Hi Steve,
If someone can answer this one with objective criteria, they better patent the answer.
Unfortunately from my experience, I've found that these issues are independent of each other
(unless you drop a board in a pile of dog poop in the plating room). In reference to handling
damage. As a customer, you do not want any incoming to you. As a manufacturer, Your transport
characteristics (slip sheeting, automation, operator traing/attitude, etc.) in conjunction with
the technology of the product (4 layer 062 thick using a .028 core, 1 ounce copper versus 12
layer 062 using .004" mil core with 1/4 ounce copper, line width of .010" versus .003" etc.) will
dictate your final results. I guess I've always viewed handling damage as a training/attitude
issue. There should be NONE, but accidents do happen. I guess to make a short story long, Your
handling will probably be organization dependent. I didn't even get into what would be
considered a "handling" defect because sometimes "handling" can be a catch all.
Now that I've bored the stuffing out of you with that, handling typically plays a small role
in contamination (key word- TYPICALLY), and is more related to the materials/process areas
(soldermask type and curing level/technique, resin to glass ratio of laminate, fluxes and
cleaning material such as aqueous versus semi aqueous, dwell time at soldercoat, blah, blah,
blah;). Also, contamination needs further definition, particulate, ionic, non ionic, etc.
The bottom line to the contamination question is that standards have been set ranging from
1mg/cm2 to 10mg/in2 for ionic as well as SIR (surface insulation resistance) numbers in the 10 to
the 8th Megohm range (sorry if i'm off here, been a while for me, and the memory is the second
thing to go).
I hope that I helped muddy the water for you on this, and I do apologize if I seem to have no
conclusive answer, but I am not truly aware of one and wanted to babble for a while (keeps my
hands busy).
SERIOUSLY THOUGH, I was hoping to give you some insight as to what I have seen and others
should have some interesting comments as well (please do not beat me up too bad on my answers, it
seems to be the first response to build on) JOHN WAITE
Stephen Ayotte wrote:
> I have a coworker who has asked me the following question:
>
> "As a function of the number of times that a part is handled is there any type
> of model or tool that can be used to predict the amount of handling damage and
> or contamination that would occur."
>
> This would be for a typical factory environment and for equipment and
> inspection operators, not in a clean room environment with lab coats, masks and
> gloves.
>
> Thanks.
>
> Stephen Ayotte, IMD Product Quality Engineer
> Phone (607) 755-1537, t/l 855-1537
> Pager (607) 755-7243 Pin #863 - external, 5-8888 Pin 2863 - internal
> Fax (607) 755-4649
> Stephen Ayotte
> IMD Product Quality Engineer. Laminate Chip Carriers
> Dept. 5QE, Bldg. 14-3, Office BB11
>
> ################################################################
> TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
> ################################################################
> To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
> To subscribe: SUBSCRIBE TechNet <your full name>
> To unsubscribe: SIGNOFF TechNet
> ################################################################
> Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information.
> For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
> ################################################################
################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe: SUBSCRIBE TechNet <your full name>
To unsubscribe: SIGNOFF TechNet
################################################################
Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################
|
