Overview
ISO 17331:2004/Amd 1:2010 is an important international standard focused on surface chemical analysis of silicon-wafer working reference materials. This amendment updates and refines the chemical methods used for collecting elements, specifically iron and nickel impurities, from the surface of silicon wafers. The collected elements are then measured through total-reflection X-ray fluorescence (TXRF) spectroscopy. ISO, the global standardization organization, prepared this amendment to enhance accuracy, clarify terminology, and address patent considerations relating to the chemical collection methods.
Key Topics
-
Chemical Collection Methods: The standard specifies two main approaches for collecting surface contaminants from silicon wafers:
- Vapour-phase decomposition method
- Direct acid droplet decomposition method
-
Elemental Analysis by TXRF Spectroscopy: The collected impurities, mainly nickel and iron, are quantified using total-reflection X-ray fluorescence spectroscopy, a highly sensitive and non-destructive analytical technique ideal for surface contamination assessment.
-
Patent and Licensing Information: The amendment acknowledges identified patents related to the collection methods and provides information on patent holders-Toshiba Corporation and Covalent Materials Corporation-with assurances of reasonable licensing terms.
-
Chemical Reagents: Specifications for reagents such as semiconductor-grade nitric acid are included to ensure consistency and accuracy in chemical processing.
-
Standardization Improvements: The amendment refines procedural details including solution volumes, drying procedures, and apparatus usage (e.g., vertical laminar-flow cabinets) to improve method reliability and repeatability.
Applications
This ISO standard amendment is crucial for industries and laboratories involved in:
-
Semiconductor Manufacturing: Ensuring silicon wafer surface purity by accurately detecting and measuring trace metallic contaminants that could impair semiconductor device performance.
-
Surface Analysis Laboratories: Employing standardized chemical collection methods combined with TXRF spectroscopy to verify surface cleanliness and material quality.
-
Quality Control and Reference Material Calibration: Providing validated protocols to assess working reference materials used as benchmarks for contamination levels.
-
Research and Development: Supporting the development of new materials and contamination control processes by offering precise surface chemical analysis techniques.
Related Standards
Professionals utilizing ISO 17331:2004/Amd 1:2010 may also consider these related standards to complement surface chemical analysis practices:
- ISO/IEC Directives, Part 2 - Guidelines for drafting ISO standards.
- Standards on TXRF Spectroscopy - For instrument calibration and method validation.
- Standards on Wafer Surface Contamination Analysis - Covering advanced surface chemical characterization techniques.
- Patent Licensing Policies - ISO’s Common Patent Policy for implementation guidance in technology standards.
By adhering to ISO 17331 and its amendments, organizations can ensure compliance with globally recognized methods for collecting and analyzing elemental contamination on silicon wafer surfaces, thereby supporting product reliability and technological advancement in semiconductor fields.
Open preview (PDF)Surface chemical analysis — Chemical methods for the collection of elements from the surface of silicon-wafer working reference materials and their determination by total-reflection X-ray fluorescence (TXRF) spectroscopy — Amendment 1
