The role of nickel substrate thickness in determining the thickness of CVD-grown boron nitride films

Abstract In this paper, we report on the growth of sp ² -BN films by chemical vapor deposition on nickel (111). More precisely, we propose to explore a new parameter variation, which to our knowledge has never been studied in the literature, namely the thickness of the nickel substrate. The structure, the quality and the homogeneity of the resulting BN film are characterized from the atomic to the millimeter scale with a set of spectroscopic and imaging techniques. We show that by reducing the nickel thickness without changing all the other growth parameters, BN films pass from a thickness of 4–6 layers (1.2–1.6 nm) to 2–3 layers (0.6–0.9 nm). We discuss this result in relation to the literature on the growth mechanism. We propose that the growth occurs essentially during the cooling phase by precipitation on the Ni(111) substrate involving a bulk diffusion-segregation process of boron and nitrogen.