Overview
ISO 8181:2023, titled Atomic Layer Deposition - Vocabulary, is an international standard developed by ISO’s Technical Committee ISO/TC 107. This standard precisely defines general terms and film growth processes related to Atomic Layer Deposition (ALD). ALD is a cutting-edge thin film deposition technique based on sequential and self-limiting chemical reactions of gas phase precursors on substrates, allowing for atomic scale thickness control.
The document covers various ALD classifications such as conventional time separated ALD, spatial ALD, and powder ALD for micro-nano particles. It also includes energy-enhanced ALD methods like plasma-enhanced, photo-assisted, and catalytic ALD. Importantly, ISO 8181:2023 focuses on the ALD processes themselves, not on the materials deposited or specific nanostructures.
This vocabulary standard is essential for ensuring consistent terminology in scientific research, industrial production, education, and technology communications related to ALD across global settings.
Key Topics
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ALD Process Terms
Fundamental definitions such as precursor, self-limiting reaction, half chemical reaction, and growth rate help clearly describe how ALD cycles produce uniform thin films.
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Film Growth Stages
Key terms defining ALD film formation include nucleation, nucleation site, island stage, network stage, and continuous stage, detailing how film morphology evolves during deposition.
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ALD Classifications
ALD is classified by process separation into:
- Time separated ALD - where sequential surface reactions are separated in time.
- Spatial ALD - where the substrate alternately encounters different precursor zones spatially.
Substrate types classify ALD as planar or powder ALD. Reaction activation methods divide ALD further into thermal, plasma-enhanced, photo-assisted, and catalytic ALD.
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Specialized Terms
Terms such as inert gas, carrier gas, precursor exposure, inert gas purge, and vacuum-related parameters aid in describing ALD process environments.
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Selectivity and Energy
Vocabulary includes selective atomic layer deposition, selectivity, facet selectivity, and various energy terms like precursor bonding energy and activation energy crucial for understanding reaction mechanisms.
Applications
ISO 8181:2023 supports professionals involved in:
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Industrial Production
Helping manufacturers apply standardized ALD terminology for coating uniform thin films on electronics, photovoltaics, and flexible substrates.
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Scientific Research
Guiding researchers in communicating precise ALD process details and advances in micro-nano particle coatings and energy-enhanced ALD.
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Education & Publishing
Offering clear ALD vocabularies for curriculum development, technical documentation, and academic journals worldwide.
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Technology Communication
Facilitating consistent, global exchanges in conferences, patents, and cross-industry collaborations concerning ALD advancements.
Related Standards
- ISO/TS 80004-8:2020 – Defines vocabularies on nanomanufacturing processes related to ALD.
- ISO 20523:2017 – Covers carbon-based film classification, complementing ALD thin film standards.
- ISO 18115-1:2023 – Provides general surface chemical analysis terminology used in ALD film characterization.
Summary
ISO 8181:2023 is a foundational vocabulary standard for Atomic Layer Deposition, covering critical process definitions, classification schemes, and operational terminology. By adopting this standard, industries and researchers ensure uniform understanding and communication of ALD techniques-enabling precise control of ultra-thin films and expanding ALD applications from electronics to biomedicine. This standard is indispensable for advancing innovation, quality control, and international collaboration in the growing field of atomic layer deposition.