Short manual for Nova 200

Tips & tricks

The FEI Nova 200 Dual Beam system is equipped with a 30 kV SEM FEG column and a 30 kV FIB column with Gallium source.
There is also one Gas Injector System (GIS) for Platinum (Pt) deposition.
The SEM/FIB is controlled by two computers, one for real time image acquistion and process control, and one for further processing and general access to computer network.

The two computers have one mouse and keyboard that are connected to either one computer depending of which screen the mouse cursor is placed on.

 

Here is a view from the inside of the main vacuum chamber.
At the very left is the sample stage with the stub holder with a sample stub mounted.
At the top center is the angeled FIB column, and in front of that is the gas injector needle.
Next to the right is the vertical SEM column. Further to the right is the Everhart-Thornley electron detector and below that is the CCD-camrea with its surrounding IR-diodes for illumination.

 

How to mount a stub in the holder.
Of course it is necessary to use clean-room gloves when mounting the stub.

 

There is a small flexible pin pushing against the stem of the stub to ensure good electrical contact. Therefore there is a little friction when inserting the stub, even when the fastening screw is fully loosened.

Here is the chamber open during loading of sample, views from left and from right.


Most of the functions in the system are fairly fail-safe, but there is one procedure when it is quite easy to cause damage to the system, and that is when pushing in the stage, closing the chamber door after mounting the sample stub.

ALWAYS CHECK THE HEIGHT OF YOUR SAMPLE WITH THE MEASURING TOOL!

There is no protection against a too high sample being smashed into the lower end of the SEM-column when closing the chamber door. Replacement of a defect SEM-column cost about 20.000 Euro and requires about two weeks of service work.

BE WARNED!

The height measuring tool should always be placed on or close by the system. It must never be left inside the chamber!
If you cannot find the tool, please report to the person responsible for the system.

It is very good practice to watch the live CCD-camera image while closing the chamber door. The camera is mounted on about the same height as the end of the SEM column, thereby making it easy to judge if the sample might touch the SEM-column.

Another word of caution: avoid using lumps of magnetic material as sample! When using the SEM in high-resolution mode (immersion mode) there is a powerful magnetic field at the end of the SEM-comlumn.
This field is powerful enough to lift a lump of magnetic material and cause it to crash into the SEM column!

When you have safely closed the chamber door, you start pumping the chamber by clicking on the "Pump"-button in the upper right part of the computer screen. More on that in the next section.

It takes about four minutes to pump down the chamber.

 


The chamber door with the stage control knobs
for X-, Y-, Z- and Rotation of the sample stage.
The cylinder at the top left is the motor for the
tilt movment, there is no manual knob for that.

Controlling software (GUI)

All real time control and acqusition is done on the right computer screen. Below is a screen shot of the controlling software.

The software controlling the SEM/FIB Nova 200 is usually running in "Quad"-mode. This means that there are four quadrants that can display images collected from various detectors.

The standard setup is to use

Each quadrant is activated by clicking the mouse in it. Activation is indicated by the information field in the lower part of the quadrant getting blue instead of grey. In the screen dump above the upper left, SEM quadrant, is active.

The very right-most part of the screen shows status and parameters for the activated quadrant and column/detector combination.

In the above screen dump all quadrants are paused, indicated by the green pause symbol, except for the CCD-camera at the lower right. That means the the only quadrant showing a live image is the CCD-camera.

 


Some realtime controls can be manipulated from an external control. From left to right: image brightness and contrast, stigmator X and Y, magnification, beam shift X and Y, focus fine and coarse.

 


Here the FIB-quadrant, the upper right is activated, and the right-most part of the screen shows the parameters for the FIB column

Tips & tricks

Next chapter, details of GUI


Anders Liljeborg Nanostructure Physics, KTH.