CENTROTHERM E1200 HT 260-3, Руководство по эксплуатации

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E1200 HT 260-3
3BFunctional Description
23.04.07
4-12
00401010_41087
Figure 4-9: Components of the TEOS Cabinet
1 mass flow controller 5 nitrogen supply line
2 pneumatic valve TEOS bubbler 6 process gas line for process tube
3 TEOS bubbler 7 valve for process gas line
4 nitrogen valve 8 valve pump line
The TEOS bubbler has a supply of liquid TEOS.
Inside the bubbler, the TEOS is steadily heated at a temperature of 50 – 70° C to
vaporize it. Once heated, the TEOS is a process gas which is conducted to the process
tube via mass flow controller and valve.
A heating jacket is used to heat the entire process gas line from the pneumatic valve of
the TEOS bubbler down to the process tube. The part of the process gas line which
runs to the nitrogen valve is also heated. The temperature of the process gas line is
raised in three steps from the TEOS bubbler to the process tube to prevent
condensation of TEOS.
Nitrogen is used to purge the process gas line after every TEOS process to avoid
having residual TEOS in the process gas line or in the mass flow controller.
The TEOS cabinet is connected to the TGA toxic gas exhaust, so that the TEOS gas
can be exhausted in case of disturbance.
Sensors in the TEOS bubbler check the fluid level within the bubbler. If the process gas
in the bubbler drops below a certain level, a warning message is displayed on the
operating panel. For further information on the TEOS bubbler, please refer to the
suppliers' document on the bubbler, see chapter 12.10 Suppliers' Documents,
page 12-4.