ISO 14606:2022

Overview

ISO 14606:2022 - "Surface chemical analysis - Sputter depth profiling - Optimization using layered systems as reference materials" provides guidance and requirements to optimize sputter depth profiling for surface chemical analysis. It specifies how to use single-layered and multilayered reference materials to achieve optimum depth resolution as a function of instrument settings in Auger electron spectroscopy (AES), X‑ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS). The standard is explicit that special multilayer systems such as delta-doped layers are out of scope.

Key topics and requirements

• Optimization approach: Use of layered reference systems (single and multilayer) to evaluate and set instrument parameters for best depth resolution.
• Instrument families covered: AES, XPS, SIMS - including probing and sputtering parameter considerations for each technique.
• Critical parameters:
  • Probing: electron/photon/primary ion energy, beam/current or source power, analysis area, emission angle.
  • Sputtering: ion species, ion energy (typical range 0.1–25 keV in the standard), ion beam current (examples 1–10 nA), incidence angle, sputtered area and rastering.
• Measurement and metrics:
  • Determination of average sputtering rate and the depth resolution (Δz) at an ideally sharp interface.
  • Guidance on measuring depth resolution using layered references, and caveats for SIMS when matrix effects differ.
• Procedures and alignment:
  • Practical procedures to align a sputtered crater with a smaller analysis area (including manufacturer-provided alignment tools).
  • Stepwise optimization of parameter settings to balance analysis sensitivity versus depth resolution.
• Supporting material: Informative annexes on factors influencing depth resolution, typical reference single- and multilayer systems, and uses of multilayered systems.

Applications and users

ISO 14606:2022 is practical for:

• Surface analysts and lab technicians performing sputter depth profiling in AES, XPS and SIMS.
• Instrument manufacturers validating and demonstrating performance.
• Materials scientists and semiconductor engineers characterizing multilayer devices (e.g., optical/heterostructure devices) and coatings.
• Quality and metrology labs assessing depth profiling reproducibility and instrument settings.

Practical uses include optimizing ion beam conditions to reduce sputter-induced roughening, evaluating sample drift and crater geometry effects, and choosing suitable reference materials for method development.

Related standards

• Normative reference: ISO 18115-1 (Surface chemical analysis - Vocabulary).
• Developed by ISO/TC 201 (Surface chemical analysis) - useful alongside other ISO guidance on surface analysis and metrology.

Keywords: ISO 14606:2022, sputter depth profiling, surface chemical analysis, depth resolution, reference materials, AES, XPS, SIMS, ion sputtering.