Harvey,

The industry tends to distinguish microvias by their
size rather than the method of manufacture.

6 mils (or 150um) is the generally accepted transition
point to a microvia.

Whether the via is formed by mechanical drilling, by
laser drilling or photo defined, it is still a microvia.

I prefer the term HDI (High Density Interconnect) to
describe this technology which includes smaller vias,
finer lines, smaller SMT pads, smaller pitch etc.

Please contact me if you need any more info.

Regards,

Brian McDermott
Director of Advanced Technology
MicroVia, Inc.
Winter Springs FL 32708 USA
Website : www.microvia.com
e-mail : [log in to unmask]
Voice (407)6995000x214  Fax 6996871
------------------------------------------------
-----Original Message-----
From: Harvey Monroe PHILLIPS <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Monday, April 05, 1999 11:30 PM
Subject: [TN] Definition of Microvias


>Dear TechNetters,
>
>I have a question about the usage of the term "microvia".  Does it refer
>specifically to vias (either blind or through) in a build-up layer or does
>it refer primarily to the size of the via (say blind or through vias with
>diameters less than 150 microns)?
>
>Thanks,
>Harvey Phillips
>
>Research Fellow
>Microelectronic Materials and Packaging Group
>INSTITUTE OF MATERIALS RESEARCH AND ENGINEERING
>TEL:    (+65) 872 7545
>FAX:    (+65) 872 7528, (+65) 872 0785
>e-mail:  [log in to unmask] <mailto:[log in to unmask]>
>
>Block S7, Level 3
>National University of Singapore
>Singapore 119260
>
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