TECHNET Archives

February 2011

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:
"Stadem, Richard D." <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Stadem, Richard D.
Date:
Wed, 9 Feb 2011 16:44:01 -0600
Content-Type:
text/plain
Parts/Attachments:
text/plain (181 lines)
It is a custom built laser solder system developed and built at Analog Technologies Corp. in Burnsville.  We designed it and had an outside integrator build it for us. We wanted something that could do everything we needed, and none of the laser soldering machines on the market were capable nor are they yet. It uses a 60W laser, but has a total of four slots for different energy sources such as UV, another 150W laser for welding and cutting, and an IR source. All four slots are routed to the head, which can rotate and direct any of the energies at almost any angle above the work plane. It has a precision repeatability of 2 microns, and the source energy can be automatically programmed for both dwell time and power level, as well as the speed of the head, and the speed of rotation of the head. So for example, I can program it to lase in a figure "S" starting at the top at one speed and accelerating (or decelerating) down the "S" curve at different speeds while at the same time increasing or decreasing the laser power and angle of contact, and I can also vary the focal spot in size as I go. This allows me to focus lots of energy into a very small area, or less energy over a larger focal spot, or vice versa.
Analog uses the machine for a large variety of applications, including BGA, CSP, and flipchip ball attachment or reballing. They also use it to solder components, especially LEDs, that cannot withstand the heat of convection reflow. Other uses are ablation, microwelding, precision uv cure, precision IR cure of epoxies, laser marking of PWBs and metals, etc. It has a vision system mounted on the head as well so that we can safely watch the parts being soldered or whatever inside the work chamber. We can program it for an automatic inspection process using the camera system. So for example, we can first lase, then cure, then mark, then cut, etc, and not necessarily in any order, and then go back and inspect all of the work done afterwards.
We developed a reballing process that does not use nitrogen although the work chamber is plumbed and is sealed so it can be purged with nitrogen if so desired. However, we developed a chemical bath that evacuates all oxygen (100% of O2 is removed) during the laser soldering process so nitrogen is not required. The BGA or component body is never heated, all of the laser energy is directed to the ball. The result is perfectly pristine solder spheres (or columns) perfectly wetted to the BGA pads.
Read about it here:
http://www.analog-tech.com/Solder%20Ball%20Attachment%20Using%20Laser%20Soldering.pdf


From: Tan Geok Ang [mailto:[log in to unmask]]
Sent: Wednesday, February 09, 2011 2:43 PM
To: TechNet E-Mail Forum; Stadem, Richard D.; [log in to unmask]
Subject: RE: [TN] Vapour phase soldering?

Just wonder what brand/model of the laser system are you using to laser solder CCA?

________________________________
From: TechNet on behalf of Stadem, Richard D.
Sent: Wed 2/9/2011 10:36 PM
To: [log in to unmask]
Subject: Re: [TN] Vapour phase soldering?

It is not an issue. While initially some parts may take slightly longer, the heating of the entire CCA during vapor phase soldering is very uniform, especially for high-mass CCAs. It is the best mass reflow method available, followed by convection oven, and lastly infrared in terms of temperature control (minimization of thermal gradients). There are other reflow methods that are more precise, such as laser soldering which I do a lot of, but that is not considered to be mass reflow.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Thayer, Wayne - IIW
Sent: Wednesday, February 09, 2011 6:54 AM
To: [log in to unmask]
Subject: Re: [TN] Vapour phase soldering?

I haven't used vapor phase, but it would seem that while the temperature of the vapor bath is extremely controlled, the rate of heating can be an issue, not only for hitting a defined profile, but because the rate of heat absorption is mostly a function of surface area.  So if you have a small but thermally massive device next to a large but low mass device, then you will have quite a bit of delta T during the cycle.

But I haven't seen mention of the above principle during this thread.  Is it because it's not really an issue?

Wayne Thayer

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Graham Naisbitt
Sent: Wednesday, February 09, 2011 6:30 AM
To: [log in to unmask]
Subject: Re: [TN] Vapour phase soldering?

Techies

I know that there are solvents with very specific boiling points from 185C to >280C at 5C or 10C increments.

When I was involved in this technology, we used a 220C BP solvent that worked superbly with SAC305 and similar lead-free alloys that gave us a 1C DeltaT.

I would avoid high BP solvents unless your alloy really demands it. Of course part of the problem with most systems is maintaining and controlling the T profile. We did it in our equipment using a sealed chamber. That patented technology is, I believe, now exclusively available out of REHM - with whom I have no association, in case anyone was wondering!

Hope this helps

Graham N

Gen3 Systems, UK
www.gen3systems.com

On 8 Feb 2011, at 20:43, Paul Edwards wrote:

> Have used Alpha WS-809 at 240C if the profile is relatively peaky...
>
> Paul
>
> Paul Edwards
> Process/Quality Engineering
> Surface Art Engineering
>
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Julie Silk
> Sent: Tuesday, February 08, 2011 12:37 PM
> To: [log in to unmask]
> Subject: Re: [TN] Vapour phase soldering?
>
> For the first, we use VPR at a couple of suppliers, Jabil and Venture, but they
> don't have the capability at all sites.
>
> For the second, the concern is that the standard flux used in tin-lead paste
> typically will not survive 240C.  It will burn out and you won't get good joints.
> You can use tin-lead with higher temperature flux.
>
> ---------------------------------------------------
> 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.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
> -----------------------------------------------------
>
>
> ==============================================================================
>
> This email and any attachments thereto may contain private, confidential, and
> privileged material for the sole use of the intended recipient. Any review, copying,
> or distribution of this email (or any attachments thereto) by others is strictly prohibited.
> If you are not the intended recipient, please contact [log in to unmask]
> immediately and permanently delete the original and any copies of this email and
> any attachments thereto.
>
> ==============================================================================
>
>
> ______________________________________________________________________
> This email has been scanned by the MessageLabs Email Security System.
> For more information please contact helpdesk at x2960 or [log in to unmask]
> ______________________________________________________________________
>
> ---------------------------------------------------
> 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.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
> -----------------------------------------------------


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

---------------------------------------------------
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.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

This e-mail and any files transmitted with it may be proprietary and are intended solely for the use of the individual or entity to whom they are addressed. If you have received this e-mail in error please notify the sender.
Please note that any views or opinions presented in this e-mail are solely those of the author and do not necessarily represent those of ITT Corporation. The recipient should check this e-mail and any attachments for the presence of viruses. ITT accepts no liability for any damage caused by any virus transmitted by this e-mail.

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

---------------------------------------------------
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.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

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

---------------------------------------------------
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.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

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

---------------------------------------------------
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.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

ATOM RSS1 RSS2