Overview
ISO/TR 19319:2013 - "Surface chemical analysis - Fundamental approaches to determination of lateral resolution and sharpness in beam-based methods" - is an informative Technical Report from ISO/TC 201 that describes fundamental concepts, definitions and experimental approaches to quantify lateral resolution and image sharpness for beam-based surface-analytical imaging (e.g., SIMS, AES, XPS). The report (second edition, 2013) explains the relationship between image-formation functions and practical measurement methods and provides guidance specific to Auger electron spectroscopy (AES) and X‑ray photoelectron spectroscopy (XPS).
Key topics
- Definitions and core functions relevant to lateral resolution:
- Point Spread Function (PSF)
- Line Spread Function (LSF)
- Edge Spread Function (ESF)
- Modulation Transfer Function (MTF)
- Contrast Transfer Function (CTF)
- Experimental methods for determining lateral resolution and sharpness:
- Imaging of a narrow stripe
- Imaging of a sharp edge (knife-edge method)
- Imaging of square‑wave gratings (including effective cut-off frequency and generalized CTF)
- Quantitative definitions and metrics:
- Effective lateral resolution (criterion: dip between two maxima ≥ 4 × reduced noise σNR)
- Analysis area and sample area viewed by the analyser (definitions and measurement guidance for AES/XPS)
- Physical factors affecting lateral resolution and analysis area in AES and XPS (instrument and sample-related influences)
Practical applications
- Standardizes how to evaluate and compare image resolution and sharpness of surface-analytical instruments.
- Supports instrument performance testing, acceptance checks and inter-laboratory comparison for imaging SIMS/AES/XPS systems.
- Guides the design and use of test specimens (narrow stripes, edges, square‑wave gratings) to assess spatial resolution and contrast transfer.
- Helps interpret imaging results in materials science, semiconductor analysis, corrosion studies and thin-film characterization where spatially resolved surface chemistry is critical.
Who should use this standard
- Surface chemical analysis practitioners and laboratory managers
- Instrument manufacturers and calibration technicians
- Metrology and standards laboratories performing AES/XPS performance verification
- Researchers developing imaging methods or test specimens for lateral resolution characterization
Related standards
- ISO 18516 (lateral resolution using knife‑edge methods)
- ISO 22493 (image resolution terminology in microscopy)
- ISO 18115 (surface analysis vocabulary)
Keywords: lateral resolution, surface chemical analysis, beam-based methods, AES, XPS, PSF, LSF, ESF, MTF, CTF, square-wave gratings, image sharpness, analysis area.