Detection method for two-dimensional layered material heterojunction stacking sequence, and spectral measurement system

Abstract

Embodiments of the invention provide a detection method for a two-dimensional layered material heterojunction stacking sequence, and a spectral measurement system. The method comprises the steps of acquiring secondary harmonic spectrums corresponding to a single-layer-shaped material region and a heterojunction region in a to-be-detected heterojunction at different rotation angles; extracting secondary harmonic signal peaks corresponding to the single-layer-shaped material region and the heterojunction region in the secondary harmonic spectrums at different rotation angles; acquiring a first polar coordinate distribution diagram and a second polar coordinate distribution diagram according to the secondary harmonic signal peaks; comparing the secondary harmonic signal intensities in the first polar coordinate distribution diagram and the second polar coordinate distribution diagram to obtain a stacking sequence detection result of the heterojunction. According to the method, a characteristic that secondary harmonic signals are zero when layered materials are stacked to form a central symmetric structure is used, and an optical means is adopted as a probe, so that the requirements for a heterojunction sample are reduced, and the sample does not need to be transferred to a target carrier net; the detection method is simple and convenient; and rapid nondestructive testing is realized.

Description

technical field [0001] Embodiments of the present invention relate to the field of material technology, and more specifically, to a detection method and a spectral measurement system for a heterojunction stacking sequence of a two-dimensional layered material. Background technique [0002] The preparation methods of two-dimensional layered materials include chemical vapor deposition and mechanical exfoliation. Usually, the sample size of mechanical exfoliation is about several microns, while the chemical vapor deposition method can synthesize samples with a size of hundreds of microns. Two single-layer layered materials are stacked together by the transfer method. However, since the crystal axis orientation of the material cannot be distinguished by the naked eye, the stacking sequence of the heterojunction is relatively random. Therefore, in order to determine the stacking sequence of the heterojunction, a high-definition transmission electron microscope is usually used in ...

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Problems solved by technology

However, this method has high requirements for the sample, and the sample needs to be transferred to the mesh net, and the process is relatively complicated.

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