English
Researchers from Rice University have proposed an efficient method that combines ion implantation, epitaxial growth, and electrochemical exfoliation for the preparation of high-quality diamond films. Firstly, 3 MeV carbon ions (C2+) were implanted into a commercial chemical vapor deposition (CVD) diamond substrate to form an amorphous carbon layer with a depth of approximately 1.6 μ m; Subsequently, epitaxial growth was carried out using a microwave plasma chemical vapor deposition (MPCVD) system with methane and hydrogen as gas sources at a temperature of approximately 800 ° C. During the growth process, high-temperature annealing was not required, and the amorphous carbon layer was directly transformed into a graphite layer. The structural evolution was verified by high-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS); Finally, electrochemical etching is used to selectively remove the graphite layer, achieving efficient exfoliation of the epitaxial layer while retaining the low roughness (0.3 nm) of the substrate, supporting multiple cycles of use. This method significantly improves the purity of diamond films (with nitrogen vacancy center density close to electronic standards) through interface dynamic control and in-situ graphitization mechanism, providing a sustainable preparation solution for quantum technology and high-performance electronic devices.
