Deposition of Boron Nitride Films by Filament-Assisted CVD Using Tris (Bimethylamino) Borane Precursor

摘要

Boron nitride films were deposited on silicon substrate by a hot filament assisted chemical vapor deposition (HFCVD) system. The tris(dimethylamino)borane(B[N(CH_3)_2]_3) was used as the single source precursor which has both the boron and nitrogen source, ammonia gas was used as the assisted gas to increase the nitrogen concentration in the films. The films deposited by different ratios of precursor to ammonia gas flow rate and filament temperatures were investigated. The boron-carbon-nitrogen (BCN) compound films were deposited under lower filament temperature. With increasing the ammonia gas flow rate, the carbon concentration in the films decreased. Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM) image reveal that hexagonal boron nitride (hBN) films were deposited at the higher filament temperature of 2000°C. Moreover, the crystallization degree of the films became better with the filament temperature increased.