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MSD Storage

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MSD Storage | 25 October, 2012

I have read through the IPC/JEDEC J-STED-033.1 standards regarding bake and storage of MSDs.

The lowest bake in the standard is <5% RH @ 40degC

the table of storage conditions for unlimited shelf life are <5%, but only indicate a temp between 20deg and 35deg.

Also - it indicates that if device is baked below 90degC that there is no limit on bake time (due to oxidation issues)

My question is Can you store MSDs permanently at <5% 40degC?

My reason for asking this is to remove the need for a second cabinet, or for resealing of bags. If this was possible to do, it will make managing the whole system a lot easier.

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MSD Storage | 6 November, 2012 states, ...If the bake temperature is not greater than 90 °C, there is no practical limit on bake time...

If I interpret that correctly, then you may keep MSDs in a 40 deg. C oven indefinitely with no adverse conditions.

Instead of opting to buy a dry cabinet, we put all our MSDs in a 40 deg. C oven when not loaded on the machine. Since the clock will pause in any environment <10% RH, we can greatly extend the time outside of a MBB. A 40C oven will also reset the clock after a LONG period of time, which I don't believe is an option for 2, 2a, 3 over 12hrs. or 4,5,6 after 8hrs. using a dry cabinet...baking is mandatory at that point.

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MSD Storage | 8 November, 2012

Make sure that the 40 degree C oven is getting to less then 5% RH inside especially for any applications where you need to dry may surprise you that many ovens set at 40 C will have an internal RH of @ 20~30%....and that is not dry enough to store device...that is why IPC states drying conditions of 40 C and less then 5% RH...NOT just drying at 40 check the RH in the 40 C oven...if it is higher then 5% then you are not drying devices, if it is less then 10% then the clock is paused, but if it is over 10% then there is no real benefit of long tern storage in a 40 C oven that is not achieving less then 10%. But to answer your question...yes you can store MSDs at 40C and less then 5% RH indefinitely, but don't assume your 40 C oven has an internal RH of less then 5%.

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MSD Storage | 22 November, 2012

For you info there is a maker of humidity cabninets in UK called Mekko that offers full active drying <5% and heater control option to 40 Deg C.....

They have high speed desicant unit that is rapid and runs continuously....

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