From rcrane at snf.stanford.edu  Wed Feb 26 14:53:58 2003
From: rcrane at snf.stanford.edu (Dick Crane)
Date: Wed, 26 Feb 2003 14:53:58 -0800
Subject: Litho temp and Humidity control on 3/8/03
Message-ID: <3E5D4586.4A112776@snf.stanford.edu>

Litho users,

On Saturday, March 8, the HEPA air shut down in the Nikon aisle will
affect local temperature and humidity control, which will affect the PR
quality from the SVG coater and resolution on the Nikon body 4, the
Ultratechs, and the EVG aligner. See details below.

Facilities will be upgrading the HEPA fan drive control units. This
upgrade will affect the quantity of air blowing through the HEPA filter
which will affect the airborne, particle count in the fab. Local area
volume of air will drop to 20% of normal flow. I would estimate that our

class 100 cleanroom will become a class 1000 room for a few hours. The
air is clean, but the room's ability to deal with particle assaults is
reduced. Processing which is very sensitive to particle contamination
should be avoided in the affected areas during the upgrade work.

Photo area: On Saturday, March 8, from 0700 to 1100, L102, the Nikon
aisle (Nikon body 4, Ultratechs, EVG aligner and bonder, SVG coat and
develop tracks) will have reduce air flow. This loss may be critical to
your process.

Mask making area: On Saturday, March 8, from 1200 to 1600, L106, the
mask making room (Micronic, AFMs) will have reduce air flow. This loss
should not affect your process. Wet bench exhaust will be unaffected.

Thanks for your patience,

Dick