A Method for Epitaxial Growth of High Quality and Large Size Single Crystal Diamond

Abstract

A method for epitaxial growth of high-quality and large-size single crystal diamond belongs to the field of semiconductor material preparation. The method is to reduce the surface roughness to less than 0.2nm by precision polishing the large-size single crystal diamond sheet grown by mosaic splicing. Then use electron beam evaporation to deposit metal nickel with a thickness of 100nm-200nm on the surface at a rate of 0.01nm / s-0.1nm / s while heating the substrate at 100-500°C, and then deposit nickel at a rate of 0.01nm / s-0.5nm / s. The speed of s deposits metallic iridium. After the iridium thickness reaches 15nm-40nm, increase the heating temperature of the substrate to 700-1000°C and accelerate the deposition rate to 0.5nm / s-1nm / s, and finally deposit a thin layer of iridium with a total thickness of 150nm-300nm. Then, the plasma chemical vapor deposition technology is used to pre-deposit a 4-10nm amorphous carbon layer after hydrogen plasma cleaning the iridium surface to promote the enrichment of carbon atoms on the subsurface of the iridium thin layer. Finally, after etching the substrate with pure hydrogen plasma for 6-15s, the negative bias voltage and methane flux were adjusted to realize the biased in-situ nucleation of large-sized single crystal diamond on the iridium surface and the subsequent unbiased epitaxial growth.

Description

Technical field: [0001] The invention relates to the field of preparation of matrix materials for semiconductors. In particular, the preparation of high-quality large-size single crystal diamond provides a material preparation basis for the further realization of diamond-based semiconductor devices. That is, by depositing a metal nickel transition layer and a thin iridium layer on a high-gloss large-scale mosaic splicing single-crystal diamond self-supporting substrate. And the chemical vapor deposition method is used to pre-deposit an amorphous carbon thin layer on the surface of metal iridium, followed by pure hydrogen etching, and finally adjust the methane flux to realize the single-oriented crystallization of the iridium thin layer and the in-situ nucleation and growth of diamond, which is highly efficient. High-quality and large-size single crystal diamond can be obtained by heteroepitaxial method. [0002] technical background [0003] Diamond has extremely excellent...

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Problems solved by technology

However, the adhesion problem of the diamond layer caused by the large difference in thermal expansion coefficient is an important difficulty

However, due to the large lattice mismatch problem between the transition layer and iridium, the deposition growth and dislocation density control of the metal iridium layer have also become important problems in single crystal diamond epitaxy (Comprehensive Hard Materials, 3, 269-304, ( 2014))

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