Thermal Evaporation¶
Thermal evaporation is a physical vapor deposition technique where source materials are heated in vacuum until they evaporate and condense onto substrates. It's particularly useful for depositing metals and some semiconductors.
Overview¶
This schema package defines thermal evaporation processes with detailed control of:
- Source material heating (resistive, electron beam)
- Deposition rates and film thickness
- Substrate temperature
- Chamber vacuum conditions
The thermal evaporation process extends NOMAD's Process and Activity base classes, providing:
- Links to input entities (substrates, source materials) and output entities (samples/libraries)
- Evaporation parameters (heating method, power, rate, thickness)
- Vacuum conditions and deposition control
- Automated workflow integration
Typical Usage¶
- Set up deposition: Reference substrates to use and source materials
- Configure evaporation: Set heating method, power, target rate, final thickness
- Control conditions: Chamber pressure, substrate temperature
- Document deposition: Record actual rates, thickness uniformity
- Link output: Reference the samples or libraries created
Key Parameters¶
- Source material: Composition, purity, loading
- Heating method: Resistive heating (boat/crucible), electron beam
- Deposition control: Rate, thickness, shutter timing
- Vacuum: Base pressure, working pressure
- Substrate handling: Temperature, rotation, shutter control
Common Applications¶
- Metal contacts: Electrode deposition for electrical measurements
- Seed layers: Nucleation layers for subsequent growth
- Simple compounds: Materials that evaporate congruently
- Multi-layer structures: Sequential deposition of different materials
Thermal Evaporation vs. Sputtering¶
Use thermal evaporation when:
- You need very gentle deposition (less energetic than sputtering)
- Working with materials that evaporate cleanly
- Depositing thick metal layers quickly
Use sputtering when:
- You need better stoichiometry control (especially for alloys/compounds)
- Creating composition gradients (combinatorial libraries)
- Working with refractory materials
- Depositing oxides or nitrides
Related Schemas¶
- Input entities: Substrates, source materials
- Instrument: DTUInstrument (evaporator)
- Output entities: Samples and Libraries
- Follow-up processes: RTP for annealing
- Characterization: XRD, XPS, Ellipsometry
Schema Documentation¶
DtuThermalEvaporation¶
inherits from: nomad_material_processing.vapor_deposition.pvd.thermal.ThermalEvaporation, nomad.datamodel.data.EntryData
normalization:
The normalizer for the ThermalEvaporation class.
Args: archive (EntryArchive): The archive containing the section that is being normalized. logger (BoundLogger): A structlog logger.