GA05141_0702 - 09/2004
Materials
Caution
Layers
Caution
9
Description
1.2
Compatibility with
pumped media
The MAG are specifically designed for the needs of the semiconductor
industry.
All materials used inside the pump are compatible with typical gases used
for semiconductor processes.
Please consult Leybold for recommendations on pump models for
specific processes and application requirements.
Corrosion protection
To protect the pump from corrosive gases it is mandatory to use dry
Nitrogen purge during operation of the pump.The purge gas protects the
bearing section and the motor from corrosive gases.
The rotor and the stator of the pump are KEPLA
®
-coated to prevent corro-
sive attack caused by the process gases. The corrosion protection of the
pump is effective only when the pump is protected from moisture during
standstill and storage. If the process gas contains moisture, contact
Leybold for recommendations.
Sublimation
Some media (e.g. AlCl
3
) can sublimate in the pump and form deposits.
Thick coatings can infringe on the required operating clearence and ultima-
tely cause the pump to seize. These deposits can also react with moisture
and generate corrosive gases (e.g. HCl).This can become very critical when
the pump is exposed to air. Deposits can be avoided in many processes by
heating the pump with TMS (Temperature Management System).
The TMS is integrated in all CT-versions. The purpose of the TMS is to keep
the pump temperature in a constant range. To achieve the temperature the
pump is equipped with a heaterband.
Some media ( e.g. metall organic compounds ) can decompose at the hot
surface of the pump and build layers. Please direct any inqueries to the
manufacturer.
In order to handle gases or media (e.g. AlCl
3
) which can form
deposits inside the pump it is required to use the TMS (Tempera-
ture Management System). The temperature selected for such
processes has to be set to the maximum value.
Ignition danger
During operation the pressure inside the MAG is so low that there is no dan-
ger of ignition (at pressures below about 100 mbar). A hazardous condition
will be created if flammable mixtures enter the hot pump at pressures
above 100 mbar. During operation the pump can reach temperatures as
high as 120
°
C (248
°
F). If the pump is damaged, sparks could occur which
could ignite explosive mixtures.
Also note the safety information provided by the gas supplier.
Purge gas
Summary of Contents for MAG 1500 CT
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