Interactive exhibit · Focused ion beam · Dual beam FIB-SEM
Sculpting with Ions
A working dual-beam microscope: an electron beam to see, and a beam of gallium, xenon, argon, nitrogen or oxygen ions to cut, polish and build. Every image, trench and pattern is computed from the physics. Click any label on the instrument for the physics behind it.
Click a label on the instrument for its physics card: how it works, typical specifications, how it is calibrated, and live values. Drag the 3D view to orbit, scroll to zoom.
Modes (keys 1–9, 0, -, =, and \ for the cryo lamella): the electron beam (SE, in-lens, BSE, EBSD, TKD, EDS), the ion beam (ion image, mill, deposit), workflows (slice & view, lamella, cryo lamella) and the Monte Carlo of electrons or ions. Space pauses, C clarity, L labels, R resets the view, N narration.
Ion species: gallium from a liquid-metal source (the finest probe) or xenon, argon, nitrogen and oxygen from a plasma source (microamps of current, no gallium). Compare their milling rates, damage depths and chemistry.
Mill and deposit: drag on the ion image to draw a pattern (rectangle, regular or cleaning cross-section, line, circle), then press Start. The electron image beside it watches the trench grow at 52°. In Deposit mode, choose Pt, C or W and the electron or ion beam.
Lamella: run the eight steps of a TEM lift-out, then thin the lamella yourself at decreasing currents and polish it at low kV. Slice & view: serial-section a battery cathode (or high-pressure-frozen yeast, on the cryo stage) and segment its phases.
Cryo lamella: yeast cells frozen in vitreous ice on a grid, on a −190 °C stage: sputter coat, cold GIS platinum, a grazing milling angle and relief cuts, then mill both sides down to ~200 nm for cryo-electron tomography, without warming the ice (it crystallises) or letting contamination grow.
Control panel: press V for the on-screen console (Q/W focus, A/S magnification, Z/X beam current, H/L and K/J multifunction, O/P context, arrows for the stage, Tab for stigmator / beam shift / tilt & Z / pattern size, U to start or stop patterning). The TEM-view Console or any game controller works too; the knobs follow the active beam.
AI mode (brain button or /): type commands like “switch to xenon”, “mill a cross-section”, “deposit 1 micron of platinum”, “thin to 100 nm”, “what is the sputter yield?”. Hold M to say them. Connect an AI agent (tools/fibview-mcp) to answer questions and run the instrument with you.
Training (T): focus the SEM, focus the ion beam without destroying the sample, find the eucentric height, thin a lamella to 100 nm. With your consent the session is recorded (no personal data) and can be downloaded, replayed, or shared with a Hugging Face research dataset.
Python (P): script the instrument with the fibview package, in the browser or on a desktop.
What is computed, and how
Images of both beams are ray-cast through the current surface, so a tilted view sees the faces and walls of milled trenches. Electron images use the SE yield curve and secant law, SE2 from backscattered electrons, Reuter/Arnal η(Z, tilt), channelling, ETD shadowing and the probe budget. Ion images use kinetic ion-induced SE emission (∝ electronic stopping), secondary-ion yields enhanced by oxygen, ion channelling, positive charging of insulators, and the ion probe (source, chromatic and spherical terms, with tails).
Milling removes J·Y per step: sputter yields from measured Ga 30 kV volume yields, scaled to other ions and energies with Sigmund's theory and ZBL nuclear stopping, with Yamamura's angular dependence, channelling, gas chemistry (XeF₂, H₂O, oxygen ions on carbon), redeposition and wall taper. Deposition follows reaction- and precursor-limited regimes minus sputtering. The ion Monte Carlo is a binary-collision code (ZBL potential with a tabulated scattering integral, Lindhard–Scharff electronic stopping, full recoil cascades and surface-binding sputtering). EBSD/TKD, EDS (now with implanted Ga, Xe, Ar) and the electron Monte Carlo are as in the SEM exhibit.
Simplifications: patterns run one at a time with an averaged dose; curtaining and redeposition are modelled phenomenologically; the lamella's thinning passes use a geometric model. Trends, length scales, rates and damage depths are right; absolute signals are illustrative.