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Baking MSDs in tubes?

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#48079

Baking MSDs in tubes? | 1 March, 2007

Is anyone doing this? What is the proper temp to bake tubes at? Is there an easier solution?

Thanks in advance

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CL

#48151

Baking MSDs in tubes? | 5 March, 2007

JDumont,

Baking in tubes is possible. Max temp for tubes is around 50 degrees C. Some will withstand more than others. You would have to do some experimenting on the tubes that you do have to see what temp they can take. JEDEC 033-A stated that a level 3 (< or = 2.0 mm thick) bake time will be 23 days for floor life met, 37 days for a saturated part.

Hope this helps

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#48152

Baking MSDs in tubes? | 5 March, 2007

Well that is completly unacceptable for me and im sure 99% of mfgrs. I have seen people use extruded aluminum tubes. They any good? Know anyone who sells em? Thanks

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Rob

#48156

Baking MSDs in tubes? | 5 March, 2007

We've got away with 90C before, however at 120C they tend to bananna and it isn't easy to remove all of the product then, and some of the legs get damaged (we always received waffle packs then one day tubes arrived & the operator baked as usual....).

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#48157

Baking MSDs in tubes? | 5 March, 2007

Yea, we have A LOT of tubes. We use lots of SOICs. I need to find something as this will start to become a big issue now that we have a tracking system in place.

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#48161

Baking MSDs in tubes? | 5 March, 2007

Join the "big issue" club. We were just reading the "fine print" (no, it wasn't fine print...) in J-STD-033, and noticed that we overlooked the requirement that when baking at 40C (or any temp below 100C) the humidity in the oven must be controlled below 5%. We were just 'happily' baking away for weeks at a time, and probably not really accomplishing anything.

Just remember that reels are low temp packaging too. We all use LOTS of IC's.

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Hussman

#48164

Baking MSDs in tubes? | 5 March, 2007

Nitrogen cabinets.

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#48176

Baking MSDs in tubes? | 5 March, 2007

I've wondered about the 5% spec myself. Section 4.2 points out that "The oven used for baking shall be vented and capable of maintaining the required temperature at less then 5% RH.", leading me to believe this spec even applies to ovens used to bake at over 125C.

Since we don't have humidity gauges that can take 125C, we've just kind of ignored that requirement. How are the more controled shops out there monitoring the humidity in their ovens, and is there really any reason to worry about humidity when baking at over 100C?

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#48178

Baking MSDs in tubes? | 5 March, 2007

De-Humidification cabinets. The draw back with Nitrogen is that it does not reset clock life. The De-Humidification cabinets will remove moisture and has been added for some levels in the standard.

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#48181

Baking MSDs in tubes? | 5 March, 2007

Baking, IC tubes, metal * Perfection Products; 1320 S Indianapolis Ave, Lebanon IN 46052; 765-482-7786 fax 7792 http://www.perfection-products.com

* Antistatic Industries; 130 Gamewell St POBox 460 Hackensack, NJ 07602-0460; 201-489-4400 fax 7654 http://www.antistaticindustries.com

* Malaster; 376 Caribbean Dr, Sunnyvale, CA 94089; 408-745-0104 fax 0835 http://www.malaster.com

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#48197

Baking MSDs in tubes? | 6 March, 2007

Table 4-1 only specs the humidity requirement for bake temperatures below 100C. It is conspicuously absent above that. I believe it is because moisture is in its gaseous state above 100C.

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#48634

Baking MSDs in tubes? | 25 March, 2007

Let me explain. At 125 degrees C, the oven is above the boiling point of water. It will be vaporized and eventually be vented from the oven. However at temperatures of 90 degrees c and lower the relative humidity becomes an issue. For the life of me, I can't find a oven that can perform the 90 degree C or 40 degrees C schedules in IPC/JEDEC J-Std-033C.

We have been working like dogs to develop a 70 degree C, 24-hour process that can conform to J-Std-033C and remove moisture from plastic tubed SMT MSD'S. I think we have reached our goal.

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#48653

Baking MSDs in tubes? | 26 March, 2007

That's what I thought. The humidity req't would be a non-issue when you are able to bake at 125C.

Can you share details on how you bake at 70C?

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#48657

Baking MSDs in tubes? | 26 March, 2007

The issue is of drying moisture-sensitive surface-mounted packages is likely to become even more of a baking-headache in light of the upcoming "D" revision to IPC/JEDEC 020.

We have taken a simular approach that a major cellular phone firm took in 1994. Their process study had some obvious errors but the truth of the matter was that they were able to dry over 10 million, highly moisture-sensitive packages at 70 degrees C in just 24-hours.

We spent over two-years, updating and fine-tuning the process. Most importantly, the alternative process conforms to J-Std-033B. Because vendor-gernerated process data is commonly viewed with suspicion, all to the experemental work was performed by leading industry firms.

We have made a CD-ROM available for the asking that explains our approach in detail. Contact me at sleech@qwest.net. We will be happy to provide a disk

We are IDC,.. the oven manufacturer that hates baking.

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#48658

Baking MSDs in tubes? | 26 March, 2007

Paul:

You are dead-on! Desiccant and nitrogen cabinets are a great way to maintain the current moisture content level of a MSD package. But if you look at the 40 degree C schedule (Table 4-1) in J-Std-003B, you will find that the drying capability of a 40 degree C schedule will take forever.

A portion of the industry problem with drying these packages is that J-Std-033B strives to completely dry the packages. This resets the "floor-life" clock. We do not commonly want to recover the full floor-life. We simply want the reset it to a point where we can safely mount and reflow our MSD compenents and get on with business.

Best regards

Charles Leech

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