Single-Crystal Diamond Needle Fabrication Using Hot-Filament Chemical Vapor Deposition

Abstract

Single-crystal diamonds in the form of micrometer-scale pyramids were produced using a combination of hot-filament (HF) chemical vapor deposition (CVD) and thermal oxidation processes. The diamond pyramids were compared here with similar ones that were manufactured using plasma-enhanced (PE) CVD. The similarities revealed in the morphology, Raman, and photoluminescent characteristics of the needles obtained using the hot-filament and plasma-enhanced CVD are discussed in connection with the diamond film growth mechanism. This work demonstrated that the HF CVD method has convincing potential for the fabrication of single-crystal diamond needles in the form of regularly shaped pyramids on a large surface area, even on non-conducting substrates. The experimental results demonstrated the ability for the mass production of the single-crystal needle-like diamonds, which is important for their practical application.

A Modified Plasma Immersed Solid-Phase Impurity Assisted Doping Geometry for the Creation of Highly Fluorescent Cvd Nanodiamond

“…The role of activated hydrogen is also crucial during the diamond doping process, especially when the impurity source is a solid which is etched by the plasma. Particularly for the silicon, used in our experiments, the etching of the surface by energetic hydrogen atoms may led to the formation of volatile silicon-based species, most probably SiH 4 or SiH x radicals, that are involved in the incorporation of Si atoms during the nanodiamond growth and later in the SiV center formation [18]. To achieve a high SiV center concentration and homogenous distribution over the sample, as well as to eliminate the formation of individual silicon crystals on the substrate, the applied doping geometry has significant importance, as it is demonstrated below.…”

Gemological Characteristic Difference between Colorless CVD Synthetic Diamonds and Natural Diamonds

“…Experimental results show that these samples are relatively pure and have fewer impurities. CVD-7 and CVD-8 samples have a slight peak of luminescence peak near 1420 cm −1 , which is caused by the zero-phonon line of the 575 nm center (NV 0 ) [ 26 ]. This is the reason why CVD-7 and CVD-8 samples have low color grades.…”

CVD Diamond Growth Enhanced by a Dynamic Magnetic Field

“…Equation (2) shows that the defect fraction in diamond films is proportional to the growth rate G and is also related to the reciprocal of the square of the atomic hydrogen concentration [H]. Since Goodwin's mode mainly accounted for sp 2 carbon-related defects, it can be used to specifically discuss diamond quality, as characterized by I D /(I D + I G /50) in our study.…”

“…A series of reactions in the gas phase as well as on the surface leads to the growth of a diamond phase, generally with a small admixture of the amorphous carbon phase. Due to its simplicity, HFCVD is the most commonly used method for the synthesis of diamond films [2,3].…”