Miguel,

our standard 4-layers DYCOstrate microvia substrates are about 0.2mm
thick (polyimide material). Each layer pair is about 50 microns thick.
For a 8-layer microvia build-up we get about 0.5mm.

In the DYCOstrate foil approach through-vias connect the central two
layers while staggered blind-vias connect the outer layers to the
central ones.
The microvias diameter can be down to 50 microns and pads down to 150
microns. Lines/spaces can be down to 50/50 microns.

Please contact me off-line for more info or have a look at our web site
for build-up description and applications examples.

Best regards,
Mike

> Hello All,
>         I am writing to ask if anyone has information on "ultra" thin PC
> boards.  For example, a four layer board with a thickness of about 0.5mm.
> We are currently looking for thinner board technologies, and are
> investigating several possibilities.  Any help is greatly appreciated.
> Thank you in advance.
>
> Regards,
>
> Miguel B. Galvez
> Engineering Technologist
> Hewlett Packard - Portable Capture and Communication

_____________________________________________________________________
Dr. Michele B. Stampanoni (Mike)      Phone:        +41  1 306 20 30
Manager Marketing & Sales             Fax:          +41  1 306 36 40
                                      Mobile:       +41 79 401 17 15
http://www.dyconex.com                E-mail: [log in to unmask]

DYCONEX Ltd.                          Unterwerkstrasse 3-5
                                      CH-8052 ZURICH
Advanced Circuit Technology           Switzerland
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