INFICON STC-2002 Thin Film Deposition Controller Operating Manual - Manual (Page 34)

p STC-2002 DEPOSITION CONTROLLER y
SECTION 2.XX e page 32 of 276 ^
higher temperatures than the teflon cable of the standard configuration). The ends of the water pipes and
crystal connection are on the other side of the thick metal disc (places the 3 terminations outside the
chamber). The electrical connection is terminated with a standard male BNC connector. The "bakeable"
unit, therefore, presents itself on the outside of the flange like the standard crystal sensor. The so-called
"Dual Shuttered Head" has 2 crystal sensors in tandem on a single assembly. As part of the assembly, a
shutter always covers one crystal while exposing the other. When the shutter moves it exposes the
formerly covered crystal and covers the formerly exposed crystal. The installation of a dual shuttered
sensing head is similar to that of the single head. A second sensing input (Sensor 2) is used on the second
crystal channel. (If other Sensor cards are installed, a second sensing input could be selected on these.)
Automatic crystal switching by shutter is accomplished by I/O programming. The primary crystal sensor
channel (Channel 1 in this example) has an associated shutter control bit weight value accessed through I/O
programming (ID#81). The primary crystal sensor channel (Channel 1 in this example) and the secondary
crystal sensor channel (CH
annel 2 in this example) are set to the active state by menu programming. By
opening or closing the shutter associated with the primary crystal sensor channel (Channel 1 in this
example), the I/O programming performs the necessary functions for controlling the shutter of the dual
sensor. Proper phasing between the sensor inputs and shutter control can easily be checked by installing a
sensing crystal in only sensor 1 and observing the good and "failed" (absent) sensing crystal when
switching manually between sensor 1 (good) and sensor 2 (failed).
Of course this mechanical method can be supplemented by using 2 sensors without shutters. The primary crystal sensor channel
(Channel 1 in this example) and the secondary crystal sensor channel (CH
annel 2 in this example) can also be selected by I/O
programming commands or the active sensor can have a backup crystal sensor channel list that names channel 2 (or the secondary
sensor channel) as the automatic replacement for the failed primary channel. (Sequence would be: fail primary [by command or 3
rd
STATUS menu], backup list provides secondary, re-verify [by command or 3 rd STATUS menu] reinstates the primary.)
Power Supply Connection: This refers to the high current (or voltage) power supply that provides the
energy to create the evaporant stream. The power supply connection on the STC-2002 has the control
voltage that controls the high current (or voltage) power supply. From the STC-2002 point of view, this is
known as the source control voltage. The word source describing the source material of the deposition
process in the form of an evaporant stream. Along the bottom of the back panel, in the area where sensor
cards may reside, is the text label SOURCE. This is meant to indicate the 9 pin D-sub connector that is part
of the sensor card. The text labels ½, ¾, 5/6, 7/8 refer to control voltage outputs. In the first sensor card
slot, this indicates control voltage 1 and control voltage 2. Control voltage 1 is meant to control the high
current (or voltage) power supply just described. The 2
nd control voltage is typically used for the strip chart
recorder control. These identical analog outputs can be interchanged. In fact, their function is assigned by
means of menu programming. If the two functions (control voltage and recorder) are assigned by menu
programming on the same analog channel, the control voltage will have precedence and the recorder
function will be lost. After these programmed outputs are used in a film, a conflicting recorder function
having been lost in this way would require a reboot to recognize a correcting change. The analog output
used for the control voltage output has a number of programmable parameters associated with it. One in
the MAIN/ REVIEW FILMS menu path is: SS MAP SELECT. Another one in the MAIN/ REVIEW MAPS
menu path is: source out channel. Don't overlook the ground connection (connector shell). Shielding goes
a long way toward noise reduction and ultimately contributes to a stable system. [Section 4.6X has more
details]
Strip Chart Recorder Connection: This refers to the STC-2002 output from the 9 pin D-sub on a sensor
card that can provide the proper analog signal for a strip chart recorder. Along with the hardware
connection, the analog output used for the strip chart recorder has a number of programmable parameters
associated with it. Two in the MAIN/ EXEC/ SYSTEM CONFIG menu path are: recorder function I/O
control and recorder out channel. Don't overlook the ground connection (connector shell). Shielding goes
a long way toward noise reduction and ultimately contributes to a stable system. (See Power Supply
Connection above) [Section 4.7X has more details]
RS232 Communications Connection: Located in the approximate center of the back panel and labeled
with the text RS232 is a male 9 pin D-sub connector for the purpose of communications with a PC or