Not that Francois needs it, but the following, in case it didn't show up on
one of my previous posts, is a good checklist:

MSD Audit Checklist

General

-
Is there a general procedure in place covering all key elements of moisture
sensitive device control. Has this procedure been updated to reflect the
latest revision the joint IPC/JEDEC standard J-STD-033 released in May 1999.
-
Is there a site coordinator responsible to update and manage all elements of
the moisture sensitive device control program

Training

-
Is there a formal training program in place for all employees which covers
the key elements of moisture sensitivity : physical phenomena,
classification, standard, key elements of internal procedures.
-
Is there a training in place for the technical staff on the subject of
moisture sensitivity, including the following additional elements of
information : recognize the symptoms of moisture sensitive defects,
understand the potential failures modes, process yield and reliability field
failures
-
Compare the training effort on the subject of MSD relative to ESD

Factory environmental conditions

-
Is there a procedure in place to verify and log the temperature and RH level
on the production floor during the whole year.
-
Verify if the maximum RH level ever exceed 60% RH. Is there a procedure in
place to take actions if this limit is exceeded.
-
Does this action plan take into account the derating factor specified by
IPC/JEDEC to reduce the maximum floor life accordingly (Ref. J-STD-033, table 9)
-
Does the procedure/system take into account the de-rating factor to extend
the floor life and minimize baking when the ambient conditions are below 60% RH

Incoming Inspection

-
Is there a central database of all part numbers that are moisture sensitive,
including their sensitivity level.
-
Is it used at incoming inspection to identify when MSD are received not
properly packaged and identified. Is it accessible on the production floor
to verify components that are not properly identified.
-
Does the incoming inspection procedure take into account all requirements of
the IPC/JEDEC standard : quality of seal, seal date, status of indicator
(Ref. J-STD-033, section 8.1). This verification must also be performed on
the production line if this is where the bags will be opened.
-
Are the dry bags sometimes opened for inspection ? Is there proper
equipment, materials and trained employees to re-seal bags within one hour
from opening

MSD Component identification and tracking

-
Is there a method in place to identify individual trays and reels containing
MSDs once they are removed from their dry bags.  Does it include all
relevant information, including sensitivity level and expiration date/time.
-
If the information is not directly attached to the lowest level container
(i.e. tray or reel), verify if all information can be associated with the
proper material in a reliable manner.
-
Is there a method in place to keep track and update remaining floor life for
each tray and reel from the time they are removed from their dry bag, until
all the components have been placed prior to reflow. (including kitting,
programming, tape and reel, placement, dry storage, etc.)
-
Is there a method in place to provide visibility on all the MSD and the
associated remaining floor life while they are loaded on feeders and
placement machines during production.
-
Is there a method in place to return all partial trays and reels into dry
storage after they are removed from the placement machine.

Dry storage

-
Important Note : Make sure that the procedure does NOT assume that the clock
of exposure time is stopped during dry storage

-
How are components identified inside dry cabinets, and re-sealed dry bags :
This information must contain : PN, sensitivity level, maximum floor life,
prior exposure time and cumulative time spent in dry storage
-
Is there a method in place to take into account the time spent in dry
storage and to update the remaining floor life accordingly, based on the
rule for short duration exposure. (i.e. less than 8 hours of exposure time,
followed by 5X in dry storage)
-
Is there a procedure or system in place to insure that the RH level is less
than 10% in the dry cabinets
-
Verify the materials for re-sealing dry bags. The Moisture Barrier Bags
(MBB) must have a rated Water Vapor Transmission Rate (WVTR) of <= 0.002
gm/100 in.2 in 24 hours at 40C after flex testing per condition E of ASTM F
392-93.
-
Make sure that the proper size desiccant packs, in a dry condition, and
humidity indicators are placed inside every re-sealed dry bag.

Bake

-
What is the default bake condition ? It should NOT be 24 hours at 125C or
192 hours at 40C. Theses values are based on the obsolete IPC and JEDEC
standards and they have since been increased to 48 hours at 125C or 68 days
at 40C
-
Is there a method in place to minimize the duration of bake and the
resulting degradation of components, based on the IPC/JEDEC table, taking
into account the sensitivity level and body thickness of the components
-
Is there a procedure in place to prevent operators from loading low
temperature carriers in a high temperature bake cycle
-
Is there a method, log book, or otherwise to control how long the parts have
been in the bake oven and to make sure that components are not removed
before the cycle is complete
-
Is there a method in place to identify which components have been already
through one bake to prevent multiple baking cycles.

Double side reflow

-
Are there products with MSD using double-side reflow process ?
-
Is there a process in place to insure that the side with MSD is run last
-
If there are MSD on both sides, is there a method in place to account for
the time spent between the first and second side reflow process. (this time
must be added to the prior exposure time for each MSD).

Rework and Repair

-
Is there a method to identify which components are moisture sensitive on a
finished PCB
-
Is there a procedure in place to bake PCBs before removing MSD components
using hot air rework tools.
-
Is there a procedure in place to make sure that only dry components are
replaced with hot air rework tools.




For additional information on the subject of moisture sensitivity consult
the MSD knowledge base at www.cogiscan.com




He also has a very good paper, in .pdf format, you might have already read.
If not, he will supply it - won't he Francois.

MoonMan

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