Growth mechanisms and material properties of boron-doped single crystal diamond synthesized by HFCVD

The synthesis of boron(B)-doped single crystal diamond (SCD) using the hot-filament chemical vapor deposition (HFCVD) method has garnered significant attention due to its promising applications. This study investigates the growth mechanism and performance characterization of HFCVD-synthesized intrinsic and B-doped SCD. Density functional theory (DFT) calculations were employed to analyze the adsorption processes of hydrogen, carbonbased groups, B atoms, and acetone molecules on the surfaces of undoped and B-doped diamond supercells. The results demonstrate that B atoms replace carbon atoms in the diamond lattice, stabilizing the adsorption of hydrocarbon species and promoting diamond growth without significantly altering the lattice structure. Additionally, B-doped SCDs were synthesized using acetone and trimethyl borate as liquid carbon precursors under HFCVD environment. Increasing B doping concentration enhanced the epitaxial growth rate but also increased surface roughness and induced spherical protrusions. Excessive doping led to lattice distortion and tensile stress. These findings provide valuable insights into optimizing B-doped SCD growth processes for electronic and optoelectronic applications.