A blog on the repair, operation and calibration of surface analysis systems and components including electron spectrometers, sputter ion guns and vacuum related hardware. Click on the Index tab below to see a list of all posts. Visit our website at http://www.rbdinstruments.com
RBD has released Version 1 of CMapp – the data collection, analysis and control application for the microCMA. Of course, this is not the first version of CMapp available, but we had a set of features in mind for Version 1 that would truly represent the most feature-complete version of CMapp. Of course, this won’t be the last version – we’re already busy adding new features and working on a completely redesigned application for a future release.
The key new feature in CMapp 1.0 is the addition of the Electron Gun Control Pane, which replaces the dialog window. All of the electron gun controls are always available on-screen in the familiar layout. There’s no longer a need to move or minimize a window in order to view acquisition data.
Other Features and Changes
CMapp now offers the ability to differentiate and smooth data while acquiring. This is invaluable for getting important peak information in real-time, and removes the need to wait until the end of an acquisition to determine if the parameters are resulting in useful / expected data.
The latest version of CMapp also includes the ability of the edit the Wehnelt setpoints in the Hardware properties menu. Normally these values are factory set, but now they are easier to adjust without putting undo “stress” on the filament by ramping the beam voltage from 2 to 3 kV before having ballpark Wehnelt values.
Lastly, some minor changes have been made to improve the UI when working with Windows 11.
We have added a few new features to CMapp, our microCMA acquisition and data massage software.
For example, when you first open the electron gun dialog box, a filament warm-up reminder pops up:
It is recommended that you warm up the filament at the beginning of each session so that the microCMA can thermally stabilize. The filament warm-up routine brings the filament current up over a 5-minute period and then keeps the filament on. What is nice about this feature is that you can just click “Yes” and then walk away and come back later when you want to use the microCMA.
Another new feature is the “Auto Set the Beam Voltage
to 2 kV ” for alignments:
The alignment acquisition is typically used to acquire a 2 kV elastic peak that sets the analyzer to the sample distance. Surveys and multiplexes are typically acquired with the beam voltage set to 3 kV. Then, if you move to a new sample, or if you move the same sample to a new location, you would need to re-acquire a 2 kV elastic peak. With the “Auto Set beam to 2 kV” feature, you can just acquire the elastic peak alignment and the beam voltage will automatically change from 3 kV to 2 kV.
The new Diff/Smooth feature combines the differentiate and
smooth commands into one click:
Related to the Diff/Smooth command is the ability to
automatically Diff/Smooth at the end of an acquisition:
By checking the “Auto Diff/Smooth After Acquisition” box, the data will automatically differentiate and then smooth when the acquisition is complete. The “Auto Diff/Smooth” feature works for surveys, multiplexes, and alignments. Since you need to differentiate the data for quantification anyway, you might as well have it happen automatically.
Finally, we have added a feature that provides estimated
target current. This is helpful if your target is grounded internally on your
sample manipulator and you have no way to measure the actual electron beam
current. Rather than using the emission current to set the relative target
current, you can use the estimated target current to set the electron beam
current to the recommend 300 nA.
First, select Estimate Target (Beam) Current in the Hardware
Properties dialog box:
The estimated target current will be displayed in the Electron Gun dialog box as shown below:
Each electron gun filament behaves a little bit differently so the user-settable Emission Current-to-Target Current ratio can be adjusted in the Hardware Properties dialog box. We will have a video soon that will show you how to set this ratio.
If you have our 9103 USB picoammeter or some other picoammeter, you can measure the target current and enter the value into an acquisition manually (or, in the case of the 9103, automatically). You define this setting in the Hardware Properties dialog box.
If Estimate Target Current is selected, then the estimated target current will be entered into the acquisition before the acquisition starts. Whether entered manually, automatically, or estimated, the target current is displayed on the left-hand side of the alignment, survey, or multiplex acquisition.
For more information on our microCMA compact Auger Electron
Spectrometer visit our website:
RBD Instruments’ microCMA compact Auger electron energy analyzer is designed to fit on a standard 2.75″ / 70 mm CF flange. This makes it possible to add surface sensitive AES (Auger Electron Spectroscopy) to an existing vacuum chamber, as long as there is an available port.
The standard length of the microCMA analyzer is 11.1″ / 283 mm which works well for most 8″ / 200 mm diameter vacuum chambers. This standard length factors in a Z translator that is used to move the microCMA to the sample for analysis and to retract the microCMA when it is not in use.
However, what if your flange-to-chamber distance is much longer or much shorter than the standard length? There is a 4.5″ / 114 mm limit on how short the microCMA can be due to the geometry of the analyzer section. For longer flange-to-target distances, the analyzer section can be extended as needed. The photo below shows a short 5″ microCMA and a long 21″ / 533.4 mm microCMA.
No matter what your flange-to-target distance is, if you have a 2.75″ / 70 mm flange available, it is possible to add the surface-sensitive analytical AES technique to your chamber. The microCMA and Auger Electron Spectroscopy are especially useful for MBE chambers and other research experiments that deposit thin films and where surface-sensitive elemental analysis is required.
For more information on the microCMA visit RBD Instruments’ website here – microCMA
