Q150T Sample Preparation System
Q150T - Instruction Manual
29
10473 - Issue 5
5.1.3
Aluminium thin film
Aluminium is often difficult to coat due to its fast oxidizing properties. Also, its oxidized
layer is difficult to remove as it reduces the required target voltage to produce a sputter
current of 150mA. This increases the time required to clean the target.
However, the Q150T is set up to cycle the plasma which reduces this cleaning time. The
cleaning cycle is terminated when the target voltage rises above 300V, thus preventing
an already clean target coating the chamber excessively.
As an example, to achieve an Aluminium coating of 100nm:
1.
Create a new profile based on
QT FTM Terminated Sputter
.
2.
Edit the newly created profile.
3.
Set the material to
Aluminium
.
4.
When prompted, select
Use material defaults
. This applies a sputter current of
150mA to clean the target.
5.
Edit the
Terminate thickness
setting to 100nm.
6.
Tap on the
OK
button to close the Editor.
The clean time in the
System
properties should be between 10 and 30 seconds.
However, leave at the default value of 30 seconds for this setup. The Q150T applies the
optimum parameters for the cleaning cycle appropriate to your selection in the material
list (in this case, aluminium).
On running the above process the coater will:
1.
Pump down to the clean stage as before.
2.
Clean the target for the time specified by
clean time
in the profile.
3.
Wait for 20 seconds with the plasma off.
4.
Repeat the procedure until the target voltage is above 300V at the end of the
clean cycle for two consecutive cycles.
5.
Continue with the standard sputter cycle.
If the target voltage fails to reach 300V after 15 cycles (see note below) the process is
stopped automatically. This might occur if the target has not been used recently. Vent
the system, remove the target and clean it manually using a fine abrasive. Repeat the
process.
The maximum of 15 cycles is determined by the
Max pulse clean cycles
property in Generic Sputter parameters
(see page 45). Note
administrator level access is required to change this property.
Summary of Contents for Q150T S
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