INFICON UHV Bakeable Sensor - Manual (Page 24)

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UHV Bakeable Sensor Operating Manual
2.1.4 Sensor Shutter Check
Temporarily connect an air supply to the actuator air tube fitting on the feedthrough.
Use the manual override button on the solenoid valve (see
Figure 3-2 on page 3-4 ),
or other means, to activate and deactivate the pneumatic shutter several times.
NOTE: The air supply must be 70 psi (gauge) {85 psi (absolute)}
(5.8 bar (absolute) [584 kPa (absolute)] (minimum) to 80 psi (gauge)
{95 psi (absolute)} (6.5 bar (absolute)) [653 kPa (absolute)] (maximum).
WARNING
Do not exceed 100 psi (gauge) {115 psi (absolute)}
(7.9 bar (absolute)) [791 kPa (absolute)].
Connection to excessive pressure may result in personal
injury or equipment damage.
When activated, shutter movement should be smooth, rapid, complete, and the
shutter should completely expose the crystal opening. When deactivated, the
shutter should completely cover the crystal opening. Repositioning of the shutter
may be required to achieve optimum positioning. To adjust the position of the
shutter on the shutter shaft, loosen the socket screw on the shutter assembly,
rotate the shutter to the desired position, and tighten the socket screw.
NOTE: A Solenoid Valve (PN 750-420-G1) is required for a shuttered sensor
installation. See Chapter 3 for more information on the Solenoid Valve
and its installation.
2.2 Sensor Installation Guidelines
Install the sensor as far as possible from the evaporation source (a minimum of
25.4 cm or 10 in.) while keeping the sensor in a position well within the evaporant
stream to accumulate thickness at a rate proportional to accumulation on the
substrate.
Figure 2-2 on page 2-6 shows proper and improper methods of installing
sensors.
Plan the installation to ensure that there are no obstructions blocking a direct path
between the sensor and the source.
For best process reproducibility, support the sensor so that it cannot move during
maintenance and crystal replacement.
Figure 2-1 shows the typical installation of an INFICON UHV Bakeable Sensor in
the vacuum process chamber. Use the illustration and the following guidelines to
install sensors for optimum performance and convenience.