Growth mechanisms of hexagonal boron nitride film by chemical vapor deposition

Among single layered two dimensional (2D) materials such as graphene, hexagonal boron nitride (hBN) and transition metal dichalcogenides (TMdCs), hBN is a unique insulator with an energy band gap of about 6 eV, owing to the strong ionic bonding nature between boron and nitrogen atoms. Due to the high chemical and thermal stabilities, as well as atomically smooth surfaces free of dangling bonds, hBN has been used as a barrier for passivation and as support layers in 2D electronic devices, to maximize the electrical and optical characteristics of 2D materials. However, there still remains a challenge to obtain large-area and high-quality hBN film for real 2D electronic devices. Chemical vapor deposition (CVD) is one of the promising methods to overcome the current limitations. In this chapter, we focus on the various CVD approaches such as thermal and plasma-enhanced CVD, and the growth mechanism of hBN in the CVD processes that includes: surface-mediation, precipitation, solid-phase epitaxy, and epitaxial growth. Lastly, we describe the present and future electronic device applications with hBN film.