Gas Supplies

Gas supplies track the process gases used in deposition and annealing. Proper gas documentation ensures reproducibility and helps troubleshoot contamination issues.

Overview

This schema package defines:

• DTUGasSupply - A gas cylinder or supply with gas type, purity, cylinder number, and supplier information

Gas supplies extend NOMAD's CompositeSystem entity, providing:

• Unique lab IDs for inventory management
• Gas composition (Ar, O₂, N₂, etc.)
• Purity specifications (99.999%, etc.)
• Cylinder identification numbers
• Supplier and batch tracking

Typical Usage

1. Register gas cylinders: When cylinders arrive, create DTUGasSupply entries with purity and cylinder numbers
2. Reference in processes: Sputtering and RTP processes reference the gas supplies used
3. Track consumption: Monitor cylinder usage and replacement schedules
4. Quality control: Link film properties to specific gas batches for contamination troubleshooting

Why Track Gas Supplies?

Gas quality is critical for many processes:

• Purity matters: Even trace impurities can affect film properties (especially for electronic materials)
• Contamination troubleshooting: If unexpected impurities appear, gas supply records help identify the source
• Reproducibility: Different gas suppliers or batches can produce different results
• Cost management: High-purity gases are expensive; tracking helps optimize usage

Common Gases at DTU Nanolab

• Argon (Ar) - Sputter gas (typically 99.999% purity)
• Oxygen (O₂) - Reactive sputtering, oxidation treatments
• Nitrogen (N₂) - Nitride formation, inert atmosphere
• Forming gas (H₂/N₂) - Reduction and annealing

Related Schemas

• Used in: Sputtering Deposition, RTP
• Creates: Samples and Libraries (via synthesis processes)
• Co-used with: Targets, Instruments

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Schema Documentation

DTUGasSupply

description: Class autogenerated from yaml schema.

inherits from: nomad.datamodel.metainfo.basesections.v1.CompositeSystem, nomad.datamodel.data.EntryData

properties:

name	type
in_use	bool	Indicates whether the gas supply is currently in use. default=False
molecular_formula	str	The molecular formula of the gas, in lower case (Ex: h2s for 10% H2S in Ar, ar for Ar). This ensure functioningreferencing.
molecular_mass	float64	unit=gram
cas_number	str
supplier_id	str
purity	float64
impurities	str
date_of_production	nomad.metainfo.data_type.Datetime
date_of_installation	nomad.metainfo.data_type.Datetime
total_volume_consumption	float64	unit=meter ** 3
time_used_gas	float64	unit=second
gas_name	str
iupac_name	str
inchi	str
inchi_key	str
smiles	str
canonical_smiles	str
test_var	['Gas', 'Gas2', 'Gas3']	default=Gas

normalization:

The normalizer for the DTUGasSupply class.

Args: archive (EntryArchive): The archive containing the section that is being normalized. logger (BoundLogger): A structlog logger.