Time-Resolved Focused Ion Beam Microscopy: Modeling, Estimation Methods, and Analyses

Mitigating Current Variation in Particle Beam Microscopy

“…In Figure 5b of [8], we can see that the bias of η TRML is very small, even when comparing against other TR-associated estimators. Using this fact to assume that η TRML is unbiased, this means that σ 2 γ = MSE( η TRML ).…”

“…which can be performed using a grid search. While the QM and LQM estimators are independent of λ, the TRML estimator proves to provide the most accurate image in reconstruction quality [8], [11]. For all of my tests, I will be using the meansquared error (MSE), as it is the accepted error metric for image accuracy.…”

“…Lastly, the inverse transform is applied, giving the resulting image. Next, there is η TRML (8), which neglects the current variation and uses λ, but proves to still be robust to this variation. The last method the new algorithm compares against is η oracle , which is η TRML (8) with perfect knowledge of the current variation and uses λ.…”

“…For this reason, I will be analyzing both HIM and SEM with a common abstraction, for values of secondary yield representative of each [7]. Lastly, although indirect electron detection is more common today, my work assumes direct electron detection since it offers higher signal-to-noise ratio and has been applied to improve imaging resolution in transmission electron microscopy [8]- [10].…”

Addressing Neon Gas Field Ion Source Instability Through Online Beam Current Estimation

“…), time-resolved methods have been shown to greatly mitigate the effects of source shot noise [5,6]. Additionally, when beam current is imperfectly known, timeresolved estimation methods exhibit a natural robustness to striped artifacts [3,4].…”