Determination of diamond growth rate in a flow tube geometry as a function of measured atomic hydrogen density

Present diamond deposition reactors have been very successful in furthering our understanding of how diamond grows at low pressures. However, their primary disadvantage is that changes in reactor conditions (e.g., filament temperature or microwave power, substrate temperature, and CH4:H2 concentration ratio in methane‐based reactors) change all chemical species and their relationships. Changes in diamond growth created by independent changes to a single species are not directly accessible. For example, it is known that making atomic hydrogen is required for the growth of diamond films. However, changes to film growth rate have not been tied quantitatively to changes in the amount of atomic hydrogen available. A high‐yield atomic hydrogen source was fabricated and pretested in a diamond growth setup. A previously developed atomic hydrogen sensor was used to measure atomic hydrogen density output as a function of both power and pressure. Diamond was then grown as a function of atomic hydrogen density, and g...