May be the board has been reworked by powder polishing such as jet scrubbing or manual sanding (Al2O3 and Si2O4)
 

Thanks and best regards,
Ken Chow
OEM & Business Development Director,
Enthone, Cookson Electronics
Mobile: +852-9408-4736


----- Original Message -----
From: Tan Geok Ang [[log in to unmask]]
Sent: 11/22/2011 10:04 ZE8
To: <[log in to unmask]>
Subject: Re: [TGAsia] Non-wetting on PTH top surface



Did you EDX the different between the non-wetting points vs. solder
joints?

Are you using ImAg PCB surface?

 

________________________________

From: TGAsia [mailto:[log in to unmask]] On Behalf Of Rainbow Zhang
Sent: Monday, 21 November 2011 10:06 AM
To: [log in to unmask]
Subject: Re: [TGAsia] Non-wetting on PTH top surface

 

 

Hi All,

 

I want to share a case with you all here and collect your comments as I
get a little stuck in determining what is real root of the issue.

 

Referring to the photo attached the solder pad was not fully covered by
solder after manually solder, not meeting the IPC-610 requirement of at
minimum of 75% solder be covered around the pad. observed under digit
camera there some darkish residue remained on there, and main elements
spot by EDX as illustrated, to what surprise is where did Al and SI come
from since the used solder material do not contain these two elements.

 

 

 

Legal Disclaimer: The information contained in this message may be
privileged and confidential. It is intended to be read only by the
individual or entity to whom it is addressed or by their designee. If
the reader of this message is not the intended recipient, you are on
notice that any distribution of this message, in any form, is strictly
prohibited. If you have received this message in error, please
immediately notify the sender and delete or destroy any copy of this
message 
______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud
service.
For more information please contact helpdesk at x2960 or
[log in to unmask] 
______________________________________________________________________

Legal Disclaimer: The information contained in this message may be
privileged and confidential. It is intended to be read only by the
individual or entity to whom it is addressed or by their designee. If
the reader of this message is not the intended recipient, you are on
notice that any distribution of this message, in any form, is strictly
prohibited. If you have received this message in error, please
immediately notify the sender and delete or destroy any copy of this
message 
______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud
service.
For more information please contact helpdesk at x2960 or
[log in to unmask] 
______________________________________________________________________


______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________NOTE: This electronic message (including any attachments) contains information which may be privileged, confidential , or copyrighted under applicable law. The information is intended solely for the use of the individual(s) or entity named above. If you are not the intended recipient, please be aware that any disclosure, viewing, copying, alteration, dissemination, distribution of, or use of the contents of this information in whole or in part is strictly prohibited. If you received this electronic transmission in error, please notify the sender immediately by replying to this message and delete the copy you received.

______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________