Tailoring of nitrogen-vacancy colour centers in diamond epilayers by in situ sulfur and nitrogen anion engineering

Abstract

In this work, a sulfur and nitrogen co-doping technique has been demonstrated for diamond epilayer growth by microwave plasma chemical vapor deposition (MPCVD). Results show that the nitrogen concentration in films could be tailored by co-doping of sulfur. At a certain growth condition, single nitrogen-vacancy (NV) colour centers could be achieved. A competition mechanism between sulfur and nitrogen incorporation in the H 2 /CH 4 plasma is proposed to explain the efficient suppression of the incorporated nitrogen. Briefly, adding H 2 S decreases the growth rate and the resulting (S or S 2 ) species could react with the dissociated nitrogen atoms to form S and N-containing clusters. Hence, the concentration of the NV centers in diamond is decreased. Meanwhile, density functional theory (DFT) calculations indicate an increment of the NV formation energy in the presence of sulfur, which confirms that sulfur has a suppression effect on the formation of the NV centers. This study provides a new method to adjust the concentration of the NV centers in the diamond films.

Effect of oxygen on regulation of properties of moderately boron-doped diamond films

“…Vacancies would become mobile under high temperature (above 700 • C). [22] Then some of va- Since the oxygen in diamond is a donor-like defect and the boron and oxygen may form complex to affect the electrical properties, we have thus employed Hall-effect measurement to characterize the samples. Figure 5(a) shows the results of the hole concentration and the Hall mobility.…”

Suppression and compensation effect of oxygen on the behavior of heavily boron-doped diamond films

“…[14,15] In recent years, co-doping technology has been frequently employed in the area of wide-bandgap semiconductor material growth, especially in diamond. [16][17][18] Co-doping is a promising strategy that can be used to effectively tune the dopant populations, electronic properties and magnetic properties, resulting in an increase in dopant solubility, an increase in the activation rate by lowering the ionization energy of acceptors and donors and an increase in the carrier mobility. [16] For example, the effect of co-doping of sulfur and boron on the crystal quality of diamond and their incorporation efficiency were studied by Liu et al [17] They observed that sulfur incorporation led to evolution of the boron doping efficiency, hole mobility and concentration, crystal quality, surface morphology and growth rate.…”