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:

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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

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