Incorporation of nitrogen into polycrystalline diamond surfaces by RF plasma nitridation process at different temperatures: Bonding configuration and thermal stabilty studies by in situ XPS and HREELS

Abstract

In situ studies of low energy nitrogen species incorporated into diamond films are significant as they could lead to a better understanding of bonding configuration and defects formation of the modified surface. In this report, we investigate the interaction of radio frequency (RF) nitrogen plasma onto a polycrystalline diamond surface at different temperatures (RT, 250, 500, and 750 8C). The influence of RF nitridation temperature on the bonding configuration, thermal stability, and concentrations of incorporated species were systematically investigated by in situ X-ray photoelectron spectroscopy and high resolution electron energy loss spectroscopy (HREELS). Our results showed that local bonding configurations were influenced by the temperature of the RF nitridation process. The amount of nitrogen incorporated into the diamond surface decreased as the nitridation process temperature increases. RF nitridation performed at 750 8C showed the absence of reorganization in the local bonding configurations upon annealing to 1000 8C and their thermal stability was also found to be better. HREELS results displayed partial retrieval of the characteristic optical phonon overtone of diamond, after annealing to 500 8C, which indicates that the RF nitridation process was successful in incorporating nitrogen into diamond surface without inducing a graphitic near surface region.

Atomistic Insight into Nitrogen-Terminated Diamond(001) Surfaces by the Adsorption of N, NH, and NH2: A Density Functional Theory Study

“…For each case, we identify the favored adsorption geometry by total energy calculations and evaluate the nature of surface bonding by analyzing the density of states (DOS) and the corresponding charge distribution. Further calculations of the vibration of the adsorbed nitrogen species and the 1s core-level shift of surface carbons are complementary to the recent works that used HREELS and XPS, − calling for re-interpretation of some spectrum features in the literature. − Lastly, we present simulated images of adsorbed nitrogen species on diamond(001), in preparation for future work using scanning tunneling microscopy (STM). Our results highlight the flexibility of the nitridation of diamond surfaces, offering opportunities of controlling both the number and charge state of the shallow NV centers in the layer-by-layer construction of diamond-based devices.…”

“…Despite the valuable insight gained from the prior works, − there remains some ambiguity around the nitridated diamond surfaces, such as the composite, structure, and chemical state of the adsorbed nitrogen species. Here, we present DFT studies on the adsorption of representative nitrogen species (N, NH, and NH 2 ) on bare and hydrogenated diamond(001) surfaces, aiming to shed light on the atomistic description of the nitridated diamond surfaces.…”

Nitrogen-Terminated Diamond (111) Surface for Room-Temperature Quantum Sensing and Simulation

“…It has been recently demonstrated that high-quality N-terminated diamond (100) surface can be realized by using an indirect radio frequency N 2 plasma process that keeps the surface damages minimal caused by the plasma treatment. ,− Those samples were grown at temperature of ∼700 K with a pressure of nitrogen source at 170 Torr. The predominant component is substitutional nitrogen or mixed N/CH species at the surface, depending on the type of diamond substrate where the fraction of nitrogen termination reaches at least 0.5 ML.…”

Removal of Pharmaceutical Residues from Water and Wastewater Using Dielectric Barrier Discharge Methods—A Review

“…This was further complemented by Fabry et al [ 130 ] who reported that thermal plasma induced by DC or AC plasma torches is an adequate method for the conversion of waste to energy and can certainly be used for the remediation of numerous wastes including municipal solid wastes, heavy oil, used car tires and medical wastes by gasification processes. On the other hand, Chandran et al [ 131 ] investigated the efficiency of radio frequency (RF) plasma on nitridation that involved the incorporation of nitrogen onto the surface of the polycrystalline diamond at varied temperatures (250, 500, 750, 1000 °C). The results of their research showed that nitrogen content in the diamond surface declined with an increase in temperature during the nitridation process.…”