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PVD technique
Thermal evaporation
Thermal evaporation heats source material under vacuum until it evaporates and condenses onto the substrate. It can be useful for selected metals, organic materials and low-temperature or plasma-sensitive research workflows where material behaviour is compatible.
Plain language guide
What this means in practice
Thermal evaporation heats a source material in vacuum until it evaporates and travels to the substrate. It is often useful for metals, organics and other materials where a plasma process would be too aggressive or unnecessary.
What happens in the system
- A compatible source material is loaded into a boat, crucible, basket or low-temperature source.
- The chamber is pumped down and the source is heated until material begins to evaporate.
- The vapour travels mostly in straight lines and condenses on the substrate, often through a mask or onto a rotating stage.
What changes the result
- The source hardware must be compatible with the material, otherwise alloying, spitting or contamination can occur.
- Evaporation is strongly line-of-sight, so fixture design and source-substrate geometry matter.
- Organic and low-melting materials need careful rate and temperature control to avoid degradation.
Questions to answer first
- Does the material evaporate cleanly before it decomposes?
- Do you need shadow-mask metallisation, organic films, contact layers or low-temperature deposition?
- Will source changing, masking or multiple materials be part of the normal workflow?
Further reading
Useful external explainers
These neutral references are included to help newer readers understand the underlying process family. Moorfield system suitability still depends on a configuration discussion.
When it helps
Where this technique fits in research workflows
Resistance-heated evaporation for compatible metals, organics and sensitive materials under vacuum. Moorfield can help connect the process requirement to a practical benchtop or modular configuration without treating the guide as a final specification.
Plasma-sensitive materials
Consider thermal evaporation when sputtering plasma would be unsuitable for the material or device stack.
Metallisation and contacts
Thermal evaporation can support selected electrode and contact metallisation workflows.
Small-batch experimentation
Benchtop evaporation helps screen source materials and process windows before committing to larger infrastructure.
Configuration thinking
Map the process need to a platform discussion
The table below is guidance for early selection conversations. It deliberately avoids over-specifying performance before Moorfield has reviewed the material set and lab environment.
| Research need | Relevant process consideration | Potential Moorfield fit |
|---|---|---|
| Metal electrodes and contact layers | Thermal evaporation from compatible sources | nanoPVD-T15A or MiniLab evaporation |
| Organic semiconductor films | Low-temperature evaporation where volatility allows | nanoPVD-T15A discussion |
| Combined deposition work | Thermal evaporation alongside sputtering | nanoPVD-ST15A or MiniLab |
| Protected-transfer requirements | Evaporation in glovebox-compatible modular systems by configuration | MiniLab 090 discussion |
Relevant platforms
Systems to consider
Start with the process requirement, then compare platform size, source options, atmosphere control, substrate handling and future expansion needs.
nanoPVD benchtop systems
Compact deposition systems for local sputtering, evaporation and combined thin-film process development.
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MiniLab modular PVD
Configurable modular platforms for more complex source, chamber, transfer and sample-handling requirements.
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Material selector
Look up chart-based deposition guidance by material before starting a configuration discussion.
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Related technique guides
Move between technique pages to compare process families before using the selector or contacting Moorfield.
Next step
Need help choosing a process?
Tell Moorfield about your material set, substrate size, source preference and target film stack. We can help identify a practical platform and configuration.
Thermal evaporation
Thermal evaporation is a straightforward means of thin film deposition with materials being heated to evaporation temperatures via a resistively heated support.
Thermal evaporation is a widely used technique for depositing thin films and coatings. This process involves heating a material to its evaporation point in a high vacuum chamber, allowing the vapourised atoms to travel and condense on a cooler substrate, forming a thin film.
How Thermal Evaporation Works
The material to be deposited (source material) is heated until it vapourises. This is typically achieved using resistive heating or electron beam heating.
The vapourised atoms travel through the vacuum chamber and condense onto the substrate, forming a thin, uniform film. In thermal evaporation it is important to use a high vacuum to reduce contamination and ensure a mean free path long enough for atoms to travel directly to the substrate. This typically means that evaporation chambers are taller than an equivalent magnetron sputtering system.
Depending on the material, resistive heating (using a heated filament or boat), electron beam heating, or induction heating is used to vapourise the source material.
Common thermally evaporated materials include metals (e.g., gold, aluminium), alloys, and compounds. Substrates must be clean and free from contaminants to ensure good adhesion and uniformity. Some processes require heating the substrate to improve film quality and adhesion.
Operation Considerations
- Temperature: Must be carefully controlled to ensure proper evaporation without decomposition of the source material.
- Deposition Rate: Controlled by adjusting the heating power, affecting film thickness and uniformity.
- Vacuum Level: High vacuum levels are essential to reduce contamination and ensure a direct path for vapour atoms.
