Deposit the library
Co-sputtering from several targets grades a controlled composition spread across one 100 mm wafer.
Combinatorial thin-film libraries
Rank a whole family of materials in one experiment.
xemx makes 342 different compositions in a single deposition run and measures every one. One run tells you which composition to carry into your own test plan, and which to rule out.
Work spans semiconductor and packaging, hydrogen and electrochemistry, extreme environments, RF and magnetic films, superconducting films, and implantable coatings.
Wafer map 100 mm library
The same library points to different regions depending on which property you measure.
What we do
Every composition is made under the same conditions.
xemx is a Ruhr-Universität Bochum spin-off. Every spot comes from the same run, so when one part of the wafer behaves better, that is the film talking, not the gap between two runs.
One deposition replaces hundreds of separate samples.
Lineage
The library method and its data tools come from Alfred Ludwig's group at RUB. The droplet cell and cell microscopy used to screen the libraries come from Wolfgang Schuhmann's group there.
Lars Banko worked on both sides, often on the same papers, for several years before founding xemx.
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Deposit the library
One run, several targets, a graded spread of compositions across the wafer.
How it works
From hundreds of compositions to one film you can test.
Map against position
XRD for structure, EDX for composition, and a probe for the target property, all mapped to the same wafer positions.
Read the landscape
The map shows where the target property improves and which regions to rule out.
Reproduce off-gradient
The chosen compositions are made again as uniform films, the same all the way across. Off the gradient, in other words: one composition everywhere instead of a spread.
Ready for validation
The uniform film goes to a fab, supplier, or partner for the next test.
Where to start
Three ways in, depending on how far along you are.
Most people arrive already part-way through the problem. Pick the one that matches where your decision actually sits.
Library screen
Search a broad set of candidate compositions in one run, then narrow to the regions worth a closer look.
Targeted deposition
Already narrowed the system? Skip the library and deposit the known composition straight away, as a uniform film or a test structure.
Off-gradient reproduction
The last step after a screen. A wafer hit comes back as a uniform film, ready to test.
Applications
Where a composition search is the real problem.
- Ohmic contact and diffusion-barrier metallization stacks for SiC and GaN power devices.
- EUV mask absorber alloys, screened for amorphous or nanocrystalline structure and for thermal stability after anneal. Optical constants at 13.5 nm run at a synchrotron.
- Getter films for wafer-level vacuum packaging. Activation temperature is screened by sweeping resistance across every position on one wafer, and sorption capacity per composition runs in your chamber or with a vacuum partner.
- Soft magnetic films for on-package voltage regulators, mapped for resistivity, amorphous against crystallized structure, and film stress, by four-point probe, XRD and cantilever arrays. Permeability and core loss run on your rig.
- Platinum-group metal loading traded against contact resistance and corrosion current on bipolar plates and porous transport layers, mapped by four-point probe and scanning droplet cell (SDC).
- Reduced-iridium catalyst libraries for oxygen evolution in acidic PEM electrolyser conditions.
- The competing chlorine reaction is what a seawater catalyst has to beat, so oxide and alloy libraries are screened for oxygen-evolution selectivity over it in alkaline seawater.
- Tungsten and refractory alloy libraries for plasma-facing components, screened for phase stability and oxidation resistance. Ion irradiation runs at external beam facilities, and there is published precedent for irradiating a whole library and screening damage tolerance across the spread.
- Oxidation and CMAS hot-corrosion resistance in thermal protection coatings, under extreme thermal load.
- Propellant is moving from xenon to krypton and iodine, which retires the existing material compatibility list for electric propulsion. Candidate wall and emitter compositions are screened for phase presence before exposure, and erosion exposure runs in your chamber or with a beam partner.
- Sc content and dopants across the AlN and AlScN family, mapped against orientation, defect density, d33 and film stress on one wafer.
- Higher Sc raises the piezoelectric response and also raises film stress and the odds of abnormal grains, so the usable window is a band rather than a maximum, and a map is the way to find its edges.
- Magnet libraries screened for magnetic moment and coercivity without rare-earth elements, mapped by magneto-optic Kerr effect at every position.
- Device-level resonator performance and full hysteresis loops run on your side. The map narrows which compositions are worth that time.
- Composition and process windows for microwave loss in resonator and qubit films, mapped against structure and film stress on one wafer.
- Nitride and alloy superconductor families where the transition temperature and the loss tangent pull in different directions, so the useful window is narrow and worth locating before a fab run.
- Surface and interface oxides are where much of the loss lives, so XPS and ion-beam analysis run alongside the structural map rather than after it.
- Combinatorial screening has two decades of published work behind it, and no one has yet published one for this film family. Whoever runs it first holds the reference map. Cryogenic microwave measurement stays with you or a partner.
- Electrode coating families screened for charge injection against dissolution, with electrochemistry run automatically at every position by scanning droplet cell.
- Charge injection capacity and impedance are measured per position, so the trade against how fast the coating gives way is visible as a map rather than inferred from a handful of samples.
- Oxide, nitride and noble-metal coating families all sit in the same run, which is what makes the comparison fair.
- Chronic in-vivo testing and biocompatibility work stay with you or your partner. The map narrows what is worth putting into that queue.
What you get back
The map decides what gets tested next.
The map ties composition to what was measured: where a phase boundary sits, where conductivity drops, where a property peaks. Off-gradient reproduction runs when a uniform film is the goal. Final integration and qualification testing stays downstream with you or your partner.
The physical library
One wafer holding a smooth spread of compositions, so neighbors are judged side by side from the same run.
The mapped dataset
Structure, composition and response, tied to each of the 342 spots, with candidate and ruled-out regions marked.
The systems it spans
Metals, nitrides, oxides, fast-ion conductors, and alloy or catalyst systems built from many elements.
Off-gradient reproduction
A chosen composition, made again as a uniform film you can put straight into testing. Formats also include layer stacks, test structures and coated components.
Technical basis
Make it fast, then measure every point fast.
The hard part is measuring enough to trust the map, then rebuilding the winner as a uniform film without losing what made it good.
Library format
One wafer carries the whole composition spread and is read at every position.
Mapped positions
Enough resolution to catch where a property peaks or drops off between the two ends of the spread.
Sputter sources
Seven sources set the composition during the run, so no custom alloy target has to be ordered first.
Elements available
Any ternary or higher system built from them, spread across one wafer.
Characterization methods
The probe follows the target property. Deeper tools come in when interface, surface state, or depth profile controls the result.
Contact
Start a conversation.
Bring a composition system, a functional target, and where it has to end up. A first call sorts out which of the three entry points fits, and most projects then start with a written proposal covering scope, timing and price before any deposition runs. That proposal also settles confidentiality and who owns the resulting data.
Email Parker Schmidt
Parker Schmidt, Commercial Lead
[email protected]