LED emmiters and moisture

[Matjazz]

When I bought LED emmiters from Farnell or Mouser I recieved them in a sealed antistatic bag with a desicant.
Just now I recieved Luxeon V2 from mouser and the package had this ticker on:

I tohught the shelf life of LEDs was nothing to be concerned about but now I’m not so sure. The spec sheet for Luxeon V2 says that JEDEC moisture sensitivity is level 1 and it doesn’t even talk about shelf life, but the sticker says different.
How catious are you with your emmiters?

[DavidEF]

I think they mean the contact surfaces. In order to get the best conductivity of both heat and electric current, you want a clean bond. So, the contact surfaces need to be kept clean and dry. But I don’t really know if that’s it. I’m mostly speculating.

[M3CSL]

arrow has the same text/print. they even send a humidity tester with the shipment, they are always pink though? Isn’t that bad? either way, they all worked for me.

[Matjazz]

I’ve looked into some more spec sheets

@Samsung LH351C spec sheet

1. LEDs must be stored in a clean enviroment. If the LEDs are to be stored for three months or more after being shipped from Samsung, they should be packed with a nitrogen-filled container (shelf life of sealed bags is 12 months at temperature 0-40°C, 0-90% RH)
2. After storage bag is opeend, device subjected to soldering, solder reflow, or other hight temperature processes must be:
   #* mounted within 672 hours (28 days) at an asembly line with a condition of no more than 30°C / 60% RH, or
   #* Stored at <10% RH
3. Repack unused devices with anti-moisture packing, fold to close any opening and then store in a dry place.
4. Devices require baking before mounting, if humidity card reading is >60% at 23+–5°C
5. Devices must be baked for 1 hour at 60±°C, if baking is required.

@Cree XP-G2 spec sheet

Moisture Sensitivity

• Cree recommends keeping XLamp LEDs in the provided, resealable moisture-barrier packaging (MBP) until immediately prior to soldering. Unopened MBPs that contain XLamp LEDs do not need special storage for moisture sensitivity.
• Once the MBP is opened, XLamp XP-G2 LEDs may be stored as MSL 1 per JEDEC J-STD-033, meaning they have unlimited floor life in conditions of ≤ 30 oC/85% relative humidity (RH). Regardless of the storage condition, Cree recommends sealing any unsoldered LEDs in the original MBP.

I paln to use Samsung leds for my next project and it looks like I’ll have to bake them. The question now is how to bake? Would a table top kitchen oven do?

[DavidEF]

@Matjazz

I’ve looked into some more spec sheets

I paln to use Samsung leds for my next project and it looks like I’ll have to bake them. The question now is how to bake? Would a table top kitchen oven do?

I would think there are two necessary attributes for an oven to bake the LEDs properly:

1. The oven has to be able to maintain the correct temperature setting fairly consistently.
2. The LEDs should be shielded somehow from the direct radiation from the elements, because the radiant heat might make them too hot.