Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

----- Original Message -----
From: "DJ Delorie" <dj@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, November 05, 2007 2:34 AM
Subject: [Homebrew_PCBs] Breaking the 6/6 barrier


>
> I seem to be seeing a trend here, that regardless of the techniques
> used, with care one can get to 6/6 rules. How do we get past that?
> It must be possible in theory, as the big fabs do it.

They must find it quite tricky, though, as my favourite supplier, PCB-Pool,
doesn't go below 6/6, and some don't even go below 8/8, like Olimex.

They use negative resist, which gives better definition, and thinner copper
(I think they only offer < 6/6 on multi-layer boards). They also use much
higher artwork resolution than we can achieve, with vacuum keeping it in
contact with the resist, and highly collimated UV.

Leon
--
Leon Heller
Amateur radio call-sign G1HSM
Yaesu FT-817ND and FT-857D transceivers
Suzuki SV1000S motorcycle
leon355@...
http://www.geocities.com/leon_heller