Effect of Flow Rate and Precursor Sublimation Temperature on the LPCVD Growth of Hexagonal Boron Nitride

Abstract

Hexagonal boron nitride (h-BN) is known as promising 2D material with a wide band-gap $( 5.2 \sim 5.9$ eV) which has high breakdown strength. To synthesize h-BN films, chemical vapor deposition (CVD) method is proved to be an effective method that allows the scaled synthesis of h-BN. In this study, we demonstrate a low pressure chemical vapor deposition (LPCVD) method to synthesize complete and uniform h-BN films. In order to obtain high crystalline h-BN films, we studied the flow rate of carrier gas and precursor sublimation temperature on the growth of h-BN films. The results indicate the flow rate of carrier gas has little influence on growth of h-BN films. Nevertheless, the lower precursor sublimation temperature contributes to lower growth rate, which makes the thickness of h-BN films is easily controlled. When the sublimation temperature is more than 100 the thickness of h-BN films is hard to control. The breakdown strength of h-BN films is higher than 9.0 MV/cm from the I-V test, which makes h-BN films ideal substrates and insulators for 2D microelectronic devices.