Category:PCB PCB Pad

Group Administrators: 1 | Group Member: 21 | Group Threads: 20

Pad cratering is a mechanically induced fracture in the resin between copper foil and outermost layer of fiberglass of a printed circuit board (PCB). It may be within the resin or at the resin to fiberglass interface. Do you have ever problems about pcb pads? please talk here.

Thread Reply
Bare Copper Pad Reflow Soldering Reply 2017-02-27 07:06:38
375 views
5 comments
17 likes

tom

Leave A Message

Follow

I received a request from customer to assemble ceramic substrate (alumina oxide)that printed with a low temperature Copper thick film conductor (the overglaze layer is polymer). The Copper pads are exposed without any coating. This ceramic substrate went through double sided reflow in N2 environment(around 100units of SMT components on each side), followed by the third time hot-bar reflow for lead-frame pins assembly at the 2-edges of the ceramic. The Proto-run result showed that the exposed Copper pads were partially oxidized after 2nd time reflow. Hence, the 3rd time reflow couldn't form acceptable joints. I'm thinking of using OSP technology to prevent/minimize the oxidation from happening especially during 1st & 2nd reflow. Would appreciate any suggestion/comment to prevent/minimize oxidation on bare copper pads.
17 likes
Statement: This post is only the personal view of the author and does not represent the opinions of ALLPCB.com.

hakan kaynar

Leave A Message

Follow

I will keep on reading your sharing. Thats really interesting and helpful.

Thomas Lithen

Leave A Message

Follow

What you share on your post is quite useful.

Roberto Ross

Leave A Message

Follow

very useful informations.

M.?Aznar

Leave A Message

Follow

Like this post very much.

IngeniApp

Leave A Message

Follow

I have truly impressed by your post. Please keep us up to date like this.
ThreadReply