Andy, we normally do not put solder mask between surface mount pads on
20 and 25 mil pitch. We just have a continuous window around all the
pads on each side of the part. You really do not need solder mask
between the pads as long as there are no traces between the pads.

Nick Wander
Unisys, Roseville, MN 

>----------
>From: 	Andy[SMTP:[log in to unmask]]
>Sent: 	Wednesday, March 12, 1997 7:38 PM
>To: 	'Technet'
>Subject: 	Solder Mask on fine pitch SMT component
>
>Hello
>
>I am facing a problem with fine pitch SMT component of 20mils. How can the
>soldermask be applied in between the pads without covering them? My supplier
>claims that their process capability is restricted.
>
>Another Question:
>Which PCB manufacturing house in Singapore can produce 6mils trace/air-gap
>(for internal layers as well) specifications?
>
>
>Please Advice...Thanks
>
>

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