Jason;
I can not agree with Don any more.
One more thing I want to point out is about processibility.
CEM-1 is punchable. On the other hand, one has to use drill for FR-4.
The processing speed is much faster for CEM-1, which is one of critical factors for mass
production. In your case, I think CEM-3 is the choice as Don suggested since the product
has to go through IR-reflow process. CEM-1 has been used for the reflow process in a
limited bases, as far as I know. Therefore, it may be feasible but is very difficult, I think.
CEM-3 is punchable as well as cheaper than FR-4.
We, Doosan Electro-materials, offer a variety of quality base materials including FR-1, FR-2,
CEM-1, CEM-3, and FR-4 at competitive price.
If you are interested, please call Mr. Kim who is our US office manager at 408-865-1636.
Minsu Lee
Associate Manager
R&D Dept.
Doosan Electro-materials Co.
----- Original Message -----
From: Don Vischulis <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, May 21, 1999 7:58 AM
Subject: Re: [TN] Substrate questions
> Jason:
>
> CEM-1 is a laminate with a random cellulose fiber core, woven glass adjacent to the outside, and a
> difunctional epoxy resin. FR-4 covers a multitude of laminates. The common factors for the FR-4 family
> include woven glass through the laminate and an epoxy resin which may be difunctional or multifunctional.
> CEM-1 usually utilizes a low Tg resin while the FR-4 family can cover the Tg range from 110 to over 200 C.
>
> In general, most applications for with plated through holes utilizing CEM-1 have resulted in disappointing
> results due to a large Z-axis expansion. If you require low cost and plated through holes (2 layer
> product) you might want to investigate CEM-3 which is a random glass fiber core with woven glass near the
> copper and an epoxy resin.
>
> Don Vischulis
>
> Jason Smith wrote:
>
> > Fellow Technetters, Does anyone have any experience with CEM -1 vs. FR-4? What
> > exactly is CEM1 and it's differences to FR-4? What reliability issues need to
> > be addressed? A customer is looking for a cost savings on a high volume,
> > scarcely populated product. There is only one IC on it that may need to be glob
> > topped or underfilled to handle the CTE of a different type of substrate.
> >
> > Jason Smith
> > Process Materials Engineer
> > Lexmark Electronics
>
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