GB/T 42271-2022Test method for resistivity of semi-insulating monocrystalline silicon carbide by contactless measurement (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 for Standardization Documents" drafting.

1 Scope

This document describes a method for the non-contact measurement of resistivity of semi-insulating silicon carbide single crystals.

This document is applicable to the measurement of semi-insulating silicon carbide single wafers with resistivity ranging from 1 x 10^5ohm·cm to 1 x 10^12ohm·cm.

2 Normative references

The contents of the following documents constitute the essential provisions of this document through normative references in the text. Among them, dated references For documents, 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 14264 Terminology of semiconductor materials

GB/T 30656 Silicon carbide single crystal polished wafer

3 Terms and Definitions

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

4 Principles

The non-contact resistivity test uses the principle of capacitive charge and discharge. First charge the sample instantaneously, and then use the instrument to monitor the discharge in real time In order to obtain the relaxation curve of the change, the relaxation time (tau) is obtained by mathematical analysis of the curve, and finally through The relaxation time (tau) was used to calculate the resistivity of semi-insulating SiC single crystals.

5 Test conditions

5.1 The test machine used in the test process should have no vibration, no electromagnetic interference and be well grounded.

6 Interfering factors

6.1 Different light intensities will affect the test results of resistivity, and the hood of the equipment should be closed during the test.

6.2 Static electricity and vibration test environment will affect the test results of resistivity, and strict shielding measures should be taken during the test.

6.3 Particle contamination on the surface of the sample, the adsorption stage and the test probe will affect the resistivity of the semi-insulating silicon carbide single wafer.

Confirm that the surface of the sample, the adsorption stage and the test probe are free of large particles visible to the naked eye.

6.4 Changes in sample thickness will affect the test results of resistivity, and the sample thickness should be uniform before testing.