,
> Jeremy Scuteri
>
> ------------------------------------------------------------------
> To unsubscribe from si-list:
> si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
>
> or to administer your membership from a web page, go to:
> //www.freelists.org/webpage/si-list
>
> For help:
> si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
>
>
> List forum is accessible at:
> http://tech.groups.yahoo.com/group/si-list
>
> List archives are viewable at:
> //www.freelists.org/archives/si-list
>
> Old (prior to June 6, 2001) list archives are viewable at:
> http://www.qsl.net/wb6tpu
>
>
>
--
Scott McMorrow
Teraspeed Consulting Group LLC
16 Stormy Brook Rd
Falmouth, ME 04105
(401) 284-1827 Business
http://www.teraspeed.com
Teraspeed® is the registered service mark of Teraspeed Consulting Group LLC
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List forum is accessible at:
http://tech.groups.yahoo.com/group/si-list
List archives are viewable at:
//www.freelists.org/archives/si-list
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List forum is accessible at:
http://tech.groups.yahoo.com/group/si-list
List archives are viewable at:
//www.freelists.org/archives/si-list
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
- » [SI-LIST] AW: Re: ENIG vs Electroplated Gold over Electroplated Nickel - Ippich, Alexander
