Overview
ISO 17560:2014 specifies a standardized secondary‑ion mass spectrometry (SIMS) method for depth profiling boron in silicon. It covers procedures using magnetic‑sector or quadrupole mass spectrometers and prescribes depth‑scale calibration by stylus profilometry or optical interferometry. The method applies to single‑crystal, polycrystalline, or amorphous silicon specimens with boron concentrations from 1 × 10^16 to 1 × 10^20 atoms/cm^3 and to crater depths of 50 nm or deeper.
Key topics and requirements
- Instrumentation: Use of magnetic‑sector or quadrupole SIMS; oxygen‑ion (O2+) primary beam with positive secondary‑ion polarity or cesium (Cs+) beam with negative polarity.
- Detected species: Monitor boron isotopes and appropriate silicon matrix ions (including B, B‑Si cluster ions depending on beam type).
- Depth calibration: Measure sputter crater depth by stylus profilometry or optical interferometry (optical interferometry generally suited to ~0.5 μm–5 μm crater depths). Certified reference materials traceable to standards are required for profilometer calibration.
- Concentration calibration: Follow ISO 14237 for determination of relative‑sensitivity factors (RSF) and mass discrimination corrections to convert SIMS signals into boron atomic concentration.
- Measurement practice: Alternate and cycle boron and silicon ion measurements; select primary‑ion beam current and scan area to capture profile details while avoiding detector nonlinearity at high count rates. Use consistent instrument transmission settings for reference and test specimens.
- Specimen prep and quality: Cut to appropriate size, degrease/wash as needed. Surface roughness affects depth accuracy-mirror‑polished wafers are preferred for precise depth‑scale determination.
- Background and interference: Be aware of residual gases and hydrogen-related species (e.g., B‑Si‑H) that can create background signals; maintain appropriate vacuum and instrument conditions.
Applications and users
ISO 17560 is intended for:
- Semiconductor process engineers and failure‑analysis labs performing boron dopant profiling in silicon devices.
- Materials and surface analysis laboratories using SIMS for quantitative depth profiles.
- Quality assurance teams in microelectronics manufacturing requiring traceable, reproducible boron concentration and depth measurements.
Practical uses include dopant profiling for device fabrication, diffusion studies, ion‑implantation verification, and research into dopant distribution in silicon wafers and thin films.
Related standards
- ISO 14237:2010 - Surface chemical analysis - SIMS - Determination of boron atomic concentration in silicon (used for RSF and concentration calibration).
Keywords: ISO 17560, depth profiling boron in silicon, SIMS, secondary‑ion mass spectrometry, stylus profilometry, optical interferometry, magnetic‑sector, quadrupole, RSF, ISO 14237.
Open preview (PDF)Surface chemical analysis — Secondary-ion mass spectrometry — Method for depth profiling of boron in silicon