Method for testing GaN single-crystal fault kind and density

Abstract

The invention discloses a detection method of the GaN single-crystal defective kinds and the density which is to improve the traditional wet corrosion detection technology to match the GaN material. The invention detects the surface of the sample by amplifying the SEM magnification times and reducing the AFM detection section step by step. Also it uses the AFM deep section topography and skips over the corrosion condition. It ensures the solid shape of the corrosion pit by compounding the SEM and the AFM to determine the corresponding relation of the corrosion pit and the flaw type by compounding the physical model of the corrosion mechanism. It computes the density and the distributing of all kinds of the flaws by reading the SEM picture. The invention is simple and proper for detecting the industry production.

Description

technical field [0001] The invention relates to the technical field of semiconductor material quality detection, in particular to a detection method for the type and density of GaN single crystal defects, which can be used to determine the type of line defects within 100nm below the surface of a c-plane GaN single crystal thin film grown by heterogeneous epitaxy vs density, suitable for etch pit density EPD at 10 7 ~10 8 / cm 2 Various doped or undoped GaN single crystal materials with good conductivity. Background technique [0002] At present, the most convenient and effective method for the quality inspection of semiconductor single wafers is wet etching, which has been widely used in Si and GaAs materials. There are three keys to this technology: 1. Find the corresponding relationship between corrosion pits and defects to determine the type of defects; 2. Find the optimal corrosion conditions to reveal as many defects as possible; 3. Perform microscopic observation acc...

AI Technical Summary

Problems solved by technology

They are all effective technical means to characterize the microscopic morphology of the material surface, but each has its own advantages and disadvantages in correctly counting the corrosion pit density: AFM does not require the conductivity of the sample, and can perform depth profile analysis, but the selection and scanning time are longer, It is not conducive to averaging a large number of observations, and is limited by the needle tip effect, and the shape of some corrosion pit surfaces is distorted

SEM is easy to operate and has high precision, but it has requirements for conductivity and cannot determine the depth of corrosion pits

In addition, the existing reports failed to make full use of the advantages of these two techniques to accurately and easily observe the corrosion pit density by optimizing the corrosion conditions.

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