TECHNET Archives

April 1999

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Joe Felts <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Thu, 22 Apr 1999 21:42:48 -0700
Content-Type:
text/plain
Parts/Attachments:
text/plain (133 lines)
Albert,

1. Prepare an inventory of coupons about 4"x 4" square (using your NC
router) in a thin-core laminate - 0.008" 1/1 for example.  Thinner cores
will minimize moisture absorption and make the copper weight more
significant than the laminate weight.
2. Keep the coupons in the lab.
3. Lab personnel bake and then weigh the coupon(s) on a sufficiently
sensitive scale.
4. Run coupon(s) through the line.
5. Return coupon(s) to the lab, bake again, weigh and convert weight loss
to etch depth.
6. Run a test to see if you can eliminate the bake steps without
appreciable error.

Joe Felts



-----Original Message-----
From:   Albert Mok [SMTP:[log in to unmask]]
Sent:   Thursday, April 22, 1999 8:00 PM
To:     [log in to unmask]
Subject:        Re: [TN] Microetch depth measurement

Dear Vaughan,

It is a very good  brainstorming practice.  I appreciate very much.  But
how to measure the before and after (hi/low) to tell the etch depth.  Our
CMM can only measure up to 0.00001".  But the depth is 0.00001-0.00003.  We
need to consider the tolerance of the CMM as well which reflect the reading
accuracy.

_____________________________________________________________



At 06:00 AM 1999/4/22 -0700, Vaughan, Ralph H wrote:
>Hi Albert,
>
>I don't have a complete answer for you but in my normal keep-it-simple
>methodology, could you not take your copper surfaced control board, mask
>areas or patterns (stripes or checkerboard for example) on the surface,
then
>etch.  When you de-mask,   you will have adjacent hi/low surfaces that can
>be compared.
>
>Just a thought.
>
>Ralph Vaughan
>Boeing-Atlanta
>
>> ----------
>> From:        Albert Mok[SMTP:[log in to unmask]]
>> Reply To:    TechNet E-Mail Forum.;Albert Mok
>> Sent:        Thursday, April 22, 1999 4:40 AM
>> To:  [log in to unmask]
>> Subject:     [TN] Microetch depth measurement
>>
>> Dear technetters, good morning,
>>
>> Many board shops required microetch process, which is normal the
>> pretreatment/pre-cleaning of copper surface prior to subsequent chemical
>> processes. We have to control the etch depth, either from the spray
>> system,
>> or the batch wise bath from autoplating line.  The desired etch depth
>> varies from process for process but ranging from 20-50 microinch.
>>
>> We are using one sq. ft. bare board for the etch testing so that the
etch
>> depth is calculated when we based on the fact that 1 microinch is 0.02g
of
>> copper for one side.
>>
>> We hope to collect ideas or  to gain your experience for getting this
>> results more wisely.  We tried of weighing the board, etch, clean and
>> weigh
>> it again.  We are thinking to make some tools for this test so as to
make
>> the control more easily. We hope to plate copper at a control thickness
of
>> 30 microinch and use this as a specimen for the control test or to find
a
>> way telling the etch depth by co-relation.  We cannot consider the etch
>> chemicals condition since the batch wise and spray application are two
>> extremes.
>>
>> Please kindly offer your ideas and chat.
>>
>> ################################################################
>> 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's web site (http://www.ipc.org) "On-Line Services"
>> section 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's web site (http://www.ipc.org) "On-Line Services" section
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's web site (http://www.ipc.org) "On-Line Services" section for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################


ATOM RSS1 RSS2