GB/T 41153-2021Determination of boron, aluminum and nitrogen impurity content in silicon carbide single crystal—Secondary ion mass spectrometry (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" drafted.

1 Scope

This document specifies the secondary ion mass spectrometry test method for the impurity content of boron, aluminum and nitrogen in silicon carbide single crystal.

This document is applicable to the quantitative analysis of boron, aluminum and nitrogen impurity content in silicon carbide single crystal.

The aluminum content is not less than 5 x 10^13 cm^-3, the nitrogen content is not less than 5 x 10^15 cm^-3, and the element concentration (atom number percentage) is not more than 1%.

Note 1. The content of the element to be measured in the silicon carbide single crystal is measured in the number of atoms per cubic centimeter.

Note 2. The determination of vanadium impurity content in silicon carbide single crystal can refer to this document, and the determination range is that the vanadium content is not less than 1 x 10^13 cm^-3.

2 Normative references

The contents of the following documents constitute essential provisions of this document through normative references in the text. Among them, dated citations documents, only the version corresponding to that date applies to this document; for undated references, the latest edition (including all amendments) applies to this document.

GB/T 14264 Terms of Semiconductor Materials

GB/T 22461 Surface Chemical Analysis Vocabulary

GB/T 32267 Analytical Instrument Performance Determination Terms

3 Terms and Definitions

Terms and definitions defined in GB/T 14264, GB/T 22461 and GB/T 32267 apply to this document.

4 Principles

Under the condition of high vacuum (vacuum degree better than 5 x 10^-7 Pa), the primary ions generated by oxygen or cesium ion source are accelerated, purified and focused.

After bombarding the surface of the silicon carbide single crystal sample, a variety of particles were sputtered. The ions (ie secondary ions) are extracted, and the different The ions of the mass-to-charge ratio were separated, and the ratio of the ion count rate of the element to be tested to the main element silicon in the sample was recorded and calculated. Using relative sensitivity factors Quantitatively analyze and calculate the content of the analyte element in the silicon carbide single crystal.

5 Interfering factors

5.1 The secondary ion mass spectrometer has a memory effect. If a sample with a high content of the element to be tested has been tested, a high content will remain in the sample chamber of the instrument.

The element to be tested affects the test result of the content of the element to be tested.

5.2 Different models of instruments or different states of the same instrument (such as electron multiplier efficiency, aperture size, primary beam size, focus state, etc.), which will affect the detection limit of this method.

5.3 The vacuum level of the sample chamber will affect the accuracy of the nitrogen content test results.

5.4 The analyte ions adsorbed on the sample surface may affect the test results of its content.

5.5 The sample analysis surface within the window of the sample holder should be flat to ensure that when each sample moves to the analysis position, its surface and ion receiving […]