GB/T 40561-2021Photovoltaic silicon material—Determination of oxygen—Pulse heating inert gas fusion infrared absorption method (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

1 Scope

This document describes the method of measuring the oxygen content in photovoltaic silicon materials by pulse heating inert gas melting infrared absorption method.

This document is applicable to the determination of oxygen content in photovoltaic silicon materials such as silicon powder, industrial silicon, and granular polycrystalline silicon, which are raw materials for the production of polysilicon.

The circumference is the mass fraction of oxygen 0.0010%~0.40%. Other types of crystalline silicon materials used in the production of photovoltaic modules are used as reference.

2 Normative references

The content of the following documents constitutes an indispensable clause of this document through normative references in the text. Among them, dated quotations Only the version corresponding to the date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 6379.2 Accuracy of measurement methods and results (accuracy and precision) Part 2: Determine the repeatability of standard measurement methods Basic methods of sex and reproducibility

GB/T 8170 Numerical rounding rules and the expression and determination of limit values

GB/T 14264 Terminology of Semiconductor Materials

3 Terms and definitions

The terms and definitions defined in GB/T 14264 are applicable to this document.

4 Principle

The sample is placed in a degassed graphite sleeve crucible and heated and melted under an inert atmosphere. Oxygen formed by the oxygen in the sample and the carbon in the crucible Carbon and a small amount of carbon dioxide are passed through high-temperature rare earth copper oxide along with helium (or argon) to convert carbon monoxide into carbon dioxide and introduce infrared The detector performs the measurement. According to the change of infrared absorption intensity signal, the oxygen content is calculated.

5 Disturbing factors

5.1 The main factors that have a greater impact on the test results are the uniformity of the sample, the cleanliness of the sample surface, the purity of the inert gas, the graphite crucible and the auxiliary The purity of the reagent material (high-purity nickel capsule), the accuracy and uncertainty of the calibration sample value, the accuracy of the electronic balance, and the optimization of the operating parameters of the instrument Chemical selection, etc.

5.2 The cleanliness of the sample surface affects the test results. If the sample may be contaminated during the sampling and sample preparation process, the sample should be analyzed before analysis. Use a suitable solvent (for example, premium grade or spectrally pure absolute ethanol or isopropanol) to clean the surface and dry it.

5.3 Inert gas (helium or argon) is used as the carrier gas in the test instrument, and its impurities may adsorb the oxygen released by the sample. Affect the accuracy of the test results, high-purity inert gas should be used to improve the accuracy of the test results.

5.4 The oxygen content or impurity content of the graphite crucible and auxiliary materials will affect the accuracy of the analysis data, and high-purity graphite/spectral pure stone should be used Crucible and high-purity auxiliary materials made of ink processing.