Orbotech SPTS Xactix e1 Series, Руководство пользователя

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Manual Version e1-4.3.0.ae-R3. Page
62
5.3.8 Performing an Etch in the High Conductivity Mode
The operation of the e1 Series in the high conductivity mode (optional upgrade) is similar to the normal
mode; however in the high conductivity mode, there is the ability to flush the chamber between each
cycle with nitrogen. This flush cools the sample and also helps to flush effluents through the chamber
which often help improve etching selectivity and its screen is shown below:
5.3.8.1 High Conductivity Mode Etching Variables
Number of cycles
Since the e1 Series is primarily a pulsed xenon difluoride etching system, the duration of the etch is
controlled by the number of cycles. A cycle consists of the xenon difluoride sublimating to the set
pressure in the expansion chamber, etching for a set amount of time and evacuation of the main
chamber and expansion chamber. Note that there is a range button which changes the slider range for
selecting larger numbers.
Etch Time
When the valve between the main chamber and expansion chamber is opened the pressure
equilibrates and the etching process begins. The etch time is the time between the opening of the valve
between the expansion chamber and the process chamber and the opening of the valve between the
process chamber and the pump. Note that there is a range button which changes the slider range for
selecting larger numbers.
XeF
2
Pressure
In order to introduce the proper amount of xenon difluoride into the main chamber a set pressure
change of xenon difluoride must be delivered to the expansion chamber. Because xenon difluoride has
a vapor pressure of ~4T at room temperature the upper limit for the XeF
2
pressure is approximately 4T.