High-Vacuum Chemical Vapor Deposition of Monolayer Hexagonal Boron Nitride on Ge(001) from Borazine

Hexagonal boron nitride (h-BN) is a promising material for next-generation electronics due to its unique optoelectronic and electronic properties. While the synthesis of h-BN on metallic substrates has been studied extensively, h-BN synthesis on CMOS-compatible substrates like Ge has not. Here, we report the growth of h-BN on Ge(001) from borazine via high-vacuum chemical vapor deposition. We find that the sublimation of Ge under high vacuum inhibits h-BN growth. To overcome this challenge, we place two Ge substrates face-to-face and achieve the growth of aligned h-BN islands and monolayer h-BN films.