Growth of Hexagonal Boron Nitride Films on Silicon Substrates by Low-Pressure Chemical Vapor Deposition

By respectively using Boron trichloride and ammonia as the boron source and the nitrogen source, and nitrogen as the carrier gas, hexagonal boron nitride films were grown on (100) silicon substrates via a low-pressure chemical vapor deposition method in a deposition temperature range of 900–1300 °C with a total pressure of 100 Pa. The effect of temperature on crystalline quality of the hexagonal boron nitride films was investigated using X-ray diffraction and Raman spectra. It was demonstrated that stoichiometric polycrystalline hexagonal boron nitride films were synthesized at 1200 °C. A deep-ultraviolet photodetector based on a 2.3 µm hBN film exhibited a photo-to-dark-current ratio of ~ 312 at 20 V bias under the irradiation of a UV-enhanced xenon lamp. It indicates that hBN films are promising functional materials for high-performance solar-blind photodetectors.