
5.TROUBLESHOOTING B-70265EN/02
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No. Check item Cause of trouble, Solution
6 Checking the
laser gas
1) Check whether the laser gas composition is
correct, and replace the laser gas with the one
that satisfies the specifications.
2) Check for gas leakage in the external laser gas
piping, investigate the faulty location by
referencing Chapter 3, and correct the external
piping.
3) Investigate the faulty location to check for
leakage inside the oscillator, and replace the
faulty part.
7 Checking the
cooling water
Check that the cooling water temperature is within
the range from 20 to 30°C.
The amount of water supplied to the power supply
may have decreased. Check whether the piping is
clogged, and take appropriate action.
8IF PCB
abnormal
Replace the IF PCB.
9 Pressure
sensor
abnormal
Replace the pressure sensor.
10 Checking
cable
connectors
Check for looseness in the cables and connectors
connected to the power supply, matching box, and
discharge tubes.
11 Insufficient
discharge
aging
See the description of automatic aging in (1) in
Subsection 3.3.6, and perform aging.
(2) Confirming operation and investigating the cause of a fault
Switch on the failing power unit, observe the condition and
clarity the cause referring to the following tables.
No. Phenomenon Presumption cause
1 An alarm is issued when the LED of a
laser power supply unit is not turned on.
The IF PCB is faulty.
Poor cable contact
2 An alarm occurs before discharge begins.
(The time when 200 VAC is supplied to
the power supply)
The laser power supply
is defective.
3 The RF current is small in comparison
with other power supply units and the
discharge tends to disappear. (DCI alarm)
4 The RF discharge current is large in
comparison with other units. The alarm is
DCV alarm.
The laser power supply
is maladjusted.
5 The RF voltage of all the units is high
during discharge and the laser power is
low. The discharge tends to disappear.
(DCI alarm)
When the purge is repeatedly performed,
the RF voltage gradually decreases and
the laser power recovers.
This phenomenon often appears after the
laser was not used for a long period.
The external laser gas
pipe is abnormal.
The gas composition is
not normal due to
leakage of a gas.