Method of using square-recess embedded substrate support to inhibit growth of polycrystalline diamond

Abstract

The invention discloses a method of using a square-recess embedded substrate support to inhibit the growth of polycrystalline diamond; the method comprises: manufacturing a substrate support, and making two concentric square recesses in the center of the surface of the substrate support; grinding and polishing the surface of the substrate support and the insides of the recesses; ultrasonically washing with absolute ethyl alcohol, and washing with plasma; ultrasonically washing a monocrystalline diamond substrate with acetate, placing in a substrate support recess, and fitting a growth device; washing a substrate with plasma in the growth device; adding methane to growth monocrystalline diamond. As graphite deposits between the substrate and the substrate support, the lateral sides of the substrate come in contact with the substrate support, substrate edge cooling effect is improved, and temperature uniformity of the whole monocrystalline diamond substrate is optimized, with polycrystalline growth at the edge of the substrate greatly avoided. Experiments discover that it is possible to effectively inhibit the edge polycrystal during the growth of monocrystalline diamond by using the square-recess embedded substrate support, and monocrystalline diamond samples with non-reduced size can be acquired.

Description

technical field [0001] The invention relates to the preparation of single crystal diamond material, in particular to a method for suppressing the growth of polycrystalline diamond by using a square groove inlaid substrate holder. Background technique [0002] Single crystal diamond has excellent semiconductor properties, such as the highest thermal conductivity (22 W / cm×K), extremely high breakdown voltage (> 10 MV / cm), large band gap (5.5 eV), and ultrahigh Therefore, it has great application requirements in many fields, such as detectors under harsh conditions, micro / nano electromechanical systems, quantum computing, etc., especially in high temperature and high power devices. Application advantages. For this reason, the size and quality of single crystal diamonds are extremely important. At present, microwave plasma chemical vapor deposition (MPCVD) is the best method to prepare high-quality large-size single crystal diamond. This method usually uses an open substra...

AI Technical Summary

Problems solved by technology

This method usually uses an open substrate holder structure (such as figure 1 , figure 2 As shown), this structure has the following problems in MPCVD growth: (1) the surface temperature of the single crystal diamond substrate is not uniform (the edge temperature is higher than the center); (2) the entire single crystal substrate is plasma-wrapped, and the processing level Poor edges tend to induce polycrystalline growth

Due to the existence of these two problems, a large number of polycrystals will inevitably be produced at the edge of the substrate during the growth of single crystal diamond, and there are still problems such as edge polycrystal growth and expansion, which seriously affect the surface quality and crystal size of single crystal diamond.

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