Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

SMTnet
»
Electronics Forum
»
0201

0201

Subscribe to Thread

I am working on 0201 development for my company in the UK, a... - Jun 14, 2001 by OEM BOY

Consider profiling from all of your problem components, not ... - Jun 18, 2001 by davef

look at ... - Jun 19, 2001 by davef

OEM Boy, Reflow depends on your paste type also. Are yo... - Jun 21, 2001 by J.D.

Yes, Pb Free is coming soon... I am studying both Sn/Pb and... - Jun 21, 2001 by OEM BOY

OEM Boy, This is an excellent question. Since I am on... - Jun 22, 2001 by J.D.

OEM BOY

#6905

0201 | 14 June, 2001

I am working on 0201 development for my company in the UK, and I am planning a rather extensive DOE for my reflow oven profile.

I am planning on studying various ramp rates, soak times, times above liquidus, peak temps, etc... My biggest concern is not basing it all on the 0201's since my PWB has larger parts as well... My output responses will be post reflow placement accuracy (measure with AOI), tombstoning (lack of it hopefully), shear tests, and thermal cycling until failure.

I got the paste printing down no problem and the pick and place machines I am using are working great.

Anyone have any experience with 0201 oven profiling? I am using a 7 zone oven, loads of flexibility.

Cheers!

reply »

davef

#6969

0201 | 18 June, 2001

Consider profiling from all of your problem components, not just your 0201.

reply »

davef

#6989

0201 | 19 June, 2001

look at http://www.uic.com/wcms/images.nsf/(graphiclib)/mc-2447+process+parameters+article.pdf/$file/mc-2447+process+parameters+article.pdf

reply »

J.D.

#7020

0201 | 21 June, 2001

OEM Boy,

Reflow depends on your paste type also. Are you using lead free or will you be going to lead free soon? If your are going to you might want to consider developing two different profiles for lead free and leaded pastes.

Good Luck!

J.D.

reply »

J.D.

#7021

0201 | 21 June, 2001

OEM Boy,

Good Luck!

J.D.

reply »

OEM BOY

#7030

0201 | 21 June, 2001

Yes, Pb Free is coming soon... I am studying both Sn/Pb and Pb Free solders. Obviously the profiles will be much different for both pastes.

Not to mention that one of my 0201 resistor vendors is switchng to Pb Free terminations in the near future!

So the real question with Pb Free is how to rework?? Do you use Sn/Pb solder to rework or try to use Pb Free?? Getting off the subject but I think this is a good question.

reply »

J.D.

#7038

0201 | 22 June, 2001

OEM Boy,

This is an excellent question. Since I am on the "I-want-to-sell-you-equipment-side" I do not have the hands-on experience that you do but, I do have a many engineers back at our factory who have dedicated their lives to these issues. From what they have told me, most all of our customers are using lead-free now. The repair process they use is nothing earth shattering. They have trained a few technicians to use the microscope with a soldering iron needle to do repair. The only twist on this is the use of hot air directly on the repair area. No, additional solder needed just what is on the board. The repairs also are for the greatest defect, which is tombstone and micro-tombstone. Using lead-free pastes, which have different wetting properties that Pb pastes, creates this type of defect. Meaning a Pb paste is more likely to wet evenly than a Pb-free paste. I hope this helps you.

Sincerely,

J.D. Talken Panasonic Create jtalken@panasonicfa.com

reply »