Hi,
I'm running CASINO v3.3 and consistently getting an empty/blank Intensity Scan result (0.00–0.00 color scale, Backscattering Coefficient: 0, Secondary Yield: 0), even though everything else in the simulation appears to be working correctly. I've tested this across multiple independent projects, so it doesn't seem to be a corrupted file issue.
Setup:
- CASINO v3.3
- Sample: Si cube, tested at multiple sizes (300×300×300 nm and smaller 100×100×100 nm), centered at origin and repositioned so the top surface sits at Z=0
- Beam energy: 5 keV
- Number of simulated electrons: 1000
- Physics models: standard Monsel defaults (Total/Partial Cross Section: Mott by Equation, Browning [1994]; Random Number Generator: Lagged Fibonacci; Directing Cosine: Lowney [1994]; dE/dS: Joy and Luo + Lowney [Monsel]; Ionisation Potential: Joy and Luo [1989])
What works:
- Running a single-point trajectory simulation (Simulation → Start, viewing the 3D trajectory display) gives correct results: I can see elastic/inelastic scattering inside the cube, and the status bar shows non-zero Backscattering Coefficient and Secondary Yield.
What doesn't work:
- Running the "Intensity Scans" node (Microscope and Simulation Properties → XY Scan, e.g. -22 to 22 nm range, 1 nm spacing, ~1684 points) always returns a blank map with 0.00 for everything, and Backscattering Coefficient / Secondary Yield both read 0 in the status bar after completion (Progress reaches 100%, elapsed time is non-trivial, e.g. 2:31, so it does appear to run).
- In "Intensity Graph Properties," the correct region (Box_0 Inside) is checked, and "Backscattered Coefficients" is selected as the signal to display.
- I've tried:
- Unchecking "Conserve Data For Each Simulated Points (Distributions)"
- Correcting the Z focal point to match the actual top surface of the sample
- Disabling the ADF Sensor
- Increasing simulated electrons to 1000
- Creating a brand-new simple project (small cube, 3×3 scan grid) — same blank result
None of these changes the outcome; the Intensity Scan always comes back empty.
Is this a known bug in 3.3, or is there a step in setting up/triggering the scan simulation that I might be missing (e.g., a specific way to "activate" scanning mode vs. point mode before running)? Happy to send my .sim file if that helps debug.
Thanks in advance!
Hi Paula,
When running intensity scan, the results for each scan points is not saved. You need to select the correct Intensity Display->Intensity Distribution Display Options and you should see an image.
If it does not work, add the .sim file in your post and I will look at it.
Regards,
Hendrix
Hi Hendrix,
Thanks for the reply. I checked Display → Intensity Display → Intensity Distribution Display Options as you suggested — the correct region ("Box_0 Inside") is checked, and I tried both "Backscattered Coefficients" and "Secondary Electron Coefficients" as the signal. Unfortunately the map still comes back blank (0.00–0.00) and Backscattering Coefficient / Secondary Yield both read 0 after running the scan.
I've attached my .cas project file (my version saves as .cas rather than .sim), you can find it in the original post. For reference, this is a Si cube (300×300×300 nm, also tested at smaller sizes), 5 keV, 1000 electrons per point, standard Monsel physics defaults.
Let me know if you need anything else to debug it.
Thanks again,Paula