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minimize pump downtime, chamber contamination, and
thermal issues. In addition, these systems can incorporate
key application considerations like reduction of magnetic
fields.
Vacuum options available from Aerotech:
• Low Vacuum Option (10-3 torr)
• Standard Vacuum Option (10-6 torr)
• High Vacuum Option (10-8 torr)
Most Aerotech stage products are available with
modifications for either low vacuum (10-3 torr) or standard
vacuum (10-6 torr) use. Custom designs are available that
are certified to high vacuum (10-8 torr).
Material Selection
Because acceptable materials vary according to vacuum
level, application, operating temperature, etc., Aerotech
offers a broad array of options that control total mass loss
(TML) and collectible volatile condensable materials
(CVCM). For key design components, Aerotech does the
following:
• Lubricants: Low vapor pressure lubricants are selected to
be compatible with the vacuum level and the customer’s
process (e.g., elimination of hydrocarbons).
• Cable Management System (CMS): CMS construction
and materials typically utilize Teflon® insulated wires
(MIL-C-27500) along with specialized electrical connectors
that utilize a variety of materials including PEEK™. Other
cable and connectorization options are available depending
on the application requirements.
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• Surface Finish: Surface finish options include bare
aluminum, electroless nickel, or vacuum-compatible paint
(Aeroglaze Z306).
• Hardware: Systems use vented stainless-steel fasteners
for all blind holes and all potential air traps are vented.
Aerotech has always worked very closely with our
customers to ensure that the system meets or exceeds
outgassing requirements.
Thermal Management
Thermal management is key in vacuum systems because
they cannot rely on convection for the removal of heat from
the motors and bearings. Without thermal management
methods, stage performance and life can be reduced from
that of an equivalent system operated in atmosphere. This is
why Aerotech has put forth a considerable effort in the
development of thermal isolation methods and passive and
active cooling techniques. These techniques help to
maximize conduction modes of cooling and reduce or
eliminate heat sources inside the chamber.
Servomotors
Design of linear and rotary servomotors is critical to
vacuum system operation because they are the primary heat
source. This is why Aerotech designs and builds motors to
specifically address the issues associated with motors in continue, page 3
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