An improved matrix separation method for characterization of ultrapure germanium (8N)

Area of Science:

• Analytical Chemistry
• Materials Science
• Inorganic Chemistry

Background:

• Ultrapure germanium is crucial for advanced semiconductor and detector applications.
• Accurate characterization of trace impurities in high-purity germanium is essential for performance.
• Existing methods may lack the sensitivity or specificity for 8N purity germanium.

Purpose of the Study:

• To develop and optimize a matrix separation method for characterizing 8N purity germanium.
• To achieve quantitative removal of the germanium matrix from trace impurities.
• To establish a sensitive and accurate analytical procedure for impurity determination.

Main Methods:

• Optimization of reaction temperature for in-situ chlorine gas reaction with germanium.
• Quantitative recovery studies for over 60 elements at the optimized temperature (230±5°C).
• Impurity determination using Inductively Coupled Plasma Quadrupole Mass Spectrometry (ICP-QMS) and High-Resolution Continuum Source Graphite Furnace Atomic Absorption Spectrometry (HR-CS-GFAAS).

Main Results:

• Quantitative removal of the germanium matrix achieved at 230±5°C.
• High recoveries (>90%) for most analytes, with exceptions noted for As, Se, Sn, Hg, Tl.
• Method demonstrated suitability for up to 10g Ge samples, yielding low parts per billion/trillion process blanks.
• Achieved low limits of detection (LOD) between 1.8-0.003 ng/g for impurities.

Conclusions:

• The developed matrix separation method is effective for characterizing 8N purity germanium.
• The method provides high accuracy and precision for trace impurity analysis.
• Successfully applied to the characterization of ultrapure germanium materials.