Well,
        I have only seen this problem at the high PPM level with 0402's.  It
was caused by capacitance plates being exposed through the side of the
capacitor.  Solder would attach to the end of the plate and allow solder to
bridge the gap between the two pads.  If you are seeing the same thing, 10%
of the caps having this problem is certainly high enough to complain
bitterly to your supplier.

Thanks

Ryan Grant
Advanced Technology Engineer
MCMS
(208) 898-1145
[log in to unmask]


> -----Original Message-----
> From: tangweidong [SMTP:[log in to unmask]]
> Sent: Thursday, June 15, 2000 8:18 PM
> To:   [log in to unmask]
> Subject:      [TN] 0805 SMD capacitor bridging  problem
>
> Recently  we have a module that have more capacitors smaller than 0805
> need to pass wave soldering,   After wave soldering we found about 10%
> capacitors bridging there . A bridge formed between two leads of the same
> component on the top of the it. We tried to supply more flux and the
> bridging reduced. But more flux is harmful  for clean and  reliability.So
> what is the fact.... We suppose the ceramic interface of the capacitor was
> not well  handled. The ceramic interface can be stained with solder
> because of less surface tension.
>
> We expect your advice.Thank you!
> Well . Don
> Huawei  R&P lab
> Shenzhen Science and Technology Park
>
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