Diamond growth on faceted sapphire and the charged cluster model

Chemical vapor deposition of diamond on an adamantane-coated sapphire substrate

“…7 Several studies for diamond growth used hot-lament chemical vapor deposition method with scratching pretreatment on sapphire to increase the nucleation density. [8][9][10] Also, there are a few studies of the growth of diamond on sapphire coated with a buffer layer of platinum and iridium. [11][12][13] However, the growth of diamond lms on optically transparent substrates like sapphire has to address several issues.…”

Tof-Sims Fragment Pattern Analysis Of Boron-Doped Chemical Vapour Deposition Diamond

“…Figure 4 also shows the presence of CH -, C2H -, C2H3at m/z = 13, 25 and 27, respectively. While it is possible that CxHyfragments may have originated from the CVD diamond due to a copious amount of hydrogen in the CVD environment during the fabrication process (Saw et al, 2003;Saw & du Plessis, 2005), we attribute them to adventitious hydrocarbons on the sample surface. The SO3peak at m/z = 79.9570 as well as the Cl -, CN -, CNOand several CxHyOz fragments are attributed to atmospheric aerosol particles on the sample surface (Zhang et al, 2016;Zhu, Olson, & Beebe, 2001).…”

Effect of diffusion length on the nucleation of chemical vapour deposition diamond

“…After 15 min of deposition, isolated diamond particles could be observed on the faceted sapphire surface [3]. An early onset of diamond formation suggests that there is no intermediate layer between the diamond particles and the underlying sapphire substrate.…”

“…While the hydrocarbon species that are not adsorbed may leave the substrate surface by desorption into the gas phase again, the adsorbed species decompose into carbon atoms before diffusing along the substrate surface or into substrate, forming an intermediate layer. In the case of diamond deposition on sapphire substrate, there is no formation of an intermediate layer [3,8,9]. Due to the absence of an intermediate layer, no incubation period is observed and diamond nucleation occurs directly on the sapphire surface as a result of the surface diffusion of the adsorbed carbon atoms.…”

“…This article demonstrates that no nucleation enhancement will occur for the case where k is smaller than or comparable with the width of the terraces. Some of the results of our recent diamond growth experiments on the faceted sapphire substrate had been reported [3][4] before but the effect of the diffusion length of the nucleation precursors on diamond nucleation in these experiments had not been studied. For the sake of clarity, these experiments as well the previously unreported results of diamond growth on the mirror-polished as-received single crystal a-(0 0 0 1) sapphire substrates are described in this article.…”