Subject: | |
From: | |
Date: | Wed, 15 May 96 15:31:37 |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
To: Steve Quinn
Heurikon Corp
Hi Steve,
I am a Material Engineer with ERG Limited in Perth, Western Australia.
My responsiblities are semiconductors, crystals, LCD displays, RF
products and power supplies.
We have been creating a shelf life policy within our company and have
also discovered the problem with the humidity sensitive devices. We
initially thought of using the Moisture Barrier Bags (MBBs) but this
would require continual opening and sealing of the bags (pain!!!!!).
The most economical and time saving solution I have found is using
either a Desiccant Cabinet or Mechanically Refrigerated Forced Draught
Low Humidity Chamber.
The first option involves purchasing a Desiccator Cabinet, which does
not use air circulation, but uses desiccant in a bottom shelf to
provide the necessary RH. This is a low capital option, with a 1 cubic
metre cabinet costing about $4000 AUD. However, you will need to dry
or replace the desiccant at regular intervals.
The second option will require no maintenance as the Low Humidity
Chamber uses dry forced air to provide the RH environment. The cost is
a little more expensive with a 1 cubic metre unit costing $10,000.00
AUD.
The process in handling these devices becomes:
- Store in stock inside the Moisture Barrier Bags that the
manufacturer supplies them in. This gives them a shelf life of 12
months from sealed date.
- Once the MBB has been opened, move the ICs to the Humidity /
Desicannt cabinet for storage until production use. The environment of
the cabinet should be monitored by either digital indication of RH or
Humidity Indicator Cards.
- Return all unused ICs to the Humidity / Desiccant Chamber until
need.
If this is monitored properly, the ICs should stay within their ideal
storage condition.
If you have any questions about this, let me know. My email address is
[log in to unmask]
Michael Waller.
ERG Limited.
|
|
|